The Relationship among Maternal Fish Consumption, Mercury Level, and Health Effects from Fetus to Infant Using a Structural Equation Model: Mothers and Childrenʼs Environmental Health (MOCEH)

Abstract

ISEE-0647 Background and Objective: Prenatal exposure to high levels of mercury have been associated with adverse reproductive outcomes. We examined the relationship among maternal fish consumption, mercury level, and health effects from fetus to infant using a structural equation model. Methods: The collaborating multi-centers for a prospective cohort study of Mothers and Children's Environmental Health (MOCEH) have been built up in 2006 and we enrolled 1,286 women before the second trimester of their pregnancy and their spouses between 2006–2009. A trained nurse interviewed participants to record general information on demographic and socioeconomic factors, health behaviors, and environmental factors. We collected blood and urine samples to measure biomarkers for environmental exposures including heavy metals. We measured the mercury level in blood using atomic absorption spectrophotometry. A structural equation model was used to describe the sequential relationships between environmental factors, mercury level and health effects from fetus to infant. We used AMOS 6.0 (SPSS Inc.) for the structural equation model analysis. Results: Overall, pre-pregnant fish consumption was associated with birth weight and the weight of infants at 6 months of age. Amongst women who consumed blue-backed fish, Trichiurus lepturus and bluefin tuna, the weight of the fetus and the infant was lower in the group with a greater than 50 percentile level of mercury in blood and having higher fish consumption comparted to those fetus’ and infants whose mothers were in the lower 50 percentile for mercury blood level and having lower levels of fish consumption. The path in the model showed that mercury levels in blood directly affected birth weight. After considering environmental factors, we considered that fish consumption might cause increased levels of mercury in blood. Birth weight was indirectly decreased by fish consumption through blood mercury level. Conclusion: More detailed evaluation of the potential adverse effects of pre-pregnant fish consumption may be warranted. Pregnant woman should be cautious of consuming some types of fish due to potential mercury contamination.