NRDC Consent Decree - 2nd Annual Report
Note: This information is provided for reference purposes only. Although the information provided here was accurate and current when first created, it is now outdated.
September 26, 2003: EPA Actions Implementing Regulatory Determinations Required under Certain Provisions of the NRDC Consent Decree
In September 2001, the Federal Court for the Northern District of California entered a Consent Decree to conclude litigation in the case, Natural Resources Defense Council v. Whitman. Under the Consent Decree, EPA is required to issue an annual report providing information on the steps that the Agency has taken to implement certain regulatory determinations that it is required to make by the Consent Decree. Specifically, the Consent Decree directs EPA, beginning one year after the entry of the Consent Decree and annually for several years thereafter, to issue a report addressing the risks identified in certain previously issued Reregistration Eligibility Decisions (REDs) and Interim Reregistration Eligibility Decisions (IREDs). With respect to each covered RED and IRED, EPA is to identify any risks from pesticide use and/or any pesticide tolerances that the Agency has determined do not meet applicable statutory standards and to describe its plans for addressing the risk or tolerance. For REDs and IREDs discussed in the first annual report, EPA must describe its steps toward completing its plan to address identified risks or tolerances.
In addition, with respect to certain groups of pesticides which EPA has determined share a common mechanism of toxicity, the Consent Decree requires the first annual report on the group to contain a schedule for issuing a preliminary cumulative risk assessment and a revised cumulative risk assessment for the group. The second and subsequent annual reports for the group must describe EPA's steps toward completion of its schedules for completing these preliminary and revised cumulative risk assessments. The Consent Decree also requires EPA to post each annual report on its website. None of the schedules or plans contained in these annual reports are judicially enforceable.
Under the terms of the Consent Decree, the second annual report must describe risks or tolerances of concern and EPA's plan for addressing those risks or tolerances for the following individual active ingredients, for which EPA has issued a RED or IRED at least three months prior to the annual reporting date of September 26:
The second annual report also must describe EPA's steps toward completing its plan, discussed in the first annual report, for addressing unreasonable risks associated with:
The second annual report must include a schedule for completing preliminary and revised cumulative risk assessments for the triazines, for which EPA has determined that specific pesticides in the group share a common mechanism of toxicity. The second annual report also must provide updates on EPA's steps toward completion of its schedules for completing preliminary and revised cumulative risk assessments for the thiocarbamate and dithiocarbamate pesticides, common mechanism groups discussed in the first annual report.
Implementing REDs and IREDs
A number of steps must take place in order to translate risk mitigation determinations contained in RED or IRED documents into label language on pesticide products in the marketplace. Typically, EPA signs a RED or IRED document and then sends it, along with its attachments and appendices, to affected registrants for follow-up actions. Unless all products containing the pesticide active ingredient are being voluntarily canceled, a product-specific Data Call-In (DCI) is sent to the affected end-use product registrants along with the RED or IRED so that EPA can obtain product chemistry, acute toxicity, and other data that are required for product reregistration. If the RED or IRED includes additional confirmatory data requirements, EPA also issues a generic DCI to the affected technical or manufacturing use product registrants. At present, EPA must obtain Office of Management and Budget (OMB) approval under the Paperwork Reduction Act to issue these DCIs. Typically, EPA transmits the DCI to registrants of the pesticide along with the RED or IRED. The RED or IRED contains instructions to the registrants about when and how to submit applications for amended registration reflecting the risk mitigation measures contained in the RED or IRED. Following receipt of the applications, EPA reviews and, if appropriate, approves the amendments by sending a stamped copy of the new labeling to the registrant. Either the approval of the amendment or the RED or IRED will establish a time frame for the registrant to implement the new labeling.
Under FIFRA, Congress envisioned a process that could take up to 14 months for EPA to review applications to amend product labeling to implement the risk mitigation measures determined in a RED or IRED. Congress left EPA discretion about how quickly to require registrants to begin placing the new labeling on products entering the marketplace. EPA has often allowed companies more than a year to use up existing stocks of old product labels. Because of its concerns about the pesticides discussed below, EPA has departed from its typical practice in order to speed up the process of implementing the risk mitigation measures for azinphos-methyl, chlorpyrifos, phosmet, and propargite, as well as for atrazine, benomyl, carbaryl, diazinon, endosulfan, and lindane. Using Memoranda of Agreement, shorter deadlines for submission of applications, and other changes to our typical procedures, EPA believes that it will achieve implementation of the risk mitigation measures for these pesticides as soon as or sooner than the statute would otherwise envision.
Implementing REDs and IREDs
A number of steps must take place in order to translate risk mitigation determinations contained in RED or IRED documents into label language on pesticide products in the marketplace. Typically, EPA signs a RED or IRED document and then sends it, along with its attachments and appendices, to affected registrants for follow-up actions. Unless all products containing the pesticide active ingredient are being voluntarily canceled, a product-specific Data Call-In (DCI) is sent to the affected end-use product registrants along with the RED or IRED so that EPA can obtain product chemistry, acute toxicity, and other data that are required for product reregistration. If the RED or IRED includes additional confirmatory data requirements, EPA also issues a generic DCI to the affected technical or manufacturing use product registrants. Typically, EPA transmits the DCI to registrants of the pesticide along with the RED or IRED. The RED or IRED contains instructions to the registrants about when and how to submit applications for amended registration reflecting the risk mitigation measures contained in the RED or IRED. Following receipt of the applications, EPA reviews and, if appropriate, approves the amendments by sending a stamped copy of the new labeling to the registrant. Either the approval of the amendment or the RED or IRED will establish a time frame for the registrant to implement the new labeling.
Because of its concerns about the pesticides discussed below, EPA has expedited the process of implementing the risk mitigation measures for several of them. Using Memoranda of Agreement, shorter deadlines for submission of applications, and other changes to our typical procedures, EPA is achieving implementation of the risk mitigation measures for these pesticides more quickly than usual.
RED and IRED documents for the pesticides discussed in this second annual report are available from the pesticide reregistration status Web page . Many related support documents also are available from Regulations.gov.
I. REDs and IREDs
A. IRED Covered for the First Time
- Atrazine registrants must conduct weekly monitoring beginning in 2003 during the peak atrazine use season and biweekly monitoring during the rest of the year.
- If Total Chlorotriazine atrazine and degradates (TCT) levels are 37.5 ppb or greater as a 90-day rolling average at the CWS raw water intake after December 31, 2003, any use of atrazine in the watershed area will be prohibited.
- Registrants had to submit (and submitted) written Mitigation Plans by August 1, 2003, including mitigation measures (considering Best Management Practices such as buffer strips, grass waterways, changes in tillage practices, changes in application timing, and use rate reductions, and how to communicate the measures to growers), to be implemented within the watershed areas containing each CWS.
- Registrants will submit quarterly progress reports describing measures taken during that quarter.
- Atrazine registrants must conduct weekly monitoring during the peak atrazine use season and biweekly monitoring during the rest of the year, beginning in 2004 at the latest.
- After December 31, 2003, if TCT levels are found in two separate years within a 5-year period to be at or above 37.5 ppb as a 90-day rolling average at the CWS raw water intake, any use of atrazine within the watershed area will be prohibited.
- After the first exceedence of the 37.5 ppb limit, atrazine registrants must submit and begin implementing within 90 days a written Mitigation Plan including mitigation measures to be implemented within the watershed (considering Best Management Practices such as buffer strips, grass waterways, changes in tillage practices, changes in application timing, and use rate reductions, and how to communicate the measures included in the plan with growers).
- Atrazine registrants will submit quarterly progress reports describing measures taken during that quarter.
- Within 90 days of the original signature date of the MOA (January 31, 2003), atrazine registrants were required to establish an Atrazine Watershed Information Center (AWIC) to provide up-to-date, detailed information on what watershed areas have become subject to a prohibition on atrazine use. This information is available to the public 24 hours a day, 7 days a week, through a toll-free telephone number and an Internet web site.
- Atrazine registrants will define a protocol for monitoring TCT levels in rural wells, and EPA will review the protocol within a reasonable period.
- Atrazine registrants will develop a program to monitor for atrazine concentrations and mitigate environmental exposures if EPA decides mitigation is necessary to avoid unreasonable adverse effects on the environment. This program will focus on watershed impacts of atrazine use, and will be implemented on a tiered watershed level, consistent with existing state and federal water quality programs.
- Further information on repurchasing, relabeling, and other aspects is captured in the Atrazine MOA.
- Measures in the MOA address dietary risk, as driven by drinking water concentrations:
- A performance standard must be met in these CWS's, and use of atrazine must be prohibited in the watershed if the performance standard is not met
- Extensive monitoring data must be gathered in these CWS's and others in atrazine use areas
- To confirm that risks from atrazine in rural wells is not a concern, monitoring data for atrazine levels in rural wells in atrazine use areas also must be collected
- The provisions of the MOA will be implemented in part through a new statement required on most atrazine product labels under the Directions For Use: "ANY USE OF THIS PRODUCT IN AN AREA WHERE USE IS PROHIBITED IS A VIOLATION OF FEDERAL LAW." Potential users must consult the Atrazine Watershed Information Center (AWIC) to determine whether atrazine is prohibited in their watershed. If use of atrazine is prohibited, owners may return atrazine products to their point of purchase for a refund.
- For products containing 4% or less atrazine active ingredient, removal of the product from shelves in prohibited areas is a condition of registration.
- Prohibit applications of granular lawn products by hand
- Restrict applications of granular lawn products using hand-held devices to spot applications only
- Reduce maximum 1-time application rate for liquid formulations on lawns and turf to 1 pound active ingredient per acre (lb ai/A) from 2 lb ai/A
- Require that granular lawn products be watered in
- Require closed mixing and loading systems for the following scenarios:
- mixing and loading liquid formulations for aerial application at a rate greater than 3 lb ai/A
- mixing and loading dry flowable formulations for aerial application
- Require PPE (coveralls over long-sleeved shirt and long pants, chemical-resistant
footwear plus socks, chemical resistant gloves, NIOSH approved
dust/mist respirator with the appropriate filter, chemical resistant headgear
for overhead exposure, and a chemical resistant apron if exposed to the undiluted
product) for the following:
- mixers, loaders, applicators and other handlers of liquids and wettable powders (not using Engineering Controls), and
- handlers of dry flowables (not packaged in water soluble packaging).
- Require that all wettable powder products be packaged in water soluble bags.
- Require closed cockpits (40 CFR 170.240(d)(4)) for aerial applications
- Require closed cabs (40CFR 170.240(d)(5)) for flaggers.
- Restrict the impregnation of bulk fertilizer to commercial facilities (prohibit on-farm impregnation)
- Restrict the impregnation of dry bulk fertilizer to 500 tons per day for no more than 30 days per calender year per facility
- Reduce the maximum application rate for handlers applying liquids with rights-of-way sprayers to 1.0 lb ai/A
- Require a 60-day pre-harvest interval (PHI) for field corn forage uses
- Require a 45-day PHI for sweet corn forage uses
- Require a 60-day PHI for preemergent uses and a 45-day PHI for postemergent sorghum forage uses
- Require that all wettable powder products be packaged in water soluble bags.
- Require the use of long-sleeved shirt and long pants, shoes and socks
for loaders, applicators and other handlers using the following formulation:
- Require the use of long-sleeved shirt and long pants, shoes and socks,
and chemical resistant gloves for mixers, loaders, applicators and other
handlers using the following formulations:
- water dispersable granules
- wettable powders
- dry flowables
- Require the use of coveralls over long-sleeved shirt and long pants,
chemical resistant gloves, chemical resistant footwear plus socks, a NIOSH approved dust/mist
respirator and an apron if exposed to the concentrate for the following
- Liquids: (1) mixers and loaders of liquids supporting groundboom or hand-gun applications and applicators applying liquids by backpack sprayers or low- pressure handwand equipment; (2) all other handlers of liquid products must wear long-sleeved shirt and long pants, and shoes and socks.
- Reduce the maximum single application rate for liquid formulations on residential lawns and turf to 1 lb ai/A from 2 lb ai/A (liquid products containing >4% ai are restricted use)
- Require that granular lawn products be watered in
- Restrict the application of granular lawn products when using hand-held devices (e.g. belly grinder) to spot applications only.
- Prohibit applications of granular lawn products by hand
- Reduce the maximum single application rate for liquid formulations on residential lawns and turf to 1 lb ai/A from 2 lb ai/A (liquid products containing >4% ai are restricted use)
- Require that granular lawn products be watered in
- The generic and product-specific DCIs for atrazine, requesting the monitoring data described above and some ecological effects data, residue chemistry data, and a new toxicity study, have been approved by OMB and will be issued shortly.
- The MOA was signed by Syngenta; now EPA is working with the other atrazine technical registrants to provide additional information and obtain signatures.
- Letters requesting label amendments and the IRED and DCIs will be sent to atrazine registrants after MOA signatures are obtained.
- Drinking water monitoring has begun.
- EPA (OPP, ORD, and OW) is working with Syngenta on the ecological program.
- Scientific experts have completed and submitted a report to EPA regarding potential developmental effects of atrazine on amphibians. The SAP met in June 2003 to review EPA's evaluation of 17 laboratory and field studies concerning potential developmental effects on amphibians. The panel also was asked to comment on EPA's conceptual model for future studies to evaluate the potential effects of atrazine on frogs and other amphibians. The SAP concluded that EPA's review was thorough, the approaches and criteria were appropriate, and the Agency's conclusions were valid, given the data reviewed. The SAP agreed that additional studies are warranted to reduce scientific uncertainty regarding whether atrazine causes replicable effects on amphibians. EPA will consider the SAP's comments in developing the revised Atrazine IRED, which is to be completed by October 31, 2003.
- The SAP convened in July 2003 to advise EPA on the epidemiological data relating to prostate cancer and exposure to atrazine, and provided their report to the Agency on this issue recently. EPA will consider the SAP's comments in completing the revised Atrazine IRED.
- Cancellation of all granular registrations, except lettuce and two current Section 24(c) registrations held by Washington and Oregon for control of the cranberry girdler.
- Deletion of aerial application for all uses.
- Deletion of foliar application on all vegetable crops, except for treatment of leafhopper on honeydew melons in California.
- Application rate reduction for ornamentals and lettuce.
- Establishment of crop specific restricted entry intervals (REIs). REIs of 2 days to 18 days will be established for all crops.
- Cancellation of all seed treatment uses.
- Require engineering controls for all uses. All application equipment must use lock and load engineering controls. All wettable powder formulations must be packaged in water soluble bags. Closed cabs are required for all ground equipment.
- Reduce the number of applications of diazinon per growing season. For most uses, only one application per growing season will be allowed. Crops with dormant season and in season uses (e.g., stone fruits) will have one application per season, for a total of two applications per year. Other exceptions are noted in the Labeling Summary Table in Chapter 5 of the IRED.
- Cancellation of the following uses:
- Section 3 registrations: Chinese broccoli, Chinese cabbage, Chinese mustard, Chinese radish, corn, grapes, hops, mushrooms, sugarbeets, walnuts, and watercress.
- Section 24(c) registrations: Control of cranberry girdler for grass grown for seed (Oregon); dipping of pineapple seed pieces (Hawaii); drenching around residential fruit trees for control of Mediterranean fruit fly (California).
- The Diazinon IRED was issued with a 60-day public comment period through a Federal Register notice published on September 25, 2002. This comment period was extended in December 2002 for an additional 30 days, closing January 8, 2003. EPA is reviewing the public comments received and will amend the Diazinon IRED if appropriate. A Response to Comments document will be placed in the Agency's EDOCKET.
- The generic and product-specific DCIs for diazinon have been approved by OMB and will be issued soon.
- EPA plans to meet with the registrant in the near future, once the DCIs have been issued, to finalize the needed labeling changes.
- To resolve worker risk issues within 19 months of the Diazinon IRED signature date (or by the end of February 2004), as required by the Consent Decree, EPA will discuss relevant labeling changes in the meeting with the registrant, described above.
- Delete use on succulent beans, succulent peas, spinach, and grapes
- Delete use on pecans;
- Reduce maximum seasonal application rates from 3 pounds active ingredient per acre (lbs./ai/A) to 2.5 lbs./ai/A for pome fruit, stone fruit, and citrus;
- Reduce maximum seasonal application rate from 3 lbs./ai/A to 2 lbs./ai/A for melons, cucurbits, lettuce, tomatoes, sweet potatoes, cotton (ground), broccoli, cauliflower, cabbage, kohlrabi, brussels sprouts, strawberries, filberts, walnuts, almonds, macadamia nuts, peppers, eggplant, potatoes, carrots, dry beans, dry peas, and tobacco;
- Reduce maximum seasonal application rate from 3 lbs./ai/A to 1.5 lbs./ai/A for sweet corn, cotton (aerial) and blueberries;
- Reduce maximum seasonal application rate from 3 lbs./ai/A to 1 lb./ai/A for celery;
- Require 100 foot spray buffer for ground applications between a treated area and water bodies;
- Require 30 foot maintained vegetative buffer strip between a treated area and water bodies;
- Require all products to be Restricted Use;
- Restrict use on cotton to AZ, CA, NM, OK and TX only; and
- Restrict use on tobacco to IN, KY, OH, PA, TN and WV only.
