Children’s environmental chemical exposures in the USA, NHANES 2003–2012

Abstract

Children are vulnerable to environmental chemical exposures, but little is known about the extent of multiple chemical exposures among children. We analyzed biomonitoring data from five cycles (2003-2012) of the National Health and Nutrition Examination Survey (NHANES) to describe multiple chemical exposures in US children, examine levels of chemical concentrations present over time, and examine differences in chemical exposures by selected demographic groups. We analyzed data for 36 chemical analytes across five chemical classes in a sample of 4299 children aged 6-18. Classes included metals, pesticides, phthalates, phenols, and polycyclic aromatic hydrocarbons. We calculated the number and percent of chemicals detected and tested for secular trends over time in chemical concentrations. We compared log concentrations among groups defined by age, sex, race/ethnicity, and poverty using multiple linear regression models and report adjusted geometric means. Among a smaller subgroup of 733 children with data across chemical classes, we calculated the linear correlations within and between classes and conducted a principal component analysis. The percentage of children with detectable concentrations of an individual chemical ranged from 26 to 100%; the average was 93%, and 29 of 36 were detected in more than 90% of children. Concentrations of most tested chemicals were either unchanged or declined from earlier to more recent years. Many differences in concentrations were present by age, sex, poverty, and race/ethnicity categories. Within and between class correlations were all significant and positive, and the principal component analysis suggested a one factor solution, indicating that children exposed to higher levels of one chemical were exposed to higher levels of other chemicals. In conclusion, children in the USA are exposed to multiple simultaneous chemicals at uneven risk across socioeconomic and demographic groups. Further efforts to understand the effects of multiple exposures on child health and development are warranted.

Brominated Flame Retardants and Organophosphate Esters in Preschool Dust and Children’s Hand Wipes

“…Exposure to BPA, assessed by urinary measurements, has decreased in US children [197,198] and adults [199], and in Swedish women [200]. The few existing time trend studies of BPA analogues in urine have found increasing levels of BPS in US adults [199] and increasing levels of BPF in Swedish women [200].…”

Exposure to New Emerging Bisphenols Among Young Children in Switzerland

“…There is a need to characterize the various exposure sources of BP analogues in consumer and childcare products as well as in the indoor environment. Furthermore, as a consequence of restrictions on the use of BPA in consumer products, urinary BPA levels have decreased steadily over time in USA and EU populations [ 73 ], while urinary BP analogues levels are now on the rise. Despite the extensive amount of experimental data generated for BPA, our ability to link chronic low-dose environmental exposure to BPA with adverse human health effects remains so far limited.…”

Disruption in Thyroid Signaling Pathway: A Mechanism for the Effect of Endocrine-Disrupting Chemicals on Child Neurodevelopment

“…People are ubiquitously exposed to phthalates, non-persistent synthetic chemicals that are used in plastic and consumer products such as cosmetics, adhesives, and detergents. Some forms of phthalates such as di-2-ethylhexylphthalate (DEHP) are no longer used in baby toys; yet phthalates metabolites remain detectible in individuals across age groups ( 111 , 112 ). Urinary phthalates are cross-sectionally associated with lower fT4 and higher TSH ( 99 , 113 , 114 ).…”