# Standard Operating Procedures (SOPs) for Residential Exposure Assessments

**APPENDIX A**

Summary of Assumptions for the Residential SOPs

September 16, 1997

**Table A-1. Summary of Assumptions for the Residential SOPs**

Scenario | Assumption | Input Descriptor | Reference | Output Descriptor |

2.1 Turf - Handler | PHED surrogate data | central tendency | PHED V1.1 | central tendency to high-end |

20,000 ft² full lawn | mean to upper percentile | Vinlove and Torla, 1995 | ||

1,000 ft² or 5 gallons spot treatment | upper percentile default values, 5 gallons represent two 2.5 gallon handwand containers | HED | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weigh 39.1 kg | average of median for male/female | U.S. EPA, 1996a | ||

2.2 Turf - Post | 20% of application rate is available as dislodgeable | upper percentile | HED | high-end |

Residue dissipation must be based on chemical-specific data | -- | -- | ||

Adult Tc = 43,000 cm²/hr Toddlers Tc = 8,700 cm²/hr | mean | Cal EPA, 1996 (Tc from carpet study) | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a | ||

Toddlers (3 yrs) and adults exposed 2 hrs/day | 95th percentile for playing on grass is 121 minutes/day for 1 to 4 yrs old and 18 to 64 yrs old | U.S. EPA 1996a | ||

2.3.1 Ingestion of Pellets/Granules - Post | 0.3 g/day ingestion @ age 3 | assumed upper percentile | HED; derived based on application rate of 150 lbs product/ half acre | high-end |

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a | ||

2.3.2 Nondietary Ingestion, Hand-to- Mouth | 20% of the application rate is available as dislodgeable | upper percentile | HED | high-end |

Residue dissipation must be based on chemical-specific data | -- | -- | ||

3 yr old hand surface area 350 cm² | mean of the median total surface areas for males and females in the 2 to 3 and the 3 to 4 yr age groups multiplied by the average percentage of the total body represented by the hands | U.S. EPA 1996a | ||

One-to-one relationship betwen dislodgeable residues on turf and on hands | assumed | -- | ||

Hand-to-mouth activity is 0.026 events/minute for 3 to 5 yr old | mean | U.S. EPA 1996b | ||

Toddlers exposed 2 hrs/day | 95th percentile for playing on grass is 121 minutes/day for 1 to 4 yrs old and 18 to 64 yrs old | U.S. EPA 1996a | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a |

**Table A-2. Summary of Assumptions for the Residential SOPs (continued) **

Scenario | Assumption | Input Descriptor | Reference | Output Descriptor |

2.3.3 Ingestion of Turf | 20 percent of application rate is available for ingestion | upper percentile | HED | high-end |

Residue dissipation must be based on chemical-specific data | -- | -- | ||

3 yr old ingestion rate of 25 cm²/day | upper percentile | HED; assumed to represent handful of grass | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a | ||

2.3.4 Ingestion of Soil | 100 percent of rate is within the uppermost 1 cm and is available for ingestion | upper percentile | HED; assumed | high-end |

Residue dissipation must be based on chemical-specific data | -- | -- | ||

1 to 6 yr old soil ingestion rate of 100 mg/day | mean | U.S. EPA 1996a | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a | ||

3.1 Garden - Handler | PHED surrogate data | central tendency | PHED V1.1 | |

Substitute unit exposure from a hose-end sprayer for the sprinkler/watering can because no other data are available | upper percentile assumption (central tendency value) | assumed | high-end | |

Substitute unit exposure from an aerosol can for the trigger pump because no other data are available | upper percentile assumption (central tendency value) | assumed | ||

10,000 ft² area treatments | upper percentile (large farm-setting or rural garden) | HED | ||

5 gallons of spray treatments | upper percentile (two 2-1/2 gal handwand treatments) | HED | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weigh 39.1 kg | mean of median for male/female | U.S. EPA, 1996a | ||

3.2 Gardens - Post | 20% of the application rate is available as dislodgeable | upper percentile | HED | high-end |

Residue dissipation must be based on chemical-specific data | -- | -- | ||

Tc of 10,000 cm²/hr for adults and 5,000 cm²/hr for youth (10-12 years) | mean | HED | ||

Exposure duration 0.33 hrs/day for toddlers age 1 to 4 yrs and 0.67 hrs/day for adults age 18 to 64 yrs | 95th percentile for working in garden/soil | U.S. EPA 1996a | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weigh 39.1 kg | mean of median for male/female | U.S. EPA, 1996a |

**
Table A-3. Summary of Assumptions for the Residential SOPs (continued)
**

Scenario | Assumption | Input Descriptor | Reference | Output Descriptor |

4.1 Trees - Handler | PHED surrogate data | central tendency | PHED V1.1 | central tendency to hgh-end |

5 gallons for runoff treatment | upper percentile | HED | ||

1 gallon for brush-on treatments | maximum | HED | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weigh 39.1 kg | mean of median for male/female | U.S. EPA, 1996a | ||

4.2 Trees - Post | 20% of the application rate is available as dislodgeable | upper percentile | HED | high-end |

Residue dissipation must be based on chemical-specific data | -- | -- | ||

Tc is 10,000 cm²/hr for adults and 5,000 cm²/hr for youth (10-12 years) | mean | HED | ||

Exposure duration 0.33 hrs/day for toddlers age 1 to 4 yrs and 0.67 hrs/day for adults age 18 to 64 yrs | 95th percentile for working in garden/soil | U.S. EPA 1996a | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weigh 39.1 kg | mean of median for male/female | U.S. EPA, 1996a | ||

5.1 Pools - Handler | PHED surrogate data | central tendency | PHED V1.1 | central tendency |

Pool size 20,000 gallons | mean | Kirk-Othmer 1984 | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weigh 39.1 kg | mean of median for male/female | U.S. EPA, 1996a | ||

5.2.1 Pools - Ingestion | 100 percent of application concentration is available for ingestion and no dissipation | believed to be a reasonable assumption because ai is maintained at specific level in pool | assumed | high-end |

0.05 L/hr ingestion rate for adults and children | mean | U.S. EPA 1989 and Dang 1996 | ||

Exposure duration is 5 hrs/day for children (6 yrs) and adults (18 to 64 yrs) | 90th percentile | U.S. EPA 1996a | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Children (6 yrs) weigh 22 kg | mean of the median values for male and female age 6 yrs | U.S. EPA 1996a |

**Table A-4. Summary of Assumptions for the Residential SOPs (continued) **

Scenario | Assumption | Input Descriptor | Reference | Output Descriptor |

5.2.2 Pools - Absorbed Dose | 100 percent of application concentration is available for ingestion and no dissipation | believed to be a reasonable assumption because ai is maintained at specific level in pool | assumed | high-end |

Exposure duration is 5 hrs/day for children (6 yrs) and adults (18 to 64 yrs) | 90th percentile | U.S. EPA 1996a | ||

Adult body surface area 20,900 cm² and children (6 yrs) body surface area 9,000 cm² | means of the 90th percentiles for females and males | U.S. EPA 1996a | ||

Permeability coefficient (Kp) is chemical specific, see U.S. EPA 1992 for estimating Kp from Kow and MW | -- | U.S. EPA 1992 | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Children (6 yrs) weigh 22 kg | mean of the median values for male and female age 6 yrs | U.S. EPA 1996a | ||

5.2.3 Pools - Inhalation (Post) | 100 percent of application concentration is available for ingestion and no dissipation | believed to be a reasonable assumption because ai is maintained at specific level in pool | assumed | high-end |

Exposure duration is 5 hrs/day for children (6 yrs) and adults (18 to 64 yrs) | 90th percentile | U.S. EPA 1996a | ||

Inhalation rate of 1.7 m³/hr for adults (over 18 yrs) and 1.2 m³/hr for children (under 18 yrs) | mean based on moderate activity | U.S. EPA 1996a | ||

Gas phase conc. based on ideal gas model and Raoult's Law | -- | Dang 1996 | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Children (6 yrs) weigh 22 kg | mean of the median values for male and female age 6 yrs | U.S. EPA 1996a | ||

6.1.1 Painting - Handler | 3 cans/event of aerosol spray @ 12 ounces/cans | 90th percentile (spray paint 36.11 oz/use) | U.S. EPA 1996a | high-end |

2 gallons of paint with a paint brush | 90th percentile (8 gallons/yr) divided by mean frequency of events (4 events/yr) | U.S. EPA 1996a | ||