- Require all wettable powders to be packaged in water soluble bags;
- Cancel use of wettable powders on tomatoes, sweet corn, sweet potatoes, cotton, small grains, alfalfa (seed), carrots, dry beans, dry peas, pineapples, and tobacco;
- Cancel aerial application using the wettable powder formulation on pome fruits, stone fruits, citrus, blueberries, strawberries, collard greens (seed), kale (seed), mustard greens (seed), radish (seed), turnip (seed), rutabaga (seed), broccoli, (seed), cauliflower (seed), kohlrabi (seed), cabbage (seed), filberts, walnuts, almonds, and macadamia nuts;
- Require closed mixing/loading systems for aerial application using the EC formulation on pome fruits, stone fruits, citrus, sweet corn, sweet potatoes, cotton, collard greens (seed), kale (seed), mustard greens (seed), radish (seed), turnip (seed), rutabaga (seed), broccoli, (seed), cauliflower (seed), kohlrabi (seed), cabbage (seed), blueberries, small grains, alfalfa (seed), filberts, walnuts, almonds and macadamia nuts;
- Require closed cabs for airblast applications on pome fruits, stone fruits, citrus, filberts, walnuts, almonds and macadamia nuts;
- Prohibit use of high pressure handwands with rates greater than 0.005 lbs/ai/gal;
- Increase REI to 48 hours for all crops except as noted in the following bullets;
- Increase REI for WP products to 3 days for melons and cucurbits;
- Increase REI for WP products to 4 days for lettuce, celery, pome fruit, stone fruit, citrus, collard greens, kale, mustard greens, radish, turnip, rutabaga, ornamental trees and shrubs;
- Increase REI for WP products to 5 days for collard greens (seed), kale (seed), mustard greens (seed), radish (seed), turnip (seed) and rutabaga (seed);
- Increase REI for WP products to 9 days for blueberries, broccoli, cauliflower, kohlrabi, cabbage, and brussels sprouts;
- Increase REI for WP products to 12 days for broccoli (seed), cauliflower (seed), kohlrabi (seed), and cabbage (seed);
- Increase REI for EC products to 3 days for sweet potatoes
- Increase REI for EC products to 4 days for broccoli, cauliflower, kohlrabi, cabbage, and brussels sprouts;
- Increase REI for EC products to 6 days for blueberries;
- Increase REI for EC products to 7 days for broccoli (seed), kohlrabi (seed), and cabbage (seed); and
- Increase REI for EC products to 17 days for sweet corn.
- EPA published a Federal Register notice on November 6, 2002, announcing the availability of the Endosulfan RED and opening a 60-day public comment period that closed on January 6, 2003. A summary of the comments received is under development. Some amendments to the RED may be needed based on the comments received.
- The generic and product-specific DCIs for endosulfan have been approved by OMB, and the Agency plans to issue these DCIs in Fall 2003.
- EPA's Office of Pesticide Programs (OPP) will work with the Endosulfan Task Force, interested federal and state agencies, and other stakeholders to finalize and implement a targeted monitoring protocol to resolve the uncertainty related to endosulfan use near vulnerable aquatic areas that may pose a risk to non-target aquatic animals.
- Use on the 5 deleted crops (succulent beans, succulent peas, spinach, grapes, and pecans) will be eliminated over the next several years, consistent with EPA's existing stocks provisions.
- Prohibit on-farm treatment of wheat, barley, oats, and rye seeds with the lindane dust formulation;
- Reduce maximum application rate for corn to 0.0558 lb ai/100 lb seed;
- Workers must wear double layer clothing (coveralls over long-sleeved shirt and long pants, chemical-resistant footwear), chemical-resistant gloves, and a dust/mist respirator for on-farm treatment of corn and sorghum seeds only with the dust formulation;
- A 24-hour REI is necessary for all seed treatment uses;
- All lindane end-use product labels must specify a 30-day plantback interval for leafy vegetables and a 12-month plantback interval for all other unregistered crops. The registrant may conduct a confined accumulation of rotational crops study to show that these plantback intervals can be reduced.
- FDA issued a Public Health Advisory in March 2003, announcing significant updates to the labeling of lindane lice and scabies treatment products.
- Lindane labels now contain a "boxed" warning to highlight the most important safety issues, and provide information to both health care professionals and patients regarding the risks associated with the use and misuse of lindane.
- The warning emphasizes that lindane is a second-line therapy, to be used only if other lice/scabies medications are not tolerable or other approved therapies have failed.
- The warning also emphasizes that lindane products are to be used with caution in patients who weigh less than 110 pounds, that they are not recommended for use on infants, and that they are contraindicated for premature infants.
- Maximum product size and prescribed dose will be either 1 or 2 ounces.
- The instructions for use and information about adverse events will also be provided to patients in the form of a Medication Guide. By law, the Medication Guide must be dispensed by pharmacists directly to the patient with each new prescription of Lindane Lotion or Lindane Shampoo. A Medication Guide is provided with products that pose serious or significant public health concerns and is in addition to patient package inserts. It is mandatory, and is written in English in nontechnical, understandable language for the patient/consumer.
- Other labeling changes include increased warnings for immuno-compromised patients, or patients on medications such as antidepressants that may increase the risk of having a seizure.
- EPA requested public comments on the Lindane RED during a 60-day public comment period, as announced in a Federal Register notice published September 25, 2002. The Agency is developing responses to the comments received; however, none require changes to the RED.
- The generic and product-specific DCIs for lindane have been approved by OMB, and the Agency plans to issue these DCIs in October 2003.
- Through a previously issued DCI, EPA required a treated seed/grain crop metabolism study that could enable the Agency to establish new lindane tolerances. The registrant plans to begin the study in October 2003, and anticipates sending EPA the study report by the end of 2004.
On January 31, 2003, EPA released the Atrazine IRED and a Memorandum of Agreement with the principal atrazine registrant to implement an innovative and effective program to protect community drinking water systems from contamination by this widely used herbicide. The Agency believes that certain uses of atrazine cause unreasonable adverse effects on human health and the environment, and that such effects can be mitigated with the risk mitigation measures identified in the Atrazine IRED. EPA recommended that registrants implement those risk mitigation measures as soon as possible. Atrazine is eligible for reregistration provided that all the conditions in the IRED are satisfied, including implementation of the interim risk mitigation measures outlined in the document, and provided that the cumulative risk conclusions for the triazine pesticides support a final reregistration eligibility determination.
First registered in 1958, atrazine is estimated to be the most heavily used herbicide in the U.S. Approximately 76.4 million pounds are applied annually to control broadleaf and some grassy weeds. Corn accounts for about 86% of total U.S. domestic usage, followed by sorghum (10%) and sugarcane (3%). All other uses, including use on golf course turf and residential lawns, make up the remaining 1%. Approximately 75% of all field corn acreage grown in the U.S. is treated with atrazine, and most atrazine use is in the Midwest.
Atrazine is the most commonly detected pesticide in surface water. Atrazine's frequent detection in streams, rivers, groundwater, and reservoirs is related directly to both its volume of use and its tendency to persist and move with water.
The Atrazine IRED was developed through the pesticide public participation process, which increases transparency and maximizes stakeholder involvement in the Agency's development of risk assessments and risk management decisions. EPA's Office of Pesticide Programs and Office of Water worked extensively together and with stakeholders and affected parties to reach the decisions presented in the Atrazine IRED. During the past several years, the Agency has exchanged information on atrazine with the U.S. Department of Agriculture (USDA), U.S. Geological Survey (USGS), Fish and Wildlife Service (FWS), other federal and state agencies, registrants, users, the environmental community, water advocacy groups, concerned citizens, and others. Atrazine has been reviewed and recommendations have been provided several times by the independent Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) Scientific Advisory Panel (SAP). This significant input from stakeholders, the scientific community, and others helped inform EPA's reregistration eligibility decision on atrazine. While the IRED represents EPA's current evaluation of the human health and ecological risks of atrazine, its conclusions are subject to modification in light of new information.
EPA is continuing to evaluate atrazine's potential effects on amphibians' endocrinology and reproductive and developmental responses. The Agency submitted this issue to the SAP in June 2003, and has received a report from the SAP. In addition, in July 2003, EPA presented to the SAP its assessment of new information concerning atrazine and prostate cancer. The Agency also has received a report from that SAP meeting. See the July 17, 2003, Minute Meetings (Report). As required under an amendment to the Consent Decree, EPA currently plans to complete a revised Atrazine IRED by October 31, 2003.
Finally, EPA also must consider the cumulative effects of the triazine pesticides atrazine, simazine, and propazine, and their common chlorinated degradates, which share a common mechanism of toxicity. When the Agency completes its cumulative assessment of the triazine pesticides, final tolerance reassessment decisions for atrazine and the other triazines will be issued. At that time, EPA may need to pursue further risk mitigation for atrazine to address any risks identified in the triazine cumulative assessment.
Description of Unreasonable Adverse Effect Upon the Environment or Reason Tolerance Does Not Meet Section 408 Safety Standard.
