Dietary Intake Contributed the Most to Chlorinated Paraffin Body Burden in a Norwegian Cohort

Abstract

Determining the major human exposure pathways is a prerequisite for the development of effective management strategies for environmental pollutants such as chlorinated paraffins (CPs). As a first step, the internal and external exposure to CPs were quantified for a well-defined human cohort. CPs in participants' plasma and diet samples were analyzed in the present study, and previous results on paired air, dust, and hand wipe samples were used for the total exposure assessment. Both one compartment pharmacokinetic modeling and forensic fingerprinting indicate that dietary intake contributed the most to body burden of CPs in this cohort, contributing a median of 60−88% of the total daily intakes. The contribution from dust ingestion and dermal exposure was greater for the intake of long-chain CPs (LCCPs) than short-chain CPs (SCCPs), while the contribution from inhalation was greater for the intake of SCCPs than medium-chain CPs (MCCPs) and LCCPs. Significantly higher concentrations of SCCPs and MCCPs were observed in diets containing butter and eggs, respectively (p < 0.05). Additionally, other exposure sources were correlated to plasma levels of CPs, including residence construction parameters such as the construction year (p < 0.05). This human exposure to CPs is not a local case. From a global perspective, there are major knowledge gaps in biomonitoring and exposure data for CPs from regions other than China and European countries.

Biomonitoring, exposure routes and risk assessment of chlorinated paraffins in humans: a mini-review

“…A recent published study identified that dietary intake was the most predominant source of daily CP intake, contributing up to 88%, 82% and 60% of the total SCCP, MCCP and LCCP intake, based on a Norwegian cohort using one compartment pharmacokinetic modeling and forensic fingerprinting. 28 CPs were ubiquitously detected in various foodstuffs and considered accumulated in animal-sourced foods due to the high lipophilicity and persistence of CPs. 1,26,67 The calculation equation for the EDI of CPs via dietary intake was listed in ESI Table S2 † 34,65.…”

“…Dermal contact of CPs was proved by the identification of CPs in dust samples from resident living rooms, offices, sports courts and shopping malls, 29,65,74,75 and more direct evidence includes hand wipe samples and silicone wristbands. 28,32 It has been reported that dermal intake can contribute up to 14% of the total MCCP and 29% of the total LCCP intake. 28 The calculation equation for the EDI via dermal absorption of CPs is listed in ESI Table S2 † 1,32,78.…”

“…Their global production increased rapidly and had exceeded the total historically produced polychlorinated biphenyls (PCBs), resulting in a ubiquitous existence in environmental samples, biota and humans. 28 During the last few decades, CP contamination and potential adverse health effects have received increasing attention.…”

“…Furthermore, although dietary intake was the predominant CP exposure route, other exposure routes such as inhalation, dust ingestion and dermal exposure might be underestimated, particularly for MCCPs and LCCPs, which had higher proportions of total intake from dust ingestion and dermal exposure. 28 The lack of appropriate analytical techniques for vSCCPs and LCCPs may produce extra uncertainties in the estimates of exposure and body burdens of total CPs. The biomonitoring of MCCPs and LCCPs was still scarce and the toxicological data are lacking.…”

“…Meanwhile, humans are unavoidably exposed to environmental CPs through dietary intake, [26][27][28] inhalation, 29,30 dust ingestion 29,31 and dermal contact. 28,32 The tolerable daily intake (TDI) of SCCPs was 11 mg per kg body weight (bw) per day according to the World Health Organization and the International Programme on Chemical Safety 1996 (WHO/IPCS). The TDI of MCCPs was 4 mg per kg bw per day according to the UK Commitee on Toxicology.…”