Measurement of p-nitrophenol in the urine of residents whose homes were contaminated with methyl parathion.

Abstract

We thank all the state and local health officials involved with sample collections and shipments. Throughout the period of laboratory-based measurements, many people provided invaluable assistance in biomonitoring that contributed to the rapid turnaround of data. We thank D. Methyl ParathionDuring the last several years, illegal commercial application of methyl parathion (MP) in domestic settings in several U.S. Southeastern and Midwestern States has affected largely innercity residents. As part of a multiagency response involving the U.S. Environmental Protection Agency (U.S. EPA), the Agency for Toxic Substances and Disease Registry (ATSDR), and state and local health departments, our laboratory developed a rapid, high-throughput, selective method for quantifying p-nitrophenol (PNP), a biomarker of MP exposure, using isotope dilution high-performance liquid chromatography-tandem mass spectrometry. We measured PNP in approximately 16,000 samples collected from residents of seven different states. Using this method, we were able to receive sample batches from each state; prepare, analyze, and quantify the samples for PNP; verify the results; and report the data to the health departments and ATSDR in about 48 hr. These data indicate that many residents had urinary PNP concentrations well in excess of those of the general U.S. population. In fact, their urinary PNP concentrations were more consistent with those seen in occupational settings or in poisoning cases. Although these data, when coupled with other MP metabolite data, suggest that many residents with the highest concentrations of urinary PNP had significant exposure to MP, they do not unequivocally rule out exposure to PNP resulting from environmental degradation of MP. Even with their limitations, these data were used with the assumption that all PNP was derived from MP exposure, which enabled the U.S. EPA and ATSDR to develop a comprehensive, biologically driven response that was protective of human health, especially susceptible populations, and included clinical evaluations, outreach activities, community education, integrated pest management, and decontamination of homes.

Biotransformation of methyl parathion by marine-derived fungi isolated from ascidian Didemnum ligulum

“…PNP may undergo conjugation with other molecules (Barr et al, 2002). The conjugation reactions are catalyzed by enzymes and are common in biotransformation processes of xenobiotics, usually promoting binding of toxic compounds slightly polar to more polar molecules, facilitating the excretion of the compound (Costa et al, 2004).…”

A liquid chromatography/electrospray ionization?tandem mass spectrometry method for quantification of specific organophosphorus pesticide biomarkers in human urine

“…LODs have been reported that range from 0.05 to 2 ng/mL for the major urinary metabolites of chlorpyrifos and parathion [3, 11,12] and from 0.5 to 1 ng/mL for the major metabolite of diazinon [13]. Several high-performance liquid chromatography (HPLC) tandem mass spectrometry (MS/MS) methods for the measurement of OP metabolites in urine also has been published [4,6,13,14,15]. HPLC-MS/MS analysis, using atmospheric pressure chemical ionization (APCI), of specific metabolites of diazinon and malathion have been reported, with LODs <0.5 ng/mL [4,7].…”

Introduction--the methyl parathion story: a chronicle of misuse and preventable human exposure.

“…The extent of potential human exposure to this pesticide led ODH to formally request technical assistance from the Centers for Disease Control and Prevention (CDC). This article describes the initial investigation in Ohio and supports the importance of using both biological markers of exposure (1,2) and environmental markers of contamination (3) when making public health decisions about the cleanup of methyl parathion-sprayed homes.…”