PCB exposure and cochlear function at age 6 years

Abstract

Epidemiological studies have documented adverse associations between exposure to polychlorinated biphenyls (PCBs) and otological outcomes. Previously, we documented decreased distortion product otoacoustic emission (DPOAE) levels in children exposed to PCBs, up to the age of 45 months, amongst a cohort of children in eastern Slovakia. The objective of the present study is to evaluate cochlear dysfunction at 72 months of age in 214 children from this same cohort and to compare the otoacoustic test sensitivity to that of pure tone audiometry (PTA). The association between DPOAE, PTA, and PCBs was estimated by means of multivariate ANOVA (MANOVA) and linear regression models. ROC curves were computed to estimate the DPOAE-test power in children. The DPOAE level at 72 months was related to PCB-153 serum levels. The DPOAE Input/Output function test at mid-frequency (2 kHz) has shown instead nonmonotonic dependence on PCB exposure, for the left ears of children, over the whole growth curve. No significant association was found between PTA hearing levels and PCB-153 concentration. High diagnostic power of the DPOAE-test was found in children, similar to that found by the same authors in adults. In conclusions the DPOAE-PCB correlation obtained at 72 months is similar to that at 45 months suggesting a permanent and stable ototoxic effect of the PCB exposure. The lack of statistical significance of the PCB-PTA correlation suggests that DPOAEs are sensitive biomarkers of cochlear damage.

Developmental exposure to polychlorinated biphenyls prevents recovery from noise-induced hearing loss and disrupts the functional organization of the inferior colliculus

“…Environment Protection Agency (Ross, 2004) but are highly chemically stable, which has led to widespread and persistent environmental contamination (Beyer and Biziuk, 2009). Given that PCBs can enter the placenta and breast milk (Jacobson et al, 1984), they also pose a developmental threat (Guo et al, 2004) including to the cochlea (Uziel, 1986; Goldey et al, 1995; Wong et al, 1997; Knipper et al, 2000; Song et al, 2008) and developmental exposure to PCBs impairs the hearing of humans and animals (Goldey et al, 1995; Herr et al, 1996; Crofton and Rice, 1999; Crofton et al, 2000; Lasky et al, 2002; Powers et al, 2006; Kenet et al, 2007; Powers et al, 2009; Jusko et al, 2014; Min et al, 2014; Palkovičová Murínová et al, 2016; Sadowski et al, 2016; Lee et al, 2021). Given the high population prevalence of dual exposure to PCBs and noise, the objective of the current study was to examine the interaction between developmental exposure to PCBs and NIHL later in adulthood in both the peripheral and central auditory systems.…”