Perchlorate (ClO4) and Perchlorate Salts CASRN 7790-98-9 | IRIS

IRIS

System	RfD (mg/kg-day)	Basis	PoD	Composite UF	Confidence
Endocrine	7 x 10 ^-4	Radioactive iodide uptake inhibition (RAIU) in the thyroid	NOEL : 7 x 10^-3 mg/kg-day	10	High

Reference Concentration for Inhalation Exposure (RfC) (PDF) (22 pp, 157 K) Last Updated: 02/18/2005
Information reviewed but value not estimated.

Weight of Evidence for Cancer (PDF) (22 pp, 157 K) Last Updated: 02/18/2005

WOE Characterization	Framework for WOE Characterization
Not likely to be carcinogenic to humans	Revised Draft Guidelines for Carcinogen Risk Assessment (U.S. EPA, 1999)

Basis:

Under U.S. EPAs 1999 Draft Revised Guidelines for Carcinogen Risk Assessment, perchlorate is not likely to pose a risk of thyroid cancer in humans, at least at doses below those necessary to alter thyroid hormone homeostasis, based on the hormonally-mediated mode of action in rodent studies and species differences in thyroid function.
This may be a synopsis of the full weight-of-evidence narrative.

Not assessed under the IRIS Program.

Not assessed under the IRIS Program.

Additional EPA toxicity information may be available by visiting the following sites:

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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