2 gallons of paint with a paint roller | 90th percentile (8 gallons/yr) divided by mean frequency of events (4 events/yr) | U.S. EPA 1996a | ||

5 gallons with low pressure hand pump deck-type stain sprayer | not assigned | HED | ||

Three 5-gallon cans with an airless sprayer | upper percentile | derived based on coverage rate of 200 ft²/gallon and house size of 40ft x 30ft x 20ft (surface area 2,800 ft²) |

**Table A-5. Summary of Assumptions for the Residential SOPs (continued)**

Scenario | Assumption | Input Descriptor | Reference | Output Descriptor |

6.1.1 Painting - Handler (cont.) | PHED surrogate data | central tendency | PHED V1.1 | |

If paint roller study is not available, assume PHED exposure of the paint brush scenario | central tendency | HED | ||

All paint categories (exterior alkyd and latex) are assumed to be similar | -- | assumed | ||

Default density of spray paint is 1.24 g/mL | mean density of latex paint | U.S. EPA 1986 | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weigh 39.1 kg | mean of median for male/female | U.S. EPA, 1996a | ||

6.3 Ingestion of Paint Chips | Paint chip ingestion rate of 0.04 g/day for 6 month to 1.5 yrs old child | upper percentile | paint chip size ingested is assumed, avg. weight of paint chip U.S. EPA 1994 | high-end/bounding |

Infants (6 months to 1.5 yrs) body weight is 10 kg | mean of median values for male and female children in the 6 to 11 month and 1 yr age groups | U.S. EPA 1996a | ||

20% of ai is remaining and is available for ingestion | upper percentile | HED; professional judgement | ||

7.1 Foggers - Inhalation | Outdoor space (e.g., yard) of 20 ft x 20 ft x 8 ft high = 3,200 ft³ | central tendency | HED; assumed | high-end |

Instant release of ai and dilution factor of 1 to 100 (1 percent) | upper percentile | HED; assumed | ||

2 single use foggers | upper percentile | HED; assumed | ||

Specific gravity of 0.80 g/mL | mean | CRC 1981 | ||

Adult inhalation rate of 0.55 m³/hr or 13.3 m³/day | mean for males and females | U.S. EPA 1996a | ||

Toddlers (age 3) inhalation rate of 0.36 m³/hr or 8.7 m³/day | mean | U.S. EPA 1996a | ||

Exposure duration for adults (18 to 64 yrs) is 5 hrs/day and 3 hrs/day for toddlers (1 to 4 yrs) | 95th percentile for outdoors at restaurant/picnic areas | U.S. EPA 1996a | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a | ||

8.1 Indoor Crack & Crevice - Handler | PHED surrogate data | central tendency | PHED V1.1 | central to high-end |

2 aerosol cans and 2 gallons for low pressure handwands | upper percentile | HED | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weigh 39.1 kg | mean of median for male/female | U.S. EPA, 1996a |

**Table A-6. Summary of Assumptions for the Residential SOPs (continued)**

Scenario | Assumption | Input Descriptor | Reference | Output Descriptor |

8.2.1 Carpets - Post | 50 percent of the application rate is available as dislodgeable. | not assigned | U.S. EPA 1993 | central |

Tc is 43,000 cm²/hr for adults, 8,700 cm²/hr for children, and 6,000 cm²/hr for infants (age 6 months to 1-1/2 years) | mean | U.S. EPA 1996c Cal EPA, 1996 | ||

Exposure duration of 8 hrs/day for adults (18 to 64 yrs) and children (1 to 4 yrs) | mean of the median for adults and children | U.S. EPA 1996a | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a | ||

Infants (6 months to 1.5 yrs) body weight is 10 kg | mean of median values for male and female children in the 6 to 11 month and 1 yr age groups | U.S. EPA 1996a | ||

8.2.2 Hard Surfaces - Post | 50 percent of the application rate is available as dislodgeable. | not assigned | U.S. EPA 1993a | central to high-end |

Tc is 43,000 cm²/hr for adults, 8,700 cm²/hr for children, and 6,000 cm2/hr for infants (age 6 months to 1-1/2 years) | mean | U.S. EPA 1996c Cal EPA, 1996 | ||

