Prenatal Exposure to Polychlorinated Biphenyls and Their Hydroxylated Metabolites is Associated with Neurological Functioning in 3-Month-Old Infants

Abstract

Polychlorinated biphenyls (PCBs) are environmental chemicals which are potentially toxic to the developing brain. Their hydroxylated metabolites (OH-PCBs) are suggested to be even more toxic. Knowledge about the health effects of prenatal OH-PCB exposure is limited. We aimed to determine whether prenatal background exposure to PCBs and OH-PCBs is associated with neurological functioning in 3-month-old boys and girls. In a Dutch observational cohort study, we measured 10 PCBs and 6 OH-PCBs in maternal blood samples of 98 pregnant women. We assessed their infants neurologically with Touwen examination at 3 months and calculated an Optimality Score (OS, range 0-53, low-high optimality). We calculated correlation coefficients between compound levels and OS. Subsequently, we tested whether levels were associated with specific clusters and whether levels differed between infants with "normal" (dysfunction on ≤1 cluster) and "non-optimal" development (dysfunction on ≥2 clusters). The mean OS was 48 (range 44-52). Higher exposure to PCB-146 correlated significantly with higher OS (r = 0.209; p = 0.039). In boys, higher exposure to 4-OH-PCB-107 correlated with lower OS (r = -0.305; p = 0.030). Higher exposure to 9 PCBs and the sum of all PCBs was associated with better visuomotor and/or better sensorimotor function. Infants classified as "non-optimal" (n = 36) had significantly lower prenatal exposure to 6 PCBs and the sum of all PCBs (p < 0.05) compared with infants classified as "normal" (n = 62). In conclusion, higher prenatal exposure to Dutch background PCB levels is associated with better neurological functioning in 3-month-old infants. Prenatal exposure to 4-OH-PCB-107 is associated with less optimal neurological functioning in boys.

Developmental neurotoxicants and the vulnerable male brain: a systematic review of suspected neurotoxicants that disproportionally affect males

“…In human infants, Berghuis et al (2014) also found that prenatal exposure to PCBs (mainly 4-OH-PCB-107) was associated with less optimal neurological functioning in boys. In their observational cohort study, they found measurable levels of 10 PCBs and 6 OH-PCBs in maternal blood samples from 98 pregnant women.…”

“…Evidence suggests that exposure to organochlorine pesticides and their metabolites can result in impaired motor and cognitive development in newborns and infants (Saeedi Saravi and Dehpour 2016), especially in visuomotor and sensorimotor functions (Berghuis et al 2014). The nigrostriatal dopamine pathway appears to be one of the target systems in the brain (Wilson et al 2014).…”

Hydroxylated polychlorinated biphenyl metabolites (OH-PCBs), maternal smoking and size at birth

“…Previous studies have explored its effect on neurodevelopment [22, 24, 45]. Park et al (2009) found a significant association between maternal concentrations of 4-OH-CB107 and decreased scores on the Mental Development Index of the Bayley Scales of Infant Development in children aged 16 months in a Slovakian cohort [21].…”

“…Park et al (2009) found a significant association between maternal concentrations of 4-OH-CB107 and decreased scores on the Mental Development Index of the Bayley Scales of Infant Development in children aged 16 months in a Slovakian cohort [21]. In a Dutch cohort, prenatal exposure to higher 4-OH-CB107 levels was associated with reduced motor function [23] and sex-specific reductions in neurological functioning in three-month-old infants (less optimal functioning was seen in males) [24]. In both studies, the detected mean of 4-OH-CB107 concentration in maternal sera was lower than the levels detected in our study (0.037 ng/g wet weight [21] and 0.067 ng/g wet weight [23]).…”

“…OH-PCBs can cross the placenta [14–17], and OH-PCB levels in maternal plasma are highly correlated with levels in umbilical cord plasma [17–20]. Prenatal exposure to OH-PCBs, primarily to 4-OH-CB107, has been related to unfavorable neurodevelopment [21–24]; however, only one study has reported on the relationship between OH-PCBs and newborn anthropometrics [25]. That study, which found no associations, is based on a sample size of 79 maternal-newborn pairs.…”