Use of short-term toxicity data for prediction of long-term health effects

Conference · Fri Jan 01 04:00:00 EST 1988 · Trace Subst. Environ. Health; (United States)

OSTI ID:5963145

Hartley, W R; Ohanian, E V

Under the Safe Drinking Water Act Amendments of 1986, the US Environmental Protection Agency determines Maximum Contaminant Level Goals (MCLGs) and enforceable Maximum Contaminant Levels (MCLs) or provides lifetime health advisories (HAs) in the absence of regulatory standards. The critical value for calculation of the lifetime level is the reference dose (RfD). The RfD is an estimate of a lifetime dose which is likely to be without significant risk to human populations. The RfD is determined by dividing the no-observed-adverse-effect level (NOAEL) or the lowest-observed-adverse-effect level (LOAEL) by an uncertainty factor (UF). The NOAEL or LOAEL is determined from toxicological or epidemiological studies. For many chemicals, human toxicological or epidemiological data are not available. Chronic mammalian studies are sometimes unavailable. Faced with the need for providing guidance for the increasing number of chemicals threatening our drinking water sources, this paper considers the possibility of providing provisional RfDs using data from toxicological studies of less than ninety days duration. The current UF approach is reviewed along with some proposed mathematical models for extrapolation of NOAELs from dose-response data. The current UF approach to developing the RfD is protective and conservative. More research is needed on the relationship of short- and long-term toxicity data to improve our current approach.

• Research Organization: Environmental Protection Agency, Washington, DC (USA)
• OSTI ID: 5963145
• Report Number(s): CONF-8805159-
• Conference Information: Journal Name: Trace Subst. Environ. Health; (United States) Journal Volume: 12
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CHRONIC EXPOSURE
CONTAMINATION
DOSE-RESPONSE RELATIONSHIPS
DRINKING WATER
FORECASTING
HAZARDS
HEALTH HAZARDS
HYDROGEN COMPOUNDS
MATHEMATICAL MODELS
MAXIMUM PERMISSIBLE EXPOSURE
OXYGEN COMPOUNDS
RISK ASSESSMENT
SAFETY STANDARDS
STANDARDS
WATER
XENOBIOTICS