Fetal exposure to chlordane and permethrin mixtures in relation to inflammatory cytokines and birth outcomes

We sought to characterize the relationships between cord serum concentrations of chlordane and permethrin pesticides, inflammatory cytokines, gestational age, and size at birth. Umbilical cord serum levels of trans-nonachlor, oxychlordane, cis-and trans-permethrin, piperonyl butoxide, and cytokines (TNF-α, IFN-γ, IL-1β, IL-2, IL-6, IL-8, IL-10, IL-12p70, GMCSF) were quantified in 300 newborns at the Johns Hopkins Hospital in Baltimore, MD (2004-2005). Principal component analyses were used to quantitate chlordane and permethrin mixtures and to identify independent cytokine components. Five cytokine components described 87% of the variance in cord serum cytokine levels; these (and predominant loadings) were as follows: (1) all 9 cytokines; (2) acute phase (IL-1β, IL-6); (3) anti-inflammatory (IL-10); (4) TNF-α and (5) IL-1β. Of these, the TNF-α component was significantly associated with a 2-day decrease in gestational age. Chlordane was associated with lower levels of the pro-inflammatory IL-1β [β:-0.11 (-0.20,-0.02)]. Permethrin was negatively associated with the anti-inflammatory cytokine IL-10 [β:-0.14 (-0.22,-0.05)]. Neither pesticides nor cytokines were significantly associated with birthweight, length, or head circumference, and pesticides were not associated with gestational age. Our findings suggest that chlordane and permethrin concentrations in cord blood may be associated with levels of inflammatory cytokines in the fetus.