An official website of the United States government.

We've made some changes to EPA.gov. If the information you are looking for is not here, you may be able to find it on the EPA Web Archive or the January 19, 2017 Web Snapshot.

Risk Assessment

Regional Screening Levels (RSLs) - Generic Tables

Tables as of:  

For assistance/questions please use the Regional Screening Levels (RSLs) contact us page.

The RSL and RML default values are available in the Apple Store and the Google Play Store for use on mobile devices.

The screening level (SL) tables are available for download in Excel and PDF formats. All tables are presented with target cancer risk (TR) of 1E-06, however, tables are presented with target hazard quotients (THQ) of 1.0 and 0.1. Use the tables appropriate for your region. These tables are considered ready for use. The tables contain both SL calculations and the toxicity values that were used. The download tables do not include the ingestion of fish exposure pathway, the outdoor worker and the indoor worker exposure to soil exposure pathway that are presented in the User's Guide. These exposure pathways can be considered on a site-specific basis in the Calculator.

You may need a PDF reader to view some of the files on this page. See EPA’s About PDF page to learn more.

Screening Levels (TR=1E-06
THQ=1.0)
(TR=1E-06
THQ=1.0)
(TR=1E-06
THQ=0.1)
(TR=1E-06
THQ=0.1)
Summary Table Loading... Loading... Loading... Loading...
Resident Soil Loading... Loading... Loading... Loading...
Composite Worker Soil Loading... Loading... Loading... Loading...
Resident Air Loading... Loading... Loading... Loading...
Composite Worker Air Loading... Loading... Loading... Loading...
Resident Tapwater Loading... Loading... Loading... Loading...
Resident Soil to Groundwater Loading... Loading... Loading... Loading...
Composite Table (Every Table) Loading... Loading... Loading... Loading...
Other Tables PDF XLS
Chemical Specific Parameters Loading... Loading...
Subchronic Toxicity Values Loading... Loading...
Descriptions of annotations and abbreviations used in RSL tables and calculator output
Annotation/Abbreviation Definition Links to detailed discussion
Toxicity Related
CAS Chemical Abstracts Services Registry Number CAS is a unique numerical identifier assigned to every chemical substance described in the open scientific literature, including organic and inorganic compounds.
SF, SFO, CSFo Oral Slope Factor (mg/kg-day)-1 See section 2.3.3 of the user's guide.
IUR Inhalation Unit Risk (µg/m3)-1 See section 2.3.4 of the user's guide.
RfD or RfDo Chronic Oral Reference Dose (mg/kg-day) See section 2.3.1 of the user's guide.
RfC Chronic Inhalation Reference Concentration (mg/m3) See section 2.3.2 of the user's guide.
I or IRIS EPA's Integrated Risk Information System See section 2.3 of the user's guide and the IRIS website.
P or PPRTV The Provisional Peer Reviewed Toxicity Values See section 2.3 of the user's guide and the PPRTV website.
D or DWSHA Drinking Water Standards and Health Advisories See section 2.5 of the user's guide and the DWSHA website.
O or OPP EPA's Office of Pesticide Programs Human Health Benchmarks for Pesticides See section 2.3 of the user's guide and the Human Health Benchmarks for Pesticides website.
A or ATSDR The Agency for Toxic Substances and Disease Registry minimal risk levels (MRLs) See section 2.3 of the user's guide and the ATSDR website.
C or Cal EPA The California Environmental Protection Agency Office of Environmental Health Hazard Assessment See section 2.3 of the user's guideand the Cal EPA OEHHA website.
Screening toxicity values in an appendix to certain PPRTV assessments See section 2.3 of the user's guide and the PPRTV website.
H The EPA Superfund program's Health Effects Assessment Summary Table See section 2.3 of the user's guide and the  HEAST website.
E Toxicity Equivilence Factors (TEF) applied See section 2.3.5 of the user's guide for description of TEFs for dioxins
W Relative Potencey Factors (RPFs) applied See section 2.3.6 of the user's guide for description of RPFs for polycyclic aromatic hydrocarbons (PAHs)
G

See user's guide section 5

See section 5 of the user's guide for special considerations.
M Mutagen See section 5.17 of the user's guide. Some of the cancer causing analytes in this tool operate by a mutagenic mode of action for carcinogenesis. Special equations are used.
GIABS Fraction of contaminant absorbed in gastrointestinal tract (unitless) See Exhibit 4-1 of the soil screening guidance. Note: if the GIABS is >50% then it is set to 100% for the calculation of dermal toxicity values.
ABS or ABSd Fraction of contaminant absorbed dermally from soil (unitless) See Exhibit 3-4 of the soil screening guidance
Csat Soil saturation concentration (mg/kg) See section 5.12 of the user's guide. The soil saturation concentration, Csat, corresponds to the contaminant concentration in soil at which the absorptive limits of the soil particles, the solubility limits of the soil pore water, and saturation of soil pore air have been reached.
RBA Relative bioavailability factor See section 5.10 of the user's guide. Arsenic screening levels for ingestion of soil are now calculated with the default relative bioavailability factor (RBA) of 0.6.
RSL Related
SL Screening Level See section 1 of the user's guide and FAQ 1.
TR Target Risk See section 5.14 of the user's guide.
THQ Target Hazard Quotient See section 5.14 of the user's guideand FAQ 6.
THI Target Hazard Index See section 5.14 of the user's guide.  and FAQ 6.
SSL Soil Screening Level See section 4.8 of the user's guide.
c or ca Cancer is driving screening level See section 5.14 of the user's guide. Cancer and noncancer screening levels are presented in the supporting tables. The most protective value is chosen for the summary table.
n or nc Noncancer is driving screening level See section 5.14 of the user's guide   Cancer and noncancer screening levels are presented in the supporting tables. The most protective value is chosen for the summary table.
* The noncancer screening level is less than 100 times the cancer screening level See section 5.14 of the user's guide.  Some users of this SL Table may plan to multiply the cancer SL concentrations by 100 to set 'action levels' for triggering remediation or to set less stringent cleanup levels for a specific site after considering non-risk-based factors such as ambient levels, detection limits, or technological feasibility. 
** The noncancer screening level is less than 10 times the cancer screening level See section 5.14 of the user's guide. Some users of this SL Table may plan to multiply the cancer SL concentrations by 10 to set 'action levels' for triggering remediation or to set less stringent cleanup levels for a specific site after considering non-risk-based factors such as ambient levels, detection limits, or technological feasibility. 
m or max The screening level has exceeded the theoretical maximum concentration. See section 5.13 of the user's guide. The ceiling limit of 10+5 mg/kg is equivalent to a chemical representing 10% by weight of the soil sample. At this contaminant concentration (and higher), the assumptions for soil contact may be violated (for example, soil adherence and wind-borne dispersion assumptions) due to the presence of the foreign substance itself.
s or sat The screening level has exceeded the  theoretical absorption limit of the soil. See section 5.12 of the user's guide.  The soil saturation concentration, Csat, corresponds to the contaminant concentration in soil at which the absorptive limits of the soil particles, the solubility limits of the soil pore water, and saturation of soil pore air have been reached. Above this concentration, the soil contaminant may be present in free phase (i.e., nonaqueous phase liquids (NAPLs) for contaminants that are liquid at ambient soil temperatures and pure solid phases for compounds that are solid at ambient soil temperatures). 
DAF Dilution attenuation factor See section 4.8.5 of the user's guide.
U User-provided In user-provided mode all the input values are given a reference of U.
Toxicity Related
ppm parts per million ppm is the number of units of mass of a contaminant per million units of total mass.
ppb parts per billion ppb is the number of units of mass of a contaminant per billion units of total mass.
kg kilogram 1,000 grams
mg milligram 1,000th of a gram
µg microgram 1,000,000th of a gram
m3 cubic meters A volume that is made by a cube that is 1 meter on each side.

For assistance/questions please use the Regional Screening Levels (RSLs) contact us page. For general risk assessment questions, separate from the RSLs, please use the link below.