Quantification of selected pesticide metabolites in human urine using isotope dilution high-performance liquid chromatography/tandem mass spectrometry

Abstract

The annual domestic use of pesticides is continually increasing, virtually ensuring that everyone is exposed to some level of pesticides on a regular basis through diet or environment. The potential developmental and physical adverse effects these chronic pesticide exposures have on children are of increasing concern. To adequately evaluate the potential adverse effects resulting from these exposures, accurate methods to measure the amount of the pesticide absorbed by the body must be developed. We have developed a sensitive method to measure the urinary metabolites of atrazine, diazinon, malathion, 2,4 -dichlorophenoxyacetic acid ( 2,4 -D ) , and certain synthetic pyrethroids in human urine. In our method, stable isotopically labeled analogues of the metabolites were spiked into the urine, which was subsequently extracted at both a neutral and acidic pH using organic solvents. The extracts were analyzed by highperformance liquid chromatography coupled with tandem mass spectrometry ( HPLC -MS / MS ) using atmospheric pressure chemical ionization. Our method has limits of detection ranging from 20 to 500 ng / l ( parts per trillion ) and relative standard deviations of less than 11%. This method has been used to measure the internal doses of these pesticides in both adults and children ( n = 130 ) with no documented exposure to the pesticides. We detected atrazine and synthetic pyrethroid metabolites in less than 12% of the samples analyzed. The metabolites of 2,4 -D, malathion, and diazinon were detected in 22%, 32%, and 57% of the samples, respectively. Journal of Exposure Analysis and Environmental Epidemiology ( 2000 ) 10, 789 ± 798.

Measurement of pesticides and other toxicants in amniotic fluid as a potential biomarker of prenatal exposure: a validation study.

“…Detection limits, precision, and analytical recovery were similar to urine methods (Baker et al 2000;Barr et al 1999;Beeson et al 1999;Bravo et al 2002;Shealy et al 1996). Metabolites derived from naphthalene, carbaryl, para-dichlorobenzene, ortho-phenylphenol, carbofuran, pentachlorophenol, and OP pesticides were detected in this small sample of amniotic fluid samples, indicating that fetal exposures to these compounds occur as early as 15-18 weeks gestation, possibly during sensitive developmental periods.…”

“…Laboratory methods involved a solid-phase or liquid partitioning extraction with analysis using tandem mass spectrometry and isotope dilution gas chromatography-mass spectrometry/mass spectrometry methods previously developed by the CDC for urine. Detailed descriptions of these analytical procedures are presented elsewhere (Baker et al 2000;Barr et al 1999;Beeson et al 1999;Bravo et al 2002;Shealy et al 1996;Whyatt and Barr 2001). Because amniotic fluid is similar to urine, no major modifications in methodology were required, although minor changes were necessary (described in "Results").…”

Differential Behavioral Responses of <I>Anopheles gambiae</I> (Diptera: Culicidae) Modulate Mortality Caused by Pyrethroid-Treated Bednets

“…Recent studies carried out in the European Union and the United States have shown detectable amounts of pyrethroid metabolites in urine samples from the general population (Schettgen et al, 2002;Baker et al, 2000). No evidence of adverse effects has been reported for such levels of exposure.…”

Biomonitoring of Human Exposure to Triazine Herbicides

“…(58) razvili su metodu tekućinske kromatografi je povezane s tandemnom spektrometrijom masa (LC-MS/MS) uz kemijsku ionizaciju analita pri atmosferskom tlaku za određivanje atrazin merkapturata u urinu. Modifi kacija te metode primijenjena je za određivanje razina atrazin merkapturata u urinu ispitanika iz opće populacije (54). LC-MS/MS uz kemijsku ionizaciju pri atmosferskom tlaku primijenjena je za određivanje 18 specifičnih biomarkera najčešće upotrebljavanih pesticida (56) i za određivanje razina izvornih spojeva i njihovih metabolita u urinu poljoprivrednih radnika (57).…”