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Protecting Children's Health: an EPA Study Measures the Levels of Commonly Used Chemicals in Homes and Day Care Centers

Child playing with blocks

Few studies have been conducted that examine the ways in which people might encounter chemicals in real-world, everyday situations, such as when using common pesticides (“bug spray”), cleaners, and other household products. This lack of understanding is particularly true for young children, who may be at increased risk of exposure—compared to adults or older children— because they often put things in their mouths and crawl on the ground.  An EPA study, known as CTEPP, is a major step forward in filling that knowledge gap, and is the largest dataset on children’s exposures to chemicals ever assembled to date. Data and results from CTEPP are now available through EPA’s Human Exposure Database System (HEDS).

The Study

The Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) study was designed to determine what commonly used chemicals are found in home and/or day care environments, and if children in these environments encountered those chemicals in the course of their regular, day-to-day activities. The research sought to identify the major routes (i.e., breathing and ingestion), and sources (i.e., dust, food, air, soil, and water) through which children can become in contact with chemicals.

It is important to note that CTEPP was an observation measurement study. No chemicals or products were introduced into the homes or daycare centers and participants were asked to follow their normal daily routines while we collected samples and other types of information (i.e., questionnaires and activity and food diaries).

From 2000-2001, the CTEPP study measured the total exposure of 257 preschool children (ages 2 to 5 years) and their primary adult caregivers to more than 50 different pesticides and other chemicals commonly found in their everyday environments. The participants were from homes and day care centers in six North Carolina and six Ohio counties. Monitoring of each participant was performed over a 48-hour period at their home or day care center, where samples of food, drinking water, air, urine, dust, soil, transferable residues on floors, and surface wipes were collected and analyzed. In all, more than 5,000 personal and environmental samples were collected over the course of the study.

Summary Results of the Study

Results of the CTEPP study indicate that low levels of many chemicals were found in both homes and day care centers. Chemicals found at these locations include pesticides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), phthalates, and phenols. The most frequently detected chemicals were those that are commonly used in the home, products found in the home, or from common processes such as combustion. Many of the chemicals were detected in air, dust, solid food, and/or on hand wipes. Analysis of urine samples indicated that several of the chemicals studied were absorbed into the bodies of the children and adult caregivers. For the children, food was the dominant route of exposure to the most frequently detected chemicals.

The results of this study will be used to inform future decisions on regulations and approval of new pesticides and chemicals for home use.

Study Information

An EPA report, a Pilot Study of Children’s Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) has been published as Volume 1 (Report) and Volume 2 (Appendices). These volumes discuss the results and findings of the study.

Data Availability

In 2006, reports were provided to study participants that discussed the overall results of the study as well as their individual results and recommendations on reducing any existing exposures to these chemicals. The data from this study were made publically available via the Human Exposure Database System (HEDS) in October 2011.

Journal Articles:
Morgan M, Jones P, Calafat A, Ye X, Croghan C, Chuang J, Wilson N, Clifton M, Figuerora Z, and Sheldon L.  Assessing the quantitative relationships between preschool children’s exposures to bisphenol A by route and urinary biomonitoring. Environmental Science and Technology. 2011: 45(12): 5309-5316.

Morgan M, Sheldon L, Croghan C, Jones P, Chuang J, and Wilson K. The reliability of using urinary biomarkers to estimate children’s exposures to chlorpyrifos and diazinon Journal of Exposure Science and Environmental Epidemiology. 2011: 21(3): 280-290.

Morgan M, Sheldon L, Thomas K, Egeghy P, Croghan C, Jones P, Chuang J, and Wilson N. Adult and children’s exposure to 2,4-D from multiple sources and pathways. Journal of Exposure Science and Environmental Epidemiology. 2008: 18: 486-494.

Morgan M, Sheldon L, Croghan C, Jones P, Chuang J, and Wilson N. An observational study of 127 preschool children at their homes and daycare centers in Ohio: Environmental pathways to cis- and trans-permethrin exposure. Environmental Research. 2007: 104: 266-274.

Wilson N, Chuang J,  Lordo R, Morgan M, and Sheldon L. An observation study of the potential exposures of preschool children to pentachlorophenol, bisphenol-A, and nonylphenol at home and daycare. Environmental Research. 2007: 103(1): 9-20.

Morgan M, Sheldon L, Croghan C, Jones P, Robertson G, Chuang J, Wilson N, and Lyu C. Exposures of preschool children to chlorpyrifos and its degradation product 3,5,6-trichloro-2-pyridinol in their everyday environments. Journal of Exposure Analysis and Environmental Epidemiology. 2005: 15: 297−309.

Wilson N, Chuang J, Iachan R, Lyu C, Gordon S, Morgan M, Ozkaynak H, and Sheldon L. Design and sampling methodology for a large study of preschool children’s aggregate exposures to persistent organic pollutants in their everyday environments. Journal of Exposure Analysis and Environmental Epidemiology. 2004: 14: 260-274.

Human Exposure and Atmospheric Sciences

Research & Development | National Exposure Research Laboratory


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