In consultation with the SAP, EPA found that atrazine is not likely to be carcinogenic to humans; however, in July 2003, the Agency asked the SAP to reconsider this issue based on some newly received data. Atrazine has been associated with causing imbalances in hormonal levels in laboratory animals, possibly disrupting reproductive and developmental processes, and affecting ecosystem structure in the environment. Although atrazine does not pose risks through food, the Agency's drinking water, residential, occupational, and ecological risk assessments for atrazine indicate risks of concern. EPA considered human health effects and the exposure levels that created risk concerns in developing risk mitigation measures for atrazine.
EPA's Plan for Addressing Risks
To mitigate the identified risks, additional monitoring for atrazine levels and certain changes in atrazine use are necessary, as described fully in the Atrazine IRED. These changes will be implemented through atrazine product label amendments. To further address drinking water concerns and address some ecological risks, EPA and the technical registrants of atrazine developed a Memorandum of Agreement that sets forth additional requirements designed to reduce the most significant atrazine exposures. Among other requirements, the atrazine MOA includes a performance standard for community water systems, targeted monitoring of raw water entering certain community water systems in areas of atrazine use, and if atrazine is detected in water at levels above Agency safety standards, prohibition of use in that watershed area.
Risk Mitigation and the Atrazine Memorandum of Agreement
The Atrazine Memorandum of Agreement (MOA), signed by the primary atrazine technical registrant and EPA on January 31, 2003, will substantially mitigate atrazine risks by reducing the most significant exposures associated with agricultural and residential uses - exposures through drinking water. Under the MOA, the Agency is requiring an extensive drinking water monitoring program beginning in 2003 and the submission of regular/quarterly reports to EPA following an established schedule. Any failure to conduct this monitoring or submit these reports may result in cancellation of all atrazine registrations without a hearing.
Program for Highly Vulnerable Community Water Systems. In 8 Community Water Systems (CWS's) where atrazine residues already have been detected in drinking water at levels that exceed the Agency's level of concern:
Program for Other Vulnerable Community Water Systems. In about 120 other CWS's where SDWA data show annual average TCT levels of 2.6 ppb or greater:
Program for Other Areas. For all other watersheds where atrazine is used, the SDWA requires routine monitoring of finished drinking water for atrazine. If atrazine is detected at levels approaching the MCL, then additional monitoring and regulatory oversight will be triggered. If the MCL is violated, the registrant is required to take steps to assist the CWS to come into compliance with the MCL.
Other Provisions of the MOA
Risk Mitigation and the Atrazine IRED
To mitigate risks of concern and support provisions of the Atrazine MOA, the following measures are required by the Atrazine IRED.
Dietary Risk Mitigation. Acute risk estimates for food and drinking water and chronic food risk estimates do not exceed the Agency's level of concern. Intermediate-term (seasonal) drinking water risk estimates do exceed EPA's level of concern in 34 CWS's, primarily in the Midwest. The registrant has added three CWS's, for a total of 37 CWS's of concern.
Cancer Risk Mitigation. In accordance with the 1999 Interim Guidelines for Carcinogen Risk Assessment, EPA's Cancer Assessment Review Committee (CARC) classified atrazine as "not likely to be carcinogenic to humans." As summarized by the FIFRA Scientific Advisory Panel (SAP), "there are considerable differences between hypothalamic-pituitary-ovarian function in rats and humans, and the effects of aging on the function of the axis also is quite dissimilar. Therefore, it is unlikely that the mechanism by which atrazine induces mammary gland tumors in female SD rats could be operational in humans. Nevertheless, it is not unreasonable to expect that atrazine might cause adverse effects on hypothalamic-pituitary function in humans" (SAP, 2000). Although the cancer mode of action may not be operative in humans, the SAP went on further to state that the same endocrine perturbations that induce tumors also appear to play a role in at least some reproductive developmental effects (not associated with reproductive aging) which may be relevant to humans. The Agency also concluded that the cancer mode of action is not relevant to humans. Consequently, a quantitative cancer risk assessment was not conducted for atrazine. However, EPA agreed in the August 2002 amendment to the Consent Decree in NRDC v. Whitman to present to the SAP data concerning atrazine exposure and prostate or other cancers in humans that had been received by EPA after the May 2002 risk assessment but prior to February 28, 2003. In July 2003, EPA presented to the SAP its assessment of new epidemiological information concerning atrazine and prostate cancer. The Agency received a report from that SAP meeting in September 2003. The SAP comments will be addressed in the revised Atrazine IRED to be issued by October 31, 2003.
In its presentation to the SAP, EPA also noted that additional epidemiological studies and analyses are expected in the future, including: a report from the National Cancer Institute re-analyzing Hodgkin's lymphoma using hierarchical techniques to adjust for the effects of multiple exposures; an update of the Agricultural Health Study on prostate cancer capturing additional prostate cancer cases; an analysis of all the non-Hodgkin's lymphoma cases reported in the Agricultural Health Study; a special analysis of all cancers related to atrazine exposure in the same Agricultural Health Study cohort; and a nested case-control study conducted by Syngenta of workers at the St. Gabriel plant using more detailed job histories to evaluate exposure indices. Given the importance of incorporating these results into an evaluation of atrazine for prostate cancer and other cancer outcomes, the Agency plans future analyses of these reports. Absent compelling information in the interim, EPA will wait until all of these analyses are in before addressing the broader question of atrazine exposure and cancer.
Residential Risk Mitigation. Residential lawn and turf use of atrazine results in risks of concern to children reentering treated turf, and for homeowners applying atrazine to turf using a bellygrinder.
To mitigate these risks, the following measures are necessary:
Occupational Risk Mitigation. Occupational exposure to atrazine is of concern to the Agency. For agricultural and turf/lawn care operator uses of atrazine, several mixer/loader/applicator risk scenarios exceed the Agency's level of concern at baseline personal protective equipment (PPE) or label PPE. To mitigate these risks, the following measures are necessary.
Non-Agricultural Products (Lawns and Turf)
Ecological Risk Mitigation. Ecological risks are also of concern to EPA. The environmental risk assessment suggests that atrazine exposure could result in community-level and population-level effects in aquatic communities at concentrations of 10-20 ppb atrazine. To reduce these risks, an ecological assessment process to identify and monitor water bodies is needed. It may also be necessary to undertake mitigation in these vulnerable ecosystems. The specifics of this ecological program are being negotiated with the atrazine registrants. In addition, EPA will consider amphibian risk after obtaining further data on this issue.
Current Status of Implementation of Risk Mitigation Measures
EPA has completed its reregistration eligibility decision for the fungicide benomyl. Although benomyl was scheduled for a RED in 2002, the registrants requested voluntary cancellation in 2001 and 2002. After considering public comment, EPA granted the voluntary cancellation requests. At present, all benomyl product registrations have been canceled and all tolerances have been revoked. In completing its reregistration review of benomyl, in view of the substantive data gaps, absence of necessary tolerances, and absence of a registered source of benomyl manufacturing product, EPA found that benomyl does not meet the statutory requirements for reregistration.
Benomyl was first registered in 1969 by E.I. du Pont de Nemours and Company (DuPont). A systemic foliar fungicide, benomyl was used to control a wide range of diseases of fruits, nuts, vegetables, and field crops. Benomyl was registered for use on many agricultural crops. Over the years, DuPont canceled a number of agricultural uses of benomyl, as well as turf and residential uses.
The Benomyl RED and RED fact sheet are available from the pesticide reregistration status Web page.
Description of Unreasonable Adverse Effect Upon the Environment or Reason Tolerance Does Not Meet Section 408 Safety Standard.
A benzimidazole carbamate, benomyl rapidly degrades to carbendazim (MBC), also a registered pesticide active ingredient. Both benomyl and MBC are of toxicological concern. Effects associated with benomyl and MBC include liver toxicity, developmental toxicity (such as fetal eye and brain malformations and increased mortality), and reproductive (testicular) effects. Both benomyl and MBC also are considered possible human carcinogens.
In reviewing benomyl/MBC for reregistration, EPA found that substantive data gaps existed. Additional data from the major scientific disciplines was needed to complete risk assessments for benomyl/MBC and make a reregistration eligibility decision. Outstanding data requirements included toxicology (developmental neurotoxicity, 2-generation reproduction, subchronic, and dermal toxicity), product chemistry, residue chemistry, occupational exposure, and environmental fate and effects studies. For a complete list of data gaps, see the Benomyl RED.