Exposure duration is 4 hrs/day | mean of the 90th percentile for adults (18 to 64 yrs) and toddlers (1 to 4 yrs) in the kitchen and bathroom | U.S. EPA 1996a | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a | ||

Infants (6 months to 1.5 yrs) body weight is 10 kg | mean of median values for male and female children in the 6 to 11 month and 1 yr age groups | U.S. EPA 1996a | ||

8.4 Indoor Surfaces - Hand-to-Mouth | 50 percent of application rate is available as dislodgeable | not assigned | U.S. EPA 1996c | high-end |

3 yr old hand surface area 350 cm² | mean of the median of the total surface area for males and females in the 2 to 3 and the 3 to 4 yr age groups multiplied by the average percentage of the total body represented by the hands | U.S. EPA 1996a | ||

Tc is a one-to-one ratio | maximum | assumed | ||

Hand-to-mouth activity rate is 0.026 events/minute for toddlers (3 to 5 yrs old) | mean | U.S. EPA 1996b | ||

Exposure duration is 4 hrs/day | mean of the 90th percentile for adults (18 to 64 yrs) and toddlers (1 to 4 yrs) in the kitchen and bathroom | U.S. EPA 1996a | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a |

**
Table A-7. Summary of Assumptions for the Residential SOPs (continued)
**

Scenario | Assumption | Input Descriptor | Reference | Output Descriptor |

9.1.1 Pets - Handlers (Dips/Shampoo/Dust/Flea Collar) | PHED surrogate data | central tendency | PHED V1.1 | bounding |

Homeowner is exposed to 10 percent of ai applied to pet | upper percentile | HED | ||

Homeowner is exposed to 1 percent of ai in flea collar | upper percentile | HED | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weigh 39.1 kg | mean of median for male/female | U.S. EPA, 1996a | ||

9.1.2 Pets - Handlers (Aerosol) | PHED surrogate data | central tendency | PHED V1.1 | bounding |

Application is the entire contents of product | maximum | assumed | ||

Density of organic spray solution is 0.80 g/mL | mean | CRC 1981 | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weigh 39.1 kg | mean of median for male/female | U.S. EPA, 1996a | ||

9.2.1 Pets - Post | 20 percent of the application rate is available as dislodgeable | upper percentile | HED | high-end |

10 percent of the ai is transferred to the homeowner | upper percentile | HED | ||

No dissipation over time | maximum | assumed | ||

One animal is contacted per day | -- | assumed | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a | ||

9.2.2 Pets - Hand-to-Mouth | 20 percent of the application rate is available as dislodgeable | upper percentile | HED | high-end |

No dissipation over time | -- | assumed | ||

3 yr old hand surface area 350 cm² | mean of the median of the total surface area for males and females in the 2 to 3 and the 3 to 4 yr age groups multiplied by the average percentage of the total body represented by the hands | U.S. EPA 1996a | ||

Pet body surface area of 6,000 cm² (assumed 30 lb pet) | mean | Surface area calc. from U.S. EPA 1993b | ||

Residue transfer is a one-to-one ratio | maximum | assumed | ||

Hand-to-mouth activity for a toddler (3 to 5 yrs) is 0.026 events/minute | mean | U.S. EPA 1996b | ||

Exposure duration is 2 hrs/day for toddlers | upper percentile | HED | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a |

** Table A-8. Summary of Assumptions for the Residential SOPs
(continued)**

Scenario | Assumption | Input Descriptor | Reference | Output Descriptor |

11.2 Impregnated Materials - Post | Skin surface area for mattresses is one-half the total surface area; 1 m² for adults and 0.35 m² for toddlers (age 3 yrs); surface area for shower curtains is one-tenth the total surface area; 0.2 m² for adults and 0.07 m² for toddlers (age 3) | mean | U.S. EPA 1996a | central |

Flux through impregnated materials is assumed the same | -- | assumed | ||

Exposure time for mattresses 8 hrs/day; 0.5 hrs/day for shower curtains | median | U.S. EPA 1996a | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a | ||

11.3 Impregnated Materials - Toddler Ingestion | Surface area of the impregnated material (e.g., toy) is 500 cm² | not assigned | Dang 1997 | high-end |

Entire area of impregnated material is mouthed once per day | -- | HED | ||

Toddlers (3 yrs) weigh 15 kg (represents 1 to 6 yrs) | mean of the median for male/female | U.S. EPA 1996a | ||

