Environmental Factor – September 2022: NASEM Children’s Environmental Health Theme, EPA Workshop
Early childhood vulnerability to environmental exposures was explored at a four-day National Academies of Sciences, Engineering, and Medicine (NASEM) workshop, held August 1-4. “Children’s Environmental Health: A Workshop on Future Priorities for Environmental Health Sciencesponsored by the U.S. Environmental Protection Agency (EPA), featured several NIEHS scientists and grantees who shared their expertise, offered advice, and discussed how environmental health science can contribute to inform policy.
New research methods for risk assessment, current and emerging environmental risks to children, and environmental influences across the lifespan are just a few of the topics explored by workshop participants.
“Throughout this workshop, we learned how science advances real-world protections while balancing uncertainty with the need to act and prevent,” said the NIEHS grantee. Nsedu Obot Witherspoongeneral manager of the Children’s Environmental Health Network (CEHN) and member of the workshop planning committee. Witherspoon oversees the NIEHS-funded National Coordinating Center for Children’s Environmental Health Research Translation Centers (CEHRT) at Emory University.
“We know that lifelong impacts from environmental exposures, particularly critical windows during development, continue to be present and continuously emerge in our research findings,” she said. “Identifying negative health effects should mobilize action.”
Lifelong risk assessment
Risk assessments could better take into account the increased susceptibility of children to health and potential location-related exposures, and they should take into account the higher susceptibility that exists in infants, children and pregnant women.
For example, the production of chemicals continues to increase and the lifelong effects of certain exposures continue to be discovered. Some remediation strategies shared at the workshop included pushing for safer chemical production, raising public awareness, and expanding protections under existing laws.
But now is the time to broaden our approach, according to Linda Birnbaum, Ph.D., former director of the NIEHS and the National Toxicology Program. “It is time to rethink risk assessment as a prevention tool to articulate cumulative risk within communities with the aim of characterizing risk to children,” she said.
Birnbaum said consistent approaches exist for dealing with individual chemicals and considering different routes of exposure. “Now we are emphasizing looking at exposure across different life stages, which has not often been done, but is important when talking about health risk to children. “, she noted. “So progress is being made. The question that remains is whether and how we should vertically adapt health risk assessment for children to look at cumulative exposures – multichemical exposures – at different times in life.
The caveat here is that the chemical environment is continually changing.
Chemical mixtures: a puzzling complication
Cumulative assessments over time should include mixtures of exposures. NIEHS Beneficiary Brenda Eskenazi, Ph.D.director of the Center for Community Health and Environmental Research at the University of California, Berkeley, pointed out that pesticides are rarely used in isolation.
“When we research pesticides, we talk about mixtures because it’s rare, for example, in agriculture to use just one chemical,” Eskenazi said. Additionally, pesticide exposures are expensive to estimate at $100 to $150 per sample, she added, making repeat samples during a pregnancy or throughout childhood a cost. prohibitive.
Additionally, chemical replacements are a growing concern, said NIEHS Perinatal and Early Life Epidemiology Group scientist Kelly Ferguson, Ph.D., who discussed recent research looking at phthalate exposure in pregnant women. and their effects on fetal and early childhood health and development. Phthalates are a group of chemicals used to make plastics more durableand they are used in personal care products, plastic packaging, vinyl flooring, and garden hoses.
“We saw a decrease in exposure from 2007 to 2018 to all of the phthalate metabolites we measured, and that may sound like very good news; however, at the same time, in the same participants, levels of terephthalate metabolites increased dramatically,” Ferguson said.
Researchers and policy makers could find solutions to protect children’s health in the context of Toxic Substances Control Act (TSCA), which could be used to identify data and policy approaches to act on indicators of harm, according to Tracey Woodruff, Ph.D.director of NIEHS, funded Environmental research and translation for the health center (EaRTH Center) at the University of California, San Francisco (UCSF).
TSCA allows EPA to require reporting, testing requirements, and restrictions for chemical substances and mixtures, and specifically requires EPA to consider risks to sensitive subpopulations that include children and pregnant women. However, certain substances are currently excluded under TSCA, including pesticides.
“Looking at classes of chemicals rather than individual chemicals, which could be done under TSCA, will help solve the problem of not replacing one toxic chemical with another,” Woodruff said.
(Jennifer Harker, Ph.D., is a technical writer-writer in the Office of Communications and Public Liaison at NIEHS.)