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 (US 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 x10 -3 per mg/kg-day
Drinking Water Unit Risk: 2.2 x10 -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.
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