- IRIS Summary (PDF) (13 pp, 115 K)
- Status: EPA announced in a 2004 Federal Register Notice that chemicals used as pesticides would not be re-assessed by the IRIS Program. This entry in the IRIS database is preserved at the request of EPA program and regional offices. Additional toxicological information may be found under "Other EPA Information."
Reference Dose for Oral Exposure (RfD) (PDF) (13 pp, 115 K)
Last Updated: 07/01/1989
|System||RfD (mg/kg-day)||Basis||PoD||Composite UF||Confidence|
|Hepatic, Hematologic||7.5 x 10-3||Increased liver weights; increase in methemoglobin||
: 7.5 x 10-1
Reference Concentration for Inhalation Exposure (RfC) (PDF) (13 pp, 115 K)
Not assessed under the IRIS Program.
Weight of Evidence for Cancer (PDF) (13 pp, 115 K)
Last Updated: 08/22/1988
|WOE Characterization||Framework for WOE Characterization|
|C (Possible human carcinogen)||Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1986)|
- Classification is based on the induction of urinary tract tumors (renal pelvis carcinomas and urinary bladder papillomas) and thyroid tumors (adenomas/carcinomas combined) in one animal species (F344 rats) in one study. Trifluralin is structurally similar to ethalfluralin, a carcinogen in the rat.
- This may be a synopsis of the full weight-of-evidence narrative.
Oral Slope Factor:
7.7 x 10 -3 per mg/kg-day
Drinking Water Unit Risk: 2.2 x 10 -7 per µg/L
Extrapolation Method: Linearized multistage procedure, extra risk
Tumor site(s): Urinary, Endocrine
Tumor type(s): Combined renal pelvis carcinomas, urinary bladder papillomas and/or thyroid adenomas and carcinomas (Emmerson et al., 1980)
Not Assessed under the IRIS Program.
- Human Health Benchmarks for Pesticides (HHBP). This database provides human health benchmarks for pesticides that may be present in drinking water.
- Office of Pesticide Programs Pesticide Chemical Search. This database provides links to health effects information and registration status for pesticides.
- Chemistry Dashboard. This database provides information on chemical structures, experimental and predicted physicochemical, and toxicity data.
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