13.1 Crack & Crevice - Inhalation Handler Indoors | PHED surrogate data | central tendency | PHED V1.1 | central to high-end |

One aerosol can, 2 gallons of low pressure handwand, one shaker can | upper percentile | assumed | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weight 39.1 kg | mean of median for male/female | U.S. EPA, 1996a | ||

15.0 Pick Your Own | 20 percent of application rate is available as dislodgeable | upper percentile | HED | high-end |

Exposure duration of 2.0 hrs per day for toddlers and 4 hrs for adults | median for time spent outdoors at a farm | U.S. EPA 1996a | ||

Tc is 5,000 cm²/hr for youth and 10,000 cm²/hr for adults | not assigned | HED | ||

Adults (all adults 18+ yrs) weigh 71.8 kg | mean | U.S. EPA 1996a | ||

Female (13 to 54 yrs) weigh 60 kg | mean | U.S. EPA 1996a | ||

Youth (10-12 years) weigh 39.1 kg | mean of median for male/female | U.S. EPA, 1996a |

References:

U.S. EPA (1996a) Exposure Factors Handbook. [Draft]. U.S. Environmental Protection Agency, National Center for Environmental Assessment, Washington, DC. EPA/600/P-95/002Ba.

Cal EPA (1996) Memorandum from T. Formoli (California EPA, Department of Pesticide Regulation, Worker Health and Safety Branch) to M. Mason (California EPA, Department of Pesticide Regulation, Pesticide Regulation Branch), October 17, 1996.

U.S. EPA (1996b) Time location activity pattern methodology: the creation of Bayesian distributions for the field investigations of exposure of infants and children to toxic substances. EPA-007-2. (To be included in an EPA Project Report entitled "Protocol for dermal exposure assessment in residential and non-occupational environments" which is currently in preparation and subject to EPA/ORD peer review).

CRC (1981) CRC Handbook of Chemistry and Physics, 61st Edition. CRC Press Inc. Boca Raton, Florida.

Kirk-Othmer (1984) Encyclopedia of Chemical Technology, 3rd Edition. Vol. 24, p. 427.

U.S. EPA (1989) Risk Assessment Guidance for Superfund. U.S. Environmental Protection Agency, Office of Emergency and Remedial Response, Washington, DC. EPA/540/1-89/002

U.S. EPA (1994) Guidance Manual for the Integrated Exposure Uptake Biokinetic Model for Lead in Children. Prepared by the Technical Review Workgroup for Lead for EPA's Office of Emergency and Remedial Response. EPA 540-R-93-081.

U.S. EPA (1993a) Protocol for Dermal Exposure Assessment: A Technical Report. U.S. Environmental Protection Agency, Environmental Monitoring Systems Laboratory. EPA/600/X-93/005.

U.S. EPA (1993b) Wildlife Exposure Factors Handbook. U.S. Environmental Protection Agency, Office of Research and Development, Washington, DC. EPA/600/R-93/187a.

Dang, W. (1996) The swimmer exposure assessment model (SWIMODEL) and its use in estimating risks of chemical use in swimming pools. EPA internal guidance document.

Vinlove, F.K., Torla, R. (1995) Comprehensive Estimation of U.S. Home Lawn Area. Journal of Turfgrass Management. 1(1):83-97.

U.S. EPA. (1996c) Assessment of Peak Performance System as a Tool for the Acquisition of Biomechanics Data Which May be Useful in the Calculation of Risks to Sensitive Populations. Prepared for the U.S. Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory by Versar, Inc. Under Contract No. 68-D3-0013.

U.S. EPA (1992) Dermal Exposure Assessment: Principles and Applications. Office of Health and Environmental Assessment. EPA/600/8-9/011F.

Dang (1997) Risk Analysis for microban Additive "B" (Triclosan or Irgasan DP300) Treated Toys For Infants, Memo From Winston Dang (Antimicrobial Division) to Frank Sanders and William Jordan (Antimicrobial Division) Dated February 24, 1997.

U.S. EPA (1986) Standard Scenarios for Estimating Exposure to Chemical Substances During Use of Consumer Products -- Volume 1, Prepared for U.S. EPA, Office of Toxic Substances, Exposure Evaluation Division, by Versar, Inc. EPA Contract # 68-02-3968.