EPA's Plan for Addressing Risks
On April 18, 2001, DuPont met with EPA and requested voluntary cancellation of all their registrations for products containing benomyl. EPA published a Federal Register notice on May 23, 2001, announcing receipt of DuPont's request for voluntary cancellation and inviting public comment during the next 30 days. The Agency considered the comments submitted and on August 8, 2001, published a cancellation order for DuPont's benomyl registrations, effective that day. Most other companies holding benomyl product registrations also requested voluntary cancellation of their registrations, as announced by EPA in an October 12, 2001, Federal Register notice. After considering public comment, EPA published a cancellation order for those products on January 15, 2002. A final benomyl end-use product registrant requested voluntary cancellation of their single benomyl product registration on July 31, 2002, as announced by EPA in the Federal Register on September 9, 2002. The company stated that they no longer manufactured or distributed their benomyl product and that there were no inventories of remaining stocks. EPA granted the requested voluntary cancellation of the last benomyl end use product registration after the end of the 30-day comment period, in October 2002.
One hundred benomyl tolerances existed for food and feed items such as fruits and nuts, vegetables, soybeans, grains, meat, milk, and eggs. EPA published a Federal Register notice on January 15, 2002, proposing to revoke tolerances for benomyl, and a follow-up notice on July 17, 2002, revoking all benomyl tolerances. The July 17, 2002 Federal Register notice describes the effective dates for tolerance revocation. Most dates are 3 to 6 years beyond December 31, 2002, the last date when people other than the registrant could sell and distribute existing stocks of benomyl products. These dates allow adequate time for commodities which may contain benomyl residues to clear the channels of trade.
At present, all benomyl product registrations are canceled and all tolerances are revoked, with expiration dates ranging from January 1, 2006, to January 1, 2009. EPA believes that use of any remaining benomyl products will end in 2003, given that production of benomyl ceased in 2001, and the sale and distribution of benomyl products ended on December 31, 2002. Any treated fresh commodity or processed food should have ample time during the next several years to clear trade channels.
MBC is currently registered as a fungicide/preservative in paints, coatings, plaster, and adhesives. No food uses are associated with MBC. Because MBC was initially registered after November 1, 1984, it is not subject to reregistration under FIFRA.
MBC is also the primary metabolite of thiophanate-methyl. EPA completed a RED for thiophanate-methyl in March 2003. The Agency had concerns with the aggregate short-term exposure to MBC and thiophanate-methyl resulting from food, water, and residential uses. These risks were mitigated by label use rate reductions.
EPA has assessed the risks of diazinon and on July 31, 2002, completed an Interim Reregistration Eligibility Decision (IRED) for this organophosphate (OP) pesticide. Without mitigation, diazinon poses unreasonable risks to agricultural workers and to birds and other wildlife species. To increase protection for workers, birds, and the environment, the Agency's decision includes provisions to phase out and cancel certain agricultural crop uses, the granular formulation, and aerial applications; reduce the amount and frequency of use; and employ engineering controls and other protective measures. These changes in diazinon use were developed through discussions with the technical registrants and were based on extensive stakeholder input.
Diazinon has been one of the most widely used insecticides in the U.S. for household as well as agricultural pest control. Under a December 2000 Memorandum of Agreement (MOA) with the technical registrants, all indoor and outdoor residential uses of diazinon are being canceled over a period of several years in order to reduce risks to children and others. Prior to residential mitigation, diazinon was used outdoors on household lawns and gardens to control insects, grubs, and nematodes in turf; indoors for fly control through crack and crevice treatments; and for veterinary use to control fleas and ticks through pet collars.
Diazinon is used in agriculture to control foliage and soil insects and pests of many fruit, nut, vegetable, forage, and field crops. Diazinon also is used in cattle eartags. Approximately 13 million pounds of the active ingredient diazinon are used annually on agricultural sites. Use is highest on almonds and stone fruits.
The IRED concluded EPA's review of diazinon through the OP pilot public participation process, which has increased transparency and maximized stakeholder involvement in the Agency's development of risk assessments and risk management decisions. EPA worked extensively with affected parties to reach the decisions presented in the Diazinon IRED. During the past several years, the Agency has exchanged information on diazinon's uses, risks, and benefits with USDA, other federal and state agencies, registrants, users, the environmental community, concerned citizens, and others. This significant input from stakeholders and interested parties helped EPA reach a decision that, with risk mitigation measures discussed in the IRED, diazinon is eligible for reregistration and meets the FQPA safety standard.
EPA also must consider the cumulative effects of the OP pesticides, which share a common mechanism of toxicity. When the Agency completes its cumulative assessment of the OP pesticides, final tolerance reassessment decisions for diazinon and other OPs will be issued. At that time, EPA may need to pursue further risk mitigation for diazinon to address any risks identified in the OP cumulative assessment.
The Diazinon IRED and related documents are available from the pesticide reregistration status Web page.
Description of Unreasonable Adverse Effect Upon the Environment or Reason Tolerance Does Not Meet Section 408 Safety Standard.
An organophosphate pesticide, diazinon can cause cholinesterase inhibition in humans; that is, it can overstimulate the nervous system causing nausea, dizziness, confusion, and at very high exposures (e.g. accidents or major spills) respiratory paralysis and death.
Earlier, indoor and outdoor residential exposures to diazinon posed risks of concern to children and others; however, those risks are being mitigated through provisions of the December 2000 MOA. More recently, in developing the IRED, diazinon residues in food and drinking water resulting from agricultural uses were found not to pose human dietary risks of concern. While residues attributed to agricultural and residential uses have been detected frequently in surface waters, previous mitigation measures for residential products should result in less frequent detections in water. Without further mitigation limiting children's and others' exposure through food and drinking water, diazinon fits into its own "risk cup."
Occupational exposure to diazinon is of concern to EPA for handlers and applicators of diazinon products, as well as to workers entering fields after diazinon applications. The Agency also has identified ecological risks of concern from diazinon use, particularly to birds, mammals, bees, fish, and aquatic invertebrates. Even with the recommended mitigation measures in the IRED, diazinon's worker and ecological risks still will be above levels of concern, but these risks are offset by strong benefits of diazinon use in fruit and vegetable production.
Benefits information was required for diazinon based on its risks to workers and wildlife. Complete benefits assessments evaluating the economic and agricultural effects of cancellation of diazinon were prepared for crops with over 5% of the crop treated with diazinon. In issuing the Diazinon IRED, EPA requested public comment on these uses, including almonds, apricots, blueberries, broccoli, Brussels sprouts, cabbage, caneberry crop group, carrots, cauliflower, cherries (sweet), cranberries, hops, lettuce, melons, nectarines, onions, peaches, pears, plums, prunes, radishes, strawberries, and tomatoes.
EPA's Plan for Addressing Risks
Residential Risk Mitigation
To reduce risks to children and others, the December 2000 MOA is phasing out and canceling all residential uses of diazinon. All indoor residential use product registrations were canceled and retail sale of these products ended as of December 31, 2002. All outdoor residential use product registrations will be canceled and retail sale must end by December 31, 2004. After that time, a buy-back program will help remove remaining outdoor diazinon residential use products from the market and prevent further sale.
Agricultural and Ecological Risk Mitigation
To mitigate risks to agricultural workers as well as to birds and other wildlife, the following mitigation measures are required by the Diazinon IRED. All deletions and cancellations will be phased in during a 2- to 5-year period.
On July 31, 2002, EPA completed a Reregistration Eligibility Decision (RED) for the chlorinated cyclodiene pesticide endosulfan. EPA determined that endosulfan exceeds its own "risk cup," and poses occupational and ecological risks that constitute unreasonable adverse effects on human health and the environment. However, if certain food uses are deleted and the mitigation measures to prevent contamination of surface waters detailed in the RED are implemented, the Agency believes that endosulfan will "fit" within its risk cup. EPA has concluded that the 80 tolerances for endosulfan meet FQPA safety standards, provided the risk mitigation measures outlined in the RED are fully implemented. EPA also believes that endosulfan's occupational and ecological risks can likely be acceptably mitigated through changes to pesticide labeling and formulations. Accordingly, the Agency has determined that endosulfan is eligible for reregistration provided that: (1) additional required data will confirm this decision for occupational exposures associated with the application of dip treatment to roots or whole plants and ecological risks; and (2) the risk mitigation measures outlined in the RED are adopted, and label amendments are made to reflect these measures. Further, if vulnerable areas in specific geographic areas are identified as a result of a stakeholder process explained in the RED, additional ecological risk mitigation measures may be necessary to protect especially sensitive organisms.
EPA recommends that endosulfan registrants implement the required risk mitigation measures on an accelerated schedule. The Endosulfan RED document includes guidance and time frames for complying with label changes for products containing endosulfan.
Endosulfan is a broad spectrum contact insecticide and acaricide registered for use on a wide variety of vegetables, fruits, cereal grains, and cotton, as well as ornamental shrubs, trees, vines, and ornamental herbaceous plants in commercial agricultural settings. Total average annual use of endosulfan is estimated at approximately 1.38 million pounds of active ingredient, according to Agency and registrant estimates. Crops with the highest average percent crop treated are: eggplant (41%), squash (40%), cantaloupe (31%), sweet potato (31%), broccoli (26%), pears (20%), and pumpkins (20%). Crops with the highest sales in 2001 include: cotton (14.2%), cantaloupe (13.2%), tomatoes (12.2%), and potatoes (8.15%).
