polyunsaturated fatty acid (PUFA) concentrations. The n-3 PUFA are regulators of inflammation while
MeHg may impact the cord cytokine profile and, subsequently, contribute to immune mediated
outcomes. This study aimed to investigate associations between infant MeHg exposure and cord
cytokine concentrations while adjusting for cord PUFA.
Methods: We studied participants in the Seychelles Child Development Study (SCDS) Nutrition Cohort
2 (NC2), a large birth cohort in a high fish-eating population. Whole blood MeHg, serum PUFA and
serum cytokine concentrations (IFN-γ, IL-1β, IL-2, IL-12p70, TNF-α, IL-4, IL-10, IL-13, IL-6 and IL-8) were
measured in cord blood collected at delivery (n = 878). Linear regression examined associations
between infant MeHg exposure and cord cytokines concentrations, with and without adjustment for
cord PUFA. An interaction model examined cord MeHg, cytokines and tertiles of the n-6:n-3 ratio
Results: There was no overall association between cord MeHg (34.08 ± 19.98 μg/L) and cytokine
concentrations, with or without adjustment for PUFA. Increased total n-3 PUFA (DHA, EPA and ALA)
was significantly associated with lower IL-10 (β = -0.667; p = 0.007) and lower total Th2 (IL-4, IL-10 and
IL-13) (β = -0.715; p = 0.036). In the interaction model, MeHg and IL-1β was positive and significantly
different from zero in the lowest n-6:n-3 ratio tertile (β = 0.002, p = 0.03).
Conclusion: Methylmercury exposure from fish consumption does not appear to impact markers of
inflammation in cord blood. The association of cord n-3 PUFA with lower IL-10 and total Th2 cytokines
suggests that they may have a beneficial influence on the regulation of the inflammatory milieu. These
findings are important for public health advice and deserve to be investigated in follow up studies.
- immune response