High-Throughput Determination and Characterization of Short-, Medium-, and Long-Chain Chlorinated Paraffins in Human Blood

Abstract

The industrial chlorinated paraffins (CPs) are comprised of short-chain (SCCPs), medium chain (MCCPs), and long chain (LCCPs) CPs. Although SCCPs and MCCPs are environmentally ubiquitous, little is known about CPs in humans. This study established a method for simultaneous determination of 261 SCCP, MCCP, and LCCP congener groups in one injection by reversed ultrahigh-pressure liquid chromatography coupled with chlorine-enhanced electron spray ionization-quadrupole time-of-flight mass spectrometry. The method yielded good peak shapes, high sensitivities, and low coeluted interferences for all examined CPs. LCCPs with carbon numbers of 21 to 27 were detected in their standard technical mixtures, and MCCPs and LCCPs impurities were detected in the LCCP and MCCP standard technical mixtures, respectively, causing quantification deviations when these mixtures were used for calibration. After considering these impurities' contribution to the total concentrations, the quantification accuracies for ∑SCCPs, ∑MCCPs, and ∑LCCPs ranged from 95.1 ± 8.4% to 105.6 ± 9.2% in the eight CP technical mixtures. The method was successfully applied to determine CPs in about 6 g human blood samples from a general population, and estimated ∑SCCP, ∑MCCP, and ∑LCCP concentrations to be 370-35 000, 130-3200, and 22-530 ng/g lipid weight (n = 50), respectively. A comparison of blood and soil/air CP profiles from the same areas suggested a relatively higher potential for the accumulation of SCCPs, compared with MCCPs, in humans.

Environmental Risks of Medium-Chain Chlorinated Paraffins (MCCPs): A Review

“…9). MCCP concentrations measured in human placenta are slightly higher, MCCP concentrations measured in human blood 76 are around one order of magnitude higher than the measured MCCP concentrations in human breast milk. Studies on adverse effects of MCCPs in humans are missing, so it is currently impossible to assess the risk of MCCPs to humans.…”

Chlorinated Paraffins in Car Tires Recycled to Rubber Granulates and Playground Tiles

“…LCCPs up to C 23 were also detected in human blood (up to 530 ng/g LW) from China. 14 These results indicate that LCCPs have a bioaccumulative potential, which highlights the importance of including LCCPs in the measurement of CPs.…”

“…Based on the relatively limited toxicity data available for LCCPs, they seem to be less toxic to organisms compared to SCCPs and MCCPs. 13 LCCPs have recently been detected in human blood (up to 530 ng/g lipid weight) 14 from China and in wildlife samples from China and Sweden with levels up to 10 μg/g lipid weight, whereby in one of the biota samples from Sweden LCCPs were dominant. 15,16 These findings may highlight the importance to include LCCPs in measurement programs for CPs.…”

Complex Mixtures of Chlorinated Paraffins Found in Hand Wipes of a Norwegian Cohort

“… 22 All CPs are persistent, 23 and they are bioaccumulative in humans. 24 , 25 Mammalian toxicity research has mostly focused on SCCPs 26 and has identified SCCPs as possible carcinogens to humans. 27 Although the toxicity of MCCPs and LCCPs has been studied less, MCCPs are considered to meet the REACH toxicity criteria, 28 and MCCP exposure has been shown to cause hemorrhaging effects in rats.…”