Endosulfan was first registered as a pesticide in the U.S. in 1954 to control agricultural insect and mite pests on a variety of field, fruit, and vegetable crops. A 1981 Registration Standard and a 1982 Guidance Document required additional generic and product-specific data for the manufacturing products of the technical registrants. Since the Guidance Document, seven DCIs have been issued concerning the potential formation of chlorinated dibenzo-p-dioxins and dibenzofurans in technical endosulfan products. An additional DCI issued in October 1994 addressed residue chemistry data deficiencies.
In 1991, the technical registrants amended labels to incorporate a 300-foot spray drift buffer for aerial applications between treated areas and water bodies. This setback was adopted in order to address concerns about contamination of water and risks to aquatic organisms. In 2000, the technical registrants amended technical product labels to remove all residential use patterns. When the RED was completed in July 2002, there were 94 endosulfan products registered.
Toxicity. Endosulfan generally has been shown to have high acute oral and inhalation toxicity as well as some dermal toxicity. It is an irritant to the eyes. Endosulfan primarily affects the nervous system. Animal studies indicate that endosulfan causes neurotoxic effects, believed to result from over-stimulation of the central nervous system. Evidence from a chronic oral toxicity study in rats indicates that endosulfan acts as an endocrine disruptor. Further investigation is necessary, however, to determine the relevance and impact of this finding on human health.
Overall Risks. EPA has determined that, without mitigation, endosulfan exceeds its own "risk cup" and poses occupational and ecological risks that constitute unreasonable adverse effects on human health and the environment. Specifically, endosulfan poses dietary (acute food and drinking water), worker, and ecological risks of concern.
Food Risk. Endosulfan's potential acute dietary risks from food sources alone exceed EPA's level of concern. Generally, a food risk estimate that is less than 100% of the acute or chronic Population Adjusted Dose does not exceed the Agency's risk concern. For endosulfan, the most exposed subgroup, children 1-6 years old, is estimated to consume 150% of the acute PAD at the 99.9th percentile of exposure, based on highly refined exposure estimates. This exposure leaves no room in the "risk cup" for exposure via drinking water. The crops that contributed the most to the risks of concern are succulent beans and peas.
Drinking Water Risk. Taking into account the supported uses of endosulfan, EPA concluded that residues in drinking water also are of concern. Drinking water exposure to endosulfan can occur through ground and surface water contamination. The Agency used modeled Tier 2 estimates of endosulfan and endosulfan sulfate to estimate risk for acute exposures. The acute estimated drinking water concentrations for endosulfan are above the acute drinking water level of comparisons (DWLOCs) for infants <1 year and the most sensitive population subgroup, children 1-6 years old.
Aggregate Risk. To conduct an aggregate risk assessment, EPA considered endosulfan exposures resulting from food and drinking water only; the technical registrants are not supporting residential uses. Human health risks from these combined food and drinking water exposures are considered to be above acceptable levels.
Worker Risks. Based on current use patterns of endosulfan, EPA has some short-term dermal and inhalation risk concerns for occupational handlers of endosulfan, including individual farmers or growers who mix, load, and/or apply the pesticide and professional or custom agricultural applicators. The Agency also has risk concerns for agricultural workers re-entering treated fields following applications of endosulfan. Occupational handler risks are of concern for many scenarios, even when maximum PPE are utilized, and also are of concern for some scenarios with engineering controls. For post-application workers, REIs as high as 30 days are necessary in some scenarios to achieve acceptable margins of exposure. In general, post-application risks were higher for wettable powder formulations than for emulsifiable concentrates.
Ecological Risks. Ecological risks are also of concern to the Agency. The environmental risk assessment suggests that exposure to endosulfan could result in both acute and chronic risks of concern for terrestrial and aquatic organisms. Endosulfan exposure has resulted in both reproductive and development effects in nontarget animals, particularly birds, fish and mammals.
EPA's Plan for Addressing Risks
To mitigate the dietary, worker, and ecological risks of concern for endosulfan, the following measures set forth in the RED must be implemented.
Dietary (Food) and Ecological Risk
Dietary (Drinking Water) and Ecological Risk
Given the toxicity and persistence of endosulfan and potential risks to aquatic organisms, EPA developed a number of mitigation measures to reduce the risks to aquatic organisms, outlined in the RED. The Agency believes that these measures will reduce the potential for exposures to aquatic organisms and reduce the overall environmental loading of endosulfan. However, in specific geographic areas where conditions exist that make aquatic organisms especially vulnerable (e.g., shallow, leaky aquifers, highly erodible lands, the presence of especially sensitive organisms, and high use of endosulfan), additional measures may be identified. In order to more fully evaluate the risks in these vulnerable areas; the risk management strategies that may be in place or could potentially be implemented in such areas to reduce exposure; and the benefits of the use of endosulfan in those areas, the Agency plans to work with stakeholders to accomplish this objective. Further, the impacts of atmospheric transport may require additional evaluation during this time period. Additional mitigation measures may be needed following the completion of this process.
Additional Data Required
EPA is requiring numerous additional generic studies for endosulfan, listed in the RED, to confirm its regulatory assessments and conclusions.
On July 31, 2002, EPA completed a Reregistration Eligibility Decision (RED) for the organochlorine lindane, and identified risk mitigation measures necessary to address the human health and environmental risks associated with its use. EPA has determined that currently registered lindane seed treatment products will be eligible for reregistration if the registrants make the changes to the registration terms and conditions specified in the RED document and provide the required data, and if EPA is able to establish all required tolerances for residues of lindane in food.
EPA has determined that all existing tolerances for lindane should be revoked. These tolerances are no longer necessary because all lindane products for which the tolerances were originally established have been canceled. The Agency has identified additional data needed to characterize lindane metabolites in order to complete its assessment of potential dietary risks. Finally, EPA has determined that the use of lindane for seed treatment is likely to result in residues in raw agricultural commodities derived from plants grown from seeds treated with lindane. Therefore, new tolerances are required before the currently registered lindane products may be reregistered. EPA also has determined that a number of changes to the terms and conditions of registration of the seed treatment products are necessary to prevent unreasonable adverse effects on the environment.
EPA is considering whether the Federal Food, Drug, and Cosmetic Act (FFDCA) requires the Agency to include in its aggregate exposure and safety assessment those exposures resulting from use of lindane in pharmaceutical products. Lindane is approved by the Food and Drug Administration (FDA) for use in pharmaceutical products to control head lice and scabies. Although information for assessing exposure and risks is limited, EPA's assessment indicates that while use of lindane as a shampoo for head lice control does not pose risks of concern, use as a lotion for treatment of scabies may cause some adverse effects in some portion of the patient population. EPA has solicited additional information and views that may help it determine how best to approach the public policy and statutory interpretation issues associated with the pharmaceutical uses of lindane.
Initially registered by USDA in the 1940s, the organochlorine insecticide lindane has been approved over the years for use on a variety of fruit and vegetable crops, ornamentals, tobacco, greenhouse plants, forestry, farm animals and premises, and other uses. Tolerances were established for a wide variety of raw agricultural commodities. A number of reviews and regulatory actions affecting lindane have taken place during the past 30 years so that now there are only a very limited number of products containing lindane registered for use as seed treatments; all other uses have been canceled. At present, the only lindane food/feed uses supported for reregistration are pre-plant seed treatment on barley, corn, oats, rye, sorghum, and wheat. A proposed new use of lindane on canola seed was assessed in the RED, however the decision whether or not to approve this use is outside the scope of the RED and will be made separately by EPA after new tolerances are established. Up to 233,000 pounds of active ingredient lindane are used annually in the U.S. for seed treatment. Lindane also is currently approved by FDA for use in pharmaceutical products intended to control head lice and scabies (mites) in humans. Less than 2,000 pounds of active ingredient lindane are used annually for these treatments, according to recent FDA sales data.
The Lindane RED and related documents are available from the lindane Web page.
Toxicity. Lindane primarily affects the nervous system. In acute, subchronic, and developmental neurotoxicity studies and chronic toxicity/oncogenicity studies, lindane was found to cause neurotoxic effects. Lindane also appears to cause kidney (renal) and liver (hepatic) toxicity. There is also some evidence that lindane may act as an endocrine disruptor; however, further investigation is necessary to ascertain the relevance and impact of such findings on public health. In 2001, EPA classified lindane as having "suggestive evidence of carcinogenicity, but not sufficient to assess human carcinogenic potential," based on an increased incidence of benign lung tumors in female mice only. Pursuant to Agency cancer guidelines, quantification of cancer risk was not required.
Overall Risks. EPA's human health risk assessment for lindane indicates some risk concerns. Both acute and chronic risks from food alone are low and not of concern to the Agency. Drinking water risk estimates based on screening-level models from both ground and surface water exposures also are low and do not pose a risk concern for drinking water exposure. There are risk concerns for workers with on-farm use of the dust formulation to treat certain seeds. All other occupational risks of concern are mitigated with the use of personal protective equipment or engineering controls. Ecological risks from the seed treatment use of lindane are of concern; however, the Agency believes the assessment is conservative and overestimates the risks. The pharmaceutical use of lindane to treat head lice does not pose risks of concern to the Agency, but the use of lindane to treat scabies does pose a risk of concern, based on EPA's risk assessment.
Food Risk. EPA assessed dietary risk by estimating exposure to lindane residues from consumption of food and drinking water that can occur over a single-day (acute) or longer (chronic) period of time. The acute and chronic dietary (food) risks are less than 100% of the acute and chronic Population Adjusted Doses for the general U.S. population and all population subgroups. Infants (<1 year) and children (1-6 years) were the most highly exposed population subgroups for acute and chronic exposures, respectively.
Special Populations. Because lindane persists in the environment and has long-range atmospheric transport potential, the Agency performed a supplementary chronic dietary exposure and risk assessment for indigenous Alaskan people whose subsistence diets rely heavily on game. The chronic dietary risks based on consumption of traditional foods generally are not of concern. Although the Agency does not have information on a typical day's diet to assess acute dietary risk, limited residue data indicate that acute dietary risks are unlikely to be of concern.
Drinking Water Risk. Drinking water exposure to lindane can occur through ground and surface water contamination. EPA used models to conduct a screening-level assessment of potential high-end estimates of lindane concentrations in surface and ground water sources of drinking water from seed treatment uses. Based on these currently registered uses, lindane concentrations in surface and ground water are low and not of concern.
Pharmaceutical Use Risk. Lindane has been approved by the FDA as a prescription drug to treat lice and scabies. EPA has conducted an assessment of these uses to determine the risk of a lice or scabies treatment. Based on the Agency's current understanding of available data, EPA does not believe that lindane pharmaceutical products used for treatment of lice pose human health risks of concern, when used in accordance with directions provided on the label. However, exposure to lindane through scabies treatment may result in exposure that would contribute significantly to lindane's aggregate risk.
EPA also estimated the concentrations of lindane in surface water used as a source of drinking water which might result from consumer use of lindane for both lice and scabies treatments, and determined that the acute and chronic drinking water estimated concentrations are extremely low.
Risk from All Registered Lindane Pesticide Exposures. To assess the risks from all lindane pesticide exposures, EPA combined risks from food and drinking water exposure only. For the agricultural seed treatment uses of lindane, both acute and chronic estimated drinking water concentrations are below the corresponding drinking water level of comparisons (DWLOCs) for all drinking water sources. Acute and chronic risks associated with food and drinking water exposures to lindane therefore are not of concern to the Agency.
Occupational Risks. Exposure to lindane is of concern to EPA for some worker scenarios, and certain measures are needed to mitigate these risks. Occupational exposure occurs either on-farm or at commercial seed treatment facilities to farmers or workers who mix, load and/or apply lindane as a seed treatment, and to persons who handle or plant treated seed. Based on the Agency's assessment, on-farm handling of the lindane dust formulation to mix/load and plant treated seed results in risks of concern. To mitigate these concerns, on-farm treatment of wheat, barley, oats, and rye seeds with the dust formulation is considered ineligible for reregistration under the RED. Because of the lower seed planting rate, the on-farm treatment of corn and sorghum seeds with the lindane dust formulation is permitted, provided additional PPE is utilized. Commercial treatment of seeds with the liquid formulation for all registered uses is permitted. Specific PPE for workers who are to treat seeds on-farm or commercially, and handle and plant treated seeds, are specified in the lindane RED document. Also, the Agency has no risk concerns for post-application exposures to agricultural workers, and no risk mitigation measures are necessary beyond a 24-hour restricted entry interval (REI). However, provided the soil is not disturbed and there is no contact with the treated seeds, workers may enter the planted field during the 24-hour REI.
Ecological Risks. EPA's ecological risk assessment suggests that the use of lindane can result in adverse acute and chronic effects to terrestrial organisms, and adverse acute effects to aquatic organisms. Lindane is a potential endocrine disruptor in birds, mammals, and possibly fish. Avian (dietary) aversion toxicity studies and a field study suggest that birds are repelled by treated seeds; hence, the Agency believes that the risk to birds by treating certain seeds with lindane are lower and not of concern. Moreover, EPA believes that the risks for local populations of mammals in areas where lindane treated seeds are planted are low, and that mammals may be similarly averse to eating seeds treated with lindane. Although the assessment indicates acute risks of concerns for freshwater fish and invertebrates, and estuarine marine invertebrates, the screening-level model used to assess these risks has likely produced highly conservative estimates which overestimated the environmental concentrations and resulting risks to aquatic species. Actual aquatic risks are expected to be lower and not of concern, and the Agency is requiring data to confirm this determination.
EPA's Plan for Addressing Risks
To mitigate human health and ecological risks of concern associated with lindane's registered pesticide uses, EPA is requiring implementation of the following measures:
Additional Data Required. EPA is requiring the submission of several additional generic studies, listed in the RED, to confirm its regulatory decision for lindane.
FDA Actions for Addressing Risks
To reduce over-use and increase the safe use of lindane pharmaceutical (i.e., head lice and scabies control) products, FDA is implementing the following measures, discussed further on their lindane Web page:
B. Updates on REDs and IREDs Covered in the First Annual Report
- EPA approved label language in August 2003 that will begin to appear on azinphos-methyl products in the marketplace during the 2004 use season. The approved language implements significant worker and ecological risk reduction measures outlined in the October 30, 2001 Azinphos-methyl IRED.
- EPA worked with USDA and stakeholders to develop clear, enforceable labeling to inform users and address potential risks associated with pesticide spray drifting from target application sites.
- The approved labels include spray drift language that was developed to address azinphos-methyl-specific risk concerns. The language used for azinphos-methyl is not intended to serve as a model for mitigating spray drift risks of other pesticides.
- The label language retains the current generic statement and also requires management practices to mitigate risks from drift associated with azinphos-methyl use that were outlined in the IRED. The generic statement may need to be revised when EPA finalizes its spray drift policy.
- EPA published a FIFRA section 6(f) notice in the Federal Register on September 30, 2002, announcing the Agency's receipt of requests for amendments to delete 22 uses from products containing azinphos-methyl. The follow-up cancellation order will be published shortly.
- The 60-day comment period for the Phosmet IRED closed on January 28, 2002. Approximately 70 comments were received, resulting in changes to the following crops: sweet potatoes; low bush blueberries; highbush blueberries; grapes; and citrus. EPA allowed these changes because either they did not increase risk or data is required to confirm that there is no increase in risk.
- The Agency agreed to allow the option of full PPE in place of closed cabs. This option will be phased out in four years.
- EPA agreed to allow a FIFRA section 24(c) special local needs registration for apple maggot control in Washington state. This use allows PCOs to apply phosmet to residential trees, provided that written warning is given to residents to prevent them from entering treated home orchards.
- EPA is requiring a 14-day REI for harvesting crops at pick your own establishments. These establishments were not included in the original IRED.
- A revised IRED and comment response document will be issued in the near future that will include these revisions.
- The generic and product-specific DCIs were issued on April 9, 2003.
- The generic DCI required the registrant to submit data on biomonitoring of workers, glove feasibility, and use and usage, among other things. EPA is currently reviewing the response to the DCI.
- Federal Register Notices were published on October 16, 2002, March 19, 2003, and June 19, 2003, announcing EPA's receipt of the requests for voluntary cancellation of various phosmet home and garden and veterinary products.
- The Agency received the revised labels for review on July 3, 2002. Resolution of issues about label language for spray drift delayed final approval of the labels; however, the Agency has reinitiated the label review, and plans to complete it by November 30, 2003.
- EPA received an application for amended registration from the propargite registrant on January 17, 2003. Re-entry interval ("REI") exceptions were sought for several harvesting activities.
- A revised application for amended registration was submitted on April 30, 2003. Proposed revisions were based on commodity group concerns regarding runoff and spray drift requirements.
- EPA expects to rule on the registrant's requests for REI exceptions and runoff/spray drift revisions this fall, and subsequently will finalize the propargite registration resulting in revised labeling on propargite products.
- Final resolution of spray buffer issues has been delayed by Endangered Species Act litigation involving salmon habitat in the Pacific Northwest.
