Infants and young children spend more than 95% of their time indoors where they receive chronic exposures to semi-volatile organic compounds (SVOCs) from contact with indoor dust due to their increased hand to mouth activity and crawling behavior. Several SVOCs commonly detected in indoor dust are considered chemical obesogens, which are defined as chemicals that alter lipid homeostasis and fat storage, alter metabolic set points, or disrupt energy balance, resulting in fat accumulation and obesity. Several recent studies have suggested that perinatal exposure to obesogens may result in increased odds of obesity in children. Current research also suggests that many of these chemicals compounds act via a mechanism that includes activation of peroxisome proliferator-activated nuclear receptors (PPARs), leading to adipogenesis. Our preliminary studies demonstrate that rats prenatally exposed to an environmentally relevant dust mixture were heavier at birth, and throughout their life. Current approaches to measuring children's exposure to chemicals present in dust have typically relied on simplistic and crude dust ingestion rates, or measurements in serum or urine, the latter being expensive and typically isolated to one or few specific chemicals. Therefore, there is a critical need to provide better estimates of integrated exposure to SVOC mixtures and validate appropriate exposure markers. Given the chronic and sometimes high SVOC exposure that occurs in some homes, we hypothesize that early life exposure to mixtures of SVOCs in indoor dust leads to increased odds of obesity in children, and that these effects are associated primarily with chemicals in dust having high PPAR? and adipogenic activity. To address this hypothesis we have recruited a multi-disciplinary team that will leverage the resources of, and collaborate with, an ongoing NIH funded birth cohort examining associations between prenatal nutrition, secondhand tobacco smoke, and epigenetics modifications on obesity in children. We will conduct a nested case control study with 100 overweight/obese and 100 non-obese toddlers and quantify their prenatal and postnatal exposure to mixtures of SVOCs using targeted and non-targeted (e.g. screening) approaches. House dust samples will be characterized for both adipogenic and PPAR activity using in vitro assays, which will provide greater insight into effects related to actual exposure t dust particles. Associations between obesity (and other health outcomes available in the study), contaminant exposure (individual chemicals and mixtures) and adipogenic/PPAR? activity in dust samples will be examined. This work will contribute new data regarding the potential health impacts from pre- and postnatal exposure to contaminant mixtures present in house dust, and help identify mitigating factors.

Public Health Relevance

Obesity rates in the US, particularly in toddlers, are rapidly climbing and it has been hypothesized that early life exposure to chemicals which act as obesogens may be a contributing factor. The goal of this research is to examine the associations between perinatal exposures to mixtures of SVOCs present in house dust, adipogenic potential of house dust, and obesity outcomes in toddlers. We will also explore the use of handwipes as an improved measure of SVOC exposure in the home environment using both targeted and non- targeted (i.e. screening) approaches to characterize exposure to mixtures of SVOCs. This work will contribute new data regarding the potential health impacts in children from chronic exposure to contaminants present in house dust, and help identify mitigating factors.

Agency
National Institute of Health (NIH)
Institute
National Institute of Environmental Health Sciences (NIEHS)
Type
Research Project (R01)
Project #
5R01ES016099-08
Application #
9099839
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Gray, Kimberly A
Project Start
2007-07-01
Project End
2019-06-30
Budget Start
2016-07-01
Budget End
2017-06-30
Support Year
8
Fiscal Year
2016
Total Cost
Indirect Cost
Name
Duke University
Department
Type
Earth Sciences/Resources
DUNS #
044387793
City
Durham
State
NC
Country
United States
Zip Code
27705
Phillips, Allison L; Hammel, Stephanie C; Hoffman, Kate et al. (2018) Children's residential exposure to organophosphate ester flame retardants and plasticizers: Investigating exposure pathways in the TESIE study. Environ Int 116:176-185
Kassotis, Christopher D; Kollitz, Erin M; Ferguson, Patrick Lee et al. (2018) Nonionic Ethoxylated Surfactants Induce Adipogenesis in 3T3-L1 Cells. Toxicol Sci 162:124-136
Hammel, Stephanie C; Phillips, Allison L; Hoffman, Kate et al. (2018) Evaluating the Use of Silicone Wristbands To Measure Personal Exposure to Brominated Flame Retardants. Environ Sci Technol :
Luz, Anthony L; Kassotis, Christopher D; Stapleton, Heather M et al. (2018) The high-production volume fungicide pyraclostrobin induces triglyceride accumulation associated with mitochondrial dysfunction, and promotes adipocyte differentiation independent of PPAR? activation, in 3T3-L1 cells. Toxicology 393:150-159
Rock, Kylie D; Horman, Brian; Phillips, Allison L et al. (2018) EDC IMPACT: Molecular effects of developmental FM 550 exposure in Wistar rat placenta and fetal forebrain. Endocr Connect 7:305-324
Kassotis, Christopher D; Nagel, Susan C; Stapleton, Heather M (2018) Unconventional oil and gas chemicals and wastewater-impacted water samples promote adipogenesis via PPAR?-dependent and independent mechanisms in 3T3-L1 cells. Sci Total Environ 640-641:1601-1610
Phillips, Allison L; Hammel, Stephanie C; Konstantinov, Alex et al. (2017) Characterization of Individual Isopropylated and tert-Butylated Triarylphosphate (ITP and TBPP) Isomers in Several Commercial Flame Retardant Mixtures and House Dust Standard Reference Material SRM 2585. Environ Sci Technol 51:13443-13449
Baldwin, Kylie R; Phillips, Allison L; Horman, Brian et al. (2017) Sex Specific Placental Accumulation and Behavioral Effects of Developmental Firemaster 550 Exposure in Wistar Rats. Sci Rep 7:7118
Hoffman, Kate; Webster, Thomas F; Sjödin, Andreas et al. (2017) Toddler's behavior and its impacts on exposure to polybrominated diphenyl ethers. J Expo Sci Environ Epidemiol 27:193-197
Hammel, Stephanie C; Hoffman, Kate; Lorenzo, Amelia M et al. (2017) Associations between flame retardant applications in furniture foam, house dust levels, and residents' serum levels. Environ Int 107:181-189

Showing the most recent 10 out of 65 publications