Infant Exposure to PCBs and PBDEs Revealed by Hair and Human Milk Analysis: Evaluation of Hair as an Alternative Biomatrix

Abstract

Human hair, as an emerging biological monitoring matrix, has begun to be used in various human exposure studies, but little research has been done on persistent organic pollutants (POPs), especially for the body burden of POPs in infants. In this study, 36 breast-fed infants in Shanghai were recruited for a study to determine their exposure to POPs, including 12 dioxin-like polychlorinated biphenyls (dl-PCBs), 6 indicator PCBs, and 8 polybrominated diphenyl ethers (PBDEs) in the inner layer (internal) and outer layer (external) of infant hair and human milk. The similarity or difference of the POP distribution pattern or concentration among these matrices was investigated, and only weak correlations (r < 0.4) were observed between the POP concentration in human milk and infant hair (internal or external). POPs in human milk have a different profile than those in infant hair, while they have stable concentration ratios (0.58−2.72), similar distribution patterns, fine Spearman's rank correlations, and tangled principal component analysis (PCA) plots in each POP family between external and internal hair samples. The result suggested that POPs in internal hair can be easily affected by those in external hair, but POPs in human milk seem to have little contribution to the POP profile in internal hair. Although infant hair cannot reflect the POPs from diet or from body burden, it can be an ideal biomatrix that estimates infant exposure to POPs from exogenous sources like house dust when considering the similar pattern of POPs and their proper accumulation period in hair.

Gas and Liquid Chromatography Mass Spectrometry as a Tool for Elucidating Volatile Organic Compounds (VOCs) and Metabolites in Maternal Milk: A Perspective on Infants’ Health Risk Assessment

“…The matrices available for analyses include blood, urine, maternal milk, adipose tissue, hair and saliva [11][12][13]. Maternal milk as a biological monitoring matrix has great relevance for the potential risk to human health as it can be used more easily (collected via non-invasive techniques) among human tissues and fluids for biological monitoring in newborns, portraying also retrospective maternal exposure [14][15][16][17][18]. The comparatively high lipid content with respect to other biological fluids renders maternal milk a suitable matrix for lipophilic chemicals.…”

“…Since 1951, when 1,1,1-trichloro-2,2-bis(chlorodiphenyl)ethane (DDT) was the first environmental pollutant identified in human milk [19], this matrix's analysis has shown an interesting increase. At present, research on human milk analysis mainly focuses on persistent organic pollutants (POP) such as organochlorine pesticides (OCPs), polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) [14,16,20,21], while there is a relative lack of monitoring of their metabolites [11]. In 2018, Lehmann and colleagues compiled data on environmental chemicals in human milk in the United States and highlighted that these data are, indeed, mostly available for persistent, lipophilic chemicals in human milk [22].…”