As discussed in the first NRDC Annual Report, EPA's plan, set forth in the Azinphos-methyl IRED, includes measures to delete, phase out, or continue under time-limited registrations the crop uses of this organophosphate insecticide to improve worker safety and lessen ecological risk. During the phase-out and time-limited registration periods, a variety of new, more stringent use restrictions are required to protect agricultural workers, including longer REIs and PHIs, reductions in the amount of pesticide applied and number of applications, and prohibitions on most aerial applications. The registrants also must conduct studies and provide data on the effectiveness and feasibility of certain PPE, and must conduct ground water monitoring and worker biomonitoring studies. In addition to the measures to improve worker safety, other mitigation measures to reduce ecological risks include adding buffer zones to protect surface water, improved directions for airblast applications, and enforceable label language to address risks from spray drift.
EPA's plan to reduce worker and ecological risks, as set forth in the Chlorpyrifos IRED, included additional PPE and engineering controls, reductions in application rates, developing additional exposure data, increasing retreatment intervals, reducing seasonal maximum amounts applied, and no-spray setback zones around water bodies. Earlier (in June 2000), EPA had entered into an agreement with the technical registrants of chlorpyrifos to eliminate virtually all homeowner uses, except ant and roach baits in child resistant packaging. All post-construction termite use was canceled as of December 31, 2002, and pre-construction termiticide use may continue at a reduced rate only until 2005, unless exposure data are submitted in 2004 that show that residential risks from this use are not a concern.
Labeling reflecting the mitigation measures set forth in the MOA, specifically directed at reducing exposure to children, has been submitted, reviewed, and is currently reflected on the approximately 300 chlorpyrifos products remaining in the marketplace. In addition, registrants have already amended labels to reflect additional PPE and protective measures for some uses. The Chlorpyrifos IRED, which included generic and product-specific Data Call-In (DCI) notices, was issued to all registrants with products containing chlorpyrifos in March 2003. The DCI responses were due by June 2003. Full implementation of the additional risk mitigation measures specified in the IRED are being accomplished by a second round of label amendments as current registrants submit their required responses to the IRED. EPA first focused on the approximately three dozen agricultural use products for which additional measures to mitigate worker risk were required in the IRED. EPA plans to complete its review of the agricultural use product labels by the end of 2003. Non-agricultural use product labels will be re-reviewed starting in 2004.
As a result of implementation of the MOA and the issuance of the IRED, the number of products containing chlorpyrifos has dramatically decreased, from approximately 850 products before the June 2000 MOA to a current total of approximately 300 products. The Chlorpyrifos IRED transmittal letter advised registrants that if they failed to implement any of the risk mitigation measures in the IRED document, EPA would continue to have concerns about the risks posed by chlorpyrifos and would initiate regulatory actions to address its concerns.
As described in the first NRDC Annual Report and set forth in the Phosmet IRED, risk mitigation measures were necessary to eliminate phosmet exposure in residential settings, improve worker safety, and lessen ecological risks. An OP insecticide, phosmet is widely used in agriculture and provides important pest control benefits, but also poses worker and ecological risks. To address phosmet's risks, 3 uses were to be canceled (use on domestic pets, household ornamentals, and household fruit trees); 9 crop uses would be eligible for time-limited registrations for 5 years if registrations were amended to require additional risk reduction measures; and 33 uses would continue with additional mitigation. To protect agricultural workers during the time-limited registration period, new precautions were needed including increased REIs and PHIs, closed transfer systems, and enclosed cabs or maximum PPE for applicators. To reduce ecological risks, requirements included label language regarding spray drift, inward spraying of outside rows of orchards, limiting application amounts, and prohibiting application during bloom period. Additional generic data were to be required including worker biomonitoring and other studies.
Changes to the IRED
As the first NRDC Annual Report described, the Propargite RED required mitigation measures to address worker and ecological risks. To reduce risks to agricultural workers, the required risk mitigation measures included closed mixing/loading systems for corn and cotton applications, enclosed cockpits for all aerial applications, water soluble packaging for all wettable powder formulations, enclosed cabs for all airblast spray applications, PPE, longer REIs for most crops, and Restricted Use Pesticide classification. To reduce ecological risks, mitigation measures included decreasing seasonal maximum application rates for several crops, adding spray intervals of 21 days for most food crops (28 days for citrus), decreasing the number of cotton applications annually from 3 to 2, adding no-treatment buffer zones around aquatic areas, adding label language to minimize spray drift, and requiring testing to better characterize risks to birds. Other generic studies were also to be required. EPA was to propose several tolerance revocations.
The discussion below provides EPA's current thinking and plans for addressing the cumulative risks of certain groups of chemicals identified as sharing a common mechanism of toxicity. EPA has not developed detailed schedules for the conduct of cumulative risk assessments for the common mechanism groups (CMGs) identified pursuant to the NRDC Consent Decree. The following plans, however, reflect the Agency's overall approach. In particular, EPA generally does not intend to perform a cumulative risk assessment for a CMG until after each individual chemical in the CMG has a complete individual risk assessment, including an aggregate risk assessment. (Among other things, this sequence allows incorporation of risk mitigation measures on each individual chemical in the CMG to be reflected in the assumptions of the cumulative risk assessment.) Because one or more of the chemicals in each CMG listed below are not currently scheduled for an individual IRED in FY 2003, EPA currently projects that individual IREDs for all of the chemicals in each of these CMGs would not be finished any sooner than FY 2004, and expects that assessment of cumulative risks would start in the following fiscal year. In the event that the assessment of cumulative risks for any of these CMGs requires extensive resources, EPA anticipates that it could need two years to complete a revised cumulative risk assessment.
The Agency notes, however, that not all cumulative assessments need to be of the same depth and scope. Thus, early in the cumulative assessment process, it is important to determine the need for a comprehensive risk assessment. This is done by considering the number and types of possible exposure scenarios in conjunction with the associated residue values available. Initial toxicity and exposure information is collected. A screening‑level assessment may be conducted that applies more conservative approaches than would a comprehensive and refined cumulative risk assessment. For example, margins of exposure may be based on no‑observed-adverse‑effect‑ levels (NOAELs) for the common toxic effect rather than modeling dose‑response curves of each chemical member to derive more refined relative potencies and points of departures. For exposure to food, treatment of 100% of crops and tolerance level residues may be assumed for each CMG chemical registered for use on a crop. If a screening‑level analysis including such overestimates of exposure indicates that there is no risk concern, then no further detailed assessment may be necessary. But if this conservative approach indicates a potential for unacceptable risk, then a refined assessment should be conducted. This may engender the need for additional data.
In light of the above, EPA notes that the schedules for the CMGs listed below could change substantially.
A. Pesticide Groups Addressed for the First Time
As indicated above, the cascade of events triggered by atrazine exposure leading to mammary gland tumors in female SD rats is not expected to occur in humans given the species difference in reproductive aging. However, the potential for disruption of the hypothalamic pituitary axis and consequent attenuation of the LH surge leading to other health consequences not associated with reproductive aging (e.g., delay in pubertal development) can not be dismissed. Thus, EPA has determined that the triazine pesticides (with a common mechanism group of atrazine, propazine, simazine, and their chlorometabolites) have a common mechanism of suppression of LH surge and consequent reproductive and developmental effects. It is expected that EPA will complete a preliminary cumulative risk assessment in early 2006; this is contingent on completion of the IREDs for the individual chemicals. The revised Atrazine IRED is expected to be completed by October 31, 2003, while the IRED for simazine is slated for completion in 2005.
B. Update on Pesticide Groups Covered in the First Annual Report
The thiocarbamate pesticides (EPTC, molinate, pebulate, and cycloate) were determined not to share a common mechanism; this is based on neuropathy. As an example, however, EPA has conducted a screening level cumulative risk assessment of these and all other thiocarbamates based on neuropathy, making assumptions that are likely to overstate potential exposure and risk significantly. The preliminary analysis shows that the cumulative margins of exposure (MOE) for population subgroups are greater than 1000, with the exceptions of infants less than one year of age, children one to six years of age, and children seven to 12 years of age (these MOEs are 310, 517, and 783, respectively). Removal of molinate from the Common Assessment Group results in MOEs greater than one thousand for all population subgroups. See "Thiocarbamates: A Determination of the Existence of a Common Mechanism of Toxicity and A Screening Level Cumulative Food Risk Assessment," December 19, 2001 (51 pp, 480k, About PDF).
A subset of the dithiocarbamate pesticides (ziram and metam sodium) was determined not to share a common mechanism based on neuropathy. See "The Determination of Whether Dithiocarbamate Pesticides Share a Common Mechanism of Toxicity," December 19, 2001 (46 pp, 348k, About PDF).
Another subset of the dithiocarbamate pesticides (mancozeb, maneb, and metiram) was determined to share a common mechanism based on thyroid effects. After the individual risk assessments are conducted (IREDs are scheduled to be completed in 2005), EPA will reassess all information to determine whether a screening level or a highly refined cumulative risk assessment is needed. If a highly refined assessment is needed, EPA projects that it would issue its preliminary cumulative risk assessment in fiscal year 2005 and the revised cumulative risk assessment in fiscal year 2006.