4196.0: Tuesday, October 23, 2001 - 3:00 PM

Abstract #28993

Concentrations of dialkyl phosphate metabolites of organophosphate pesticides in the U.S. population

Dana B. Barr, PhD1, Roberto Bravo, PhD1, Ralph D. Whitehead, BS1, Susan E. Schober, PhD2, James Pirkle, MD, PhD1, and Larry L. Needham, PhD1. (1) Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, 770-488-7950, DBarr@cdc.gov, (2) National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, MD

Organophosphate pesticides (OPs) are widely used in both agricultural and residential settings. Although individual OPs differ in relative toxicity, they have a common acute mechanism of action, cholinesterase inhibition, and they metabolize rapidly in vivo to six common dialkyl phosphates (DAP) that are excreted in urine. Because of their extensive use and their common functional characteristics, the OPs were among the first pesticides to be regulated under the Food Quality Protection Act of 1994 (FQPA). Consequently, CDC has attempted to follow the U.S. EPA's implementation of the FQPA by assessing cumulative human exposure to OPs before and after its implementation as estimated by biological monitoring.

We have measured DAP concentrations in subsets of the Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994) and a representative subset of NHANES 1999. We will compare data from both surveys. Our data indicate that low-level exposure to OP pesticides is ubiquitous and that most of the specimens tested had detectable, albeit low, levels of one or more OP metabolites. Additional data from the continuing NHANES will allow us to evaluate the impact of stricter food tolerances.

See www.cdc.gov/nceh/dls

Learning Objectives: 1. Articulate the common mode of toxicity and general metabolism of organophosphate pesticides. 2. Relate the general population data to documented poisoning cases to gain perspective on exposure ranges. 3.Describe the potential of these data for evaluating the impact of legislation.

Keywords: Pesticide Exposure, Environmental Exposures

Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: None
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.

The 129th Annual Meeting of APHA