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A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP)
Citation:
Morgan, M K., L S. Sheldon, C Croghan, J. C. Chuang, C. Lyu, N K. Wilson, R. A. Lordo, M. C. Brinkman, N. Morse, Y. L. Chou, C. Hamiltin, J. K. Finegold, K. Hand, AND S. M. Gordon. A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-04/193 (NTIS PB2006-101286), 2005.
Impact/Purpose:
The overall objectives of CTEPP were to measure the aggregate exposures of approximately 260 preschool children and their adult caregivers to low levels of a suite of pesticides and organic pollutants that the children may encounter in their everyday environments, and to apportion the routes of exposure and estimate the relative contributions of each route.
Description:
The Pilot Study of Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) investigated the aggregate exposures of 257 preschool children and their primary adult caregivers to pollutants commonly detected in their everyday environments. The target compounds include organophosphate (OP) pesticides, OP metabolites, organochlorine (OC) pesticides, pyrethroid pesticides and metabolites, acid herbicides, polycyclic aromatic hydrocarbons (PAH), phthalates, phenols, polychlorinated biphenyls (PCB), PAH metabolites, and atrazine. Some of the target compounds are persistent indoors and sometimes outdoors, so that very low levels may exist in the children's surroundings and provide a source of non-acute exposure. The primary purposes of the research were to increase the understanding of children's exposures to persistent and non-persistent organic pollutants, and to gain information on the various activities, environmental media, and pollutant characteristics that may influence children's exposures. The overall objectives were to measure the aggregate exposures of approximately 260 preschool children and their adult caregivers to low levels of a suite of pesticides and other organic pollutants that the children may encounter in their everyday environments and to apportion the routes of exposure and estimate the relative contributions of each route. Within these objectives, four major, specific goals for the CTEPP study were accomplished in this report. These goals were: (1) to measure the concentrations of the target pollutants in multimedia samples collected at the homes and at day care centers of preschool children in six North Carolina (NC) counties and six Ohio (OH) counties, (2) to determine the distributions of child characteristics, activities, and locations that contributed to their exposures, (3) to estimate the aggregate exposures of the preschool children to these pollutants that they may encounter in their everyday environments, and (4) to apportion the routes of exposure. Results will also be used to identify important hypotheses to be tested in future research.
A two-state sampling plan was used to select and recruit study participants. In each state, a total of four urban and two rural counties were randomly selected. The counties were located in three distinct geographical regions of each state. These regions were the mountains, the Piedmont, and the coastal plain of NC, and the northern, central, and southern regions of OH. Dual sampling frames (the day care and the telephone components) were used in each state. To recruit participants in households whose children attended child day care centers, 13 centers in the six NC counties and 16 centers in the six OH counties were selected using probability sampling. Children were then selected randomly from classrooms having children in the eligible age group of two to five years, and their participation was recruited through their parents. To recruit participants in households whose children did not attend child day care centers, list-assisted, random digit dialing telephone sampling in the selected counties was used.
The calculated response rates in NC were 53% for day care centers and 50% for day care parents. In OH these response rates were 57% for OH day care centers and 31% for OH day care parents. The calculated response rate for the telephone sample was 58% in NC and 57% in OH. In NC, children and their caregivers in 130 households participated in the study; in OH, 127 households participated. Approximately half of the children in each state attended child day care centers (63 in NC and 58 in OH). About 84% of the NC participants and 87% of the OH participants lived in urban locations. Low-income households, classified according to federal guidelines for the Women, Infants, and Children (WIC) program (185% of the federal poverty level), comprised 46% of the sampled households in NC and 38% of those in OH.
More than 5,000 discrete personal and environmental samples, including quality control samples, were collected in each state and analyzed. Additionally, house/building characteristics observation surveys, pre- and post-monitoring questionnaires, day care food menus, and detailed child/adult time-activity and food diaries provided ancillary information necessary to estimate aggregate exposures and to aid in interpretation of the CTEPP data.
Field sampling for the day care component took place over a 48-h period at each child's day care center and simultaneously at his/her home. Field sampling for the telephone component took place over a 48-h period at each participant's home. Environmental samples included indoor and outdoor air, outdoor play area soil, indoor floor dust (carpet dust) or if no carpet, hard floor surface wipes, and household/day care drinking water. Personal samples included duplicate diet, hand wipes, and urine. If a pesticide had been applied in the seven days prior to or during sampling, transferable residues, hard floor surface wipes and food preparation surface wipes were also collected. Approximately 10% of the children were videotaped for about 2 h at their homes in OH during sampling to supplement and validate the activity diaries and observations.
All samples, including quality control samples, were extracted, and then analyzed by gas chromatography/mass spectrometry for over 50 target compounds. These compounds included two organopnospnorus (OP) pesticides,two OP metabolites, ten organochlorine (OC) pesticides, one pyrethroid metabolite, three acid herbicides, nine polycyclic aromatic hydrocarbons (PAHs), six PAH metabolites, two phthalates, three phenols, 17 polychlorinated biphenyls (PCBs), and atrazine. These compounds, with the exception of atrazine, PAH metabolites and pyrethroid metabolites, were analyzed in the environmental and personal samples. Atrazine was analyzed only in drinking water samples. Only one OP metabolite, 3,5,6-trichloro-2-pyridinol (3,5,6-TCP), was analyzed in the NC environmental and personal samples; both 2-isopropyl-6-methyl-4-pyrimidinol (IMP) and 3,5,6-TCP were measured in the OH samples. In the NC urine samples, two OP metabolites; IMP and 3,5,6-TCP; 2,4-dichlorophenoxyacetic acid (2,4-D), two hydroxy PAHs: 1-hydroxybenz[a]anthracene and 3-hydroxychrysene; and pentachlorophenol were analyzed. In the OH urine samples, these same metabolites and/or parent compounds were analyzed, in addition to five hydroxy PAHs (1-hydroxypyrene, 3-hydroxybenz[a]anthracene, 3-hydroxybenzo[a]pyrene, 6-hydroxychrysene, and 6-hydroxyindeno[l,2,3-cd]pyrene) and 3-phenoxybenzoic acid (3-PBA).
Two similarly formatted CTEPP databases were developed, one for the NC study and one for the OH study. Each database contained questionnaire data, analytical data, and metadata, and provided sufficient documentation to allow the data to be understood by a diverse set of users. Descriptive statistics were calculated for sample size, mean, standard deviation, percentage detected, minimum and maximum reported values, and selected percentiles (25th, 50th, 75th , and 95th ). The distributions of participant characteristics, activities, and locations that are important for exposure were quantified, based on the questionnaire data. Potential exposures and potential absorbed doses were estimated for selected target compounds, based on the percentage of the samples that had detectable levels of these compounds, the measured concentrations, the participants' activity patterns, and assumed physiological parameters. Statistical analyses to meet the four goals of the study were performed on log-transformed data, using analysis of variance (ANOVA) models. The data summaries presented in this report represent only the children and their primary caregivers in NC and OH who participated in this study.
The information in this document has been funded wholly by the United States Environmental Protection Agency under EPA contract number 68-D-99-011 to Battelle Memorial Institute. It has been subjected to the Agency's peer and administrative review and has been approved for publication as an EPA document. Mention of trade names or commercial products does not constitute endorsement or recommendation for use.
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A PILOT STUDY OF CHILDREN'S TOTAL EXPOSURE TO PERSISTENT PESTICIDES AND OTHER PERSISTENT ORGANIC POLLUTANTS (CTEPP) (PDF, NA pp, 2260 KB, about PDF)CTEPP_APPENDIX.PDF (PDF, NA pp, 5728 KB, about PDF)