Biological Monitoring of Organophosphorus Pesticide Exposure among Children of Agricultural Workers in Central Washington State

A pilot observational exposure study was performed to evaluate methods for collecting multimedia measurements (air, dust, food, urine) and activity patterns to assess potential exposures of young children to pesticides in their homes. Nine children (mean age ¼ 5 years) and their caregivers participated in this study, performed in the Duval County, Florida, in collaboration with the Centers for Disease Control and Prevention and the Duval County Health Department. For all nine children, the total time reported for sleeping and napping ranged from 9.5 to 14 h per day, indoor quiet time from 0 to 5.5 h per day, indoor active time from 0.75 to 5.5 h per day, outdoor quiet time from 0 to 1.5 h per day, and outdoor active time from 0.5 to 6.5 h per day. Each home had one to three pesticide products present, with aerosols being most common. Pesticide inventories, however, were not useful for predicting pesticide levels in the home. Synthetic pyrethroids were the most frequently identified active ingredients in the products present in each home. Fifteen pesticide active ingredients were measured in the application area wipes (not detected (ND) to 580 ng/cm 2 ), 13 in the play area wipes (ND-117 ng/cm 2 ), and 14 in the indoor air samples (ND-378 ng/m 3 ) and the socks (ND-1000 ng/cm 2 ). Cis-permethrin, trans-permethrin, and cypermethrin were measured in all nine homes. Chlorpyrifos was measured in all nine homes even though it was not reported used by the participants. All urine samples contained measurable concentrations of 3-phenoxybenzoic acid (3-PBA). The median 3-PBA urinary concentration for the nine children was 2.2 mg/l. A wide variety of pesticide active ingredients were measured in these nine homes at median concentrations that were often higher than reported previously in similar studies. These data highlight the need for additional observational studies in regions where pesticides are used in order to understand the factors that affect young children's exposures and the education/mitigation strategies that can be used to reduce children's exposures.

Section: Introductionmentioning

confidence: 99%

Multimedia measurements and activity patterns in an observational pilot study of nine young children

Tulve

Egeghy

Fortmann

et al. 2007

“…Since the 1970s, urinary dialkylphosphate (DAP) metabolites of OP pesticides have been quantified in human urine as a dosimeter for exposure and bodily adsorption of OP pesticides (Bradway and Shafik, 1977;Reid and Watts, 1981;Bardarov and Mitewa, 1989;Fenske and Leffingwell, 1989;Weisskopf and Seiber, 1989;Drevenkar et al, 1991;Aprea et al, 1994Aprea et al, , 1996aAprea et al, , b, 1999Aprea et al, , 2000Davies and Peterson, 1997;Loewenherz et al, 1997;Moate et al, 1999;Simcox et al, 1999. Fenske et al, 2000Hardt and Angerer, 2000;Heudorf and Angerer, 2001;Lu et al, 2001;Oglobline et al, 2001a, b;Bravo et al, 2002;CDC, 2002;Cocker et al, 2002;Garfitt et al, 2002a, b).…”

Section: Introductionmentioning

confidence: 99%

Measurement of dialkyl phosphate metabolites of organophosphorus pesticides in human urine using lyophilization with gas chromatography-tandem mass spectrometry and isotope dilution quantification

Bravo

Caltabiano

Weerasekera

et al. 2004

159

153

Urinary dialkylphosphate (DAP) metabolites have been used to estimate human exposure to organophosphorus pesticides. We developed a method for quantifying the six DAP urinary metabolites of at least 28 organophosphorus pesticides using lyophilization and chemical derivatization followed by analysis using isotope-dilution gas chromatography-tandem mass spectrometry (GC-MS/MS). Urine samples were spiked with stable isotope analogues of the DAPs and the water was removed from the samples using a lyophilizer. The dried residue was dissolved in acetonitrile and diethyl ether, and the DAPs were chemically derivatized to their respective chloropropyl phosphate esters. The chloropropyl phosphate esters were concentrated, and analyzed using GC-MS/MS. The limits of detection of the method were in the low mg/l (parts per billion) to mid pg/ml range (parts per trillion) with coefficients of variation of 7-14%. The use of stable isotope analogues as internal standards for each of these metabolites allows for sample-specific adjustment for recovery and thus permits a high degree of accuracy and precision. Use of this method with approximately 1100 urine samples collected from pregnant women and children indicate that the low limits of detection allow this method to be used in general population studies.

“…In a variety of populations, including young children, OP pesticide metabolite concentrations in spot urine samples have been used to estimate exposure (Loewenherz et al, 1997;Aprea et al, 2000;O'Rourke et al, 2000;Adgate et al, 2001). As with other chemicals, where recent exposure is estimated by urinary biomonitoring, most OP pesticide metabolites have short biological half-lives, generally on the order of 2 days or less (WHO, 1986).…”

Section: Introductionmentioning

confidence: 99%

Comparison of organophosphorus pesticide metabolite levels in single and multiple daily urine samples collected from preschool children in Washington State

Kissel

Curl

Kedan

et al. 2004

104

A total organophosphorus pesticide exposure study was conducted in Washington State in 1998 in a sample population of 13 children aged 2.5-5.5 years. The children were roughly split between rural and suburban populations and had been previously identified as having potentially elevated organophosphorus pesticide exposures. One component of the study was urine collection and analysis. Urine samples were collected from each subject up to four times in 24 h in two different seasons. Samples were collected at specific time points: before bed, first morning void, after lunch, and before dinner. Urine samples were analyzed initially for the six nonspecific dialkylphosphate (DAP) metabolites and subsequently for eight specific metabolites including malathion dicarboxylic acid (MDA), 3,5,6-trichloro-2-pyridinol (TCPy), and paranitrophenol (PNP). Relatively large percentages of the urine samples contained quantifiable amounts of two of the nonspecific DAP metabolites (DMTPF97%; DETPF67%), and three of the specific metabolites (MDA (71%), TCPy (79%), and PNP (96%)). A percent deviation analysis was employed to determine which of the spot sample time points was the best predictor of the estimated volume-weighted daily average. Of the four spot samples collected, first morning void samples were consistently found to be the best predictors of weighted-average daily metabolite concentration. This finding also held when the data were creatinine-adjusted. The results of this analysis suggest that if spot sampling is to be conducted as part of a biological monitoring study, first morning void samples should be preferentially collected.