Joint exposure to chemical and nonchemical neurodevelopmental stressors in u.s. reproductive-aged women: National health and nutrition examination surveys (NHANES) 2003–2004
Background: Although exposures to lead (Pb) and methyl mercury (MeHg) are well established neurotoxicants, exposure to chemical and nonchemical stressors (e.g., maternal stress) has rarely been considered. We characterized exposure to chronic stress and neurodevelopmental toxicants (NDTs) and identify vulnerable women. Methods: Using data from the 20032004 NHANES, chronic stress was quantified using a measure of cumulative physiological dysregulation, allostatic load (AL), based on 10 biomarkers/biometrics. A Hazard Index (HI) was calculated for joint exposure to Pb and MeHg, HI(NDT). Logistic regression was used to assess the relationship sociodemographic, lifestyle, and nutrition variables and an elevated HI(NDT). The final adjusted model was stratified by chronic stress categories to examine effect modification. Results: After controlling for country of birth, age, education, smoking, and iron status, African Americans (Odds Ratio [OR]; 95% confidence interval [CI] = 2.2; 1.4, 3.3) and Mexican Americans (1.4; 0.8, 2.6) were more likely to have an elevated HI(NDT) compared to Caucasians. Chronic stress was an effect modifier: Odds ratios for both African Americans and Mexican Americans were largest among women with high stress (4.3; 2.0, 9.5 and 4.2; 1.3, 14.1, respectively). Discussion: Chronic stress was found to modify the association between race/ethnicity and exposure to NDTs. This research highlights the importance of evaluating joint chemical and nonchemical exposures with a common endpoint and could be used to identify vulnerable populations. *The views expressed in this abstract are those of the authors and do not necessarily reflect the views or policies of the U.S. EPA.
Environmental health sciences
Social and behavioral sciences
Define cumulative risk assessment (CRA).
Compare traditional risk assessment and CRA.
Explain why it is important to evaluate exposures to multiple chemical and nonchemical stressors with a common endpoint.
Describe the hazard index approach for examining joint hazard to multiple stressors.
Keyword(s): Environmental Exposures, Hazards
Presenting author's disclosure statement:
Qualified on the content I am responsible for because: I have been a research fellow at the EPA for three years examining the incorporation of multiple chemical and nonchemical stressors exposures in human health risk assessment. I have previously published in the peer-reviewed literature regarding this topic.
Any relevant financial relationships? No
I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines,
and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed
in my presentation.