[en] Highlights: • SCCPs and MCCPs were tested in 62 pairs of human hair and nails from North China. • CP concentrations in hair were significantly higher than those in nails. • The homologue profiles of CPs in hair were similar to those in nails. • The CP levels positively correlated with age for hair, whereas negative linear correlations were observed in nails. • Age and the MCCPs/SCCPs ratios might influence the accumulation of CPs in hair and nails. Most of the studies on short- and medium-chain chlorinated paraffins (SCCPs and MCCPs) in human tissues have focused on human milk and blood. However, little is known about the occurrence of CPs in human hair and nails. In this study, SCCPs and MCCPs were analyzed in 62 pairs of human hair and nails from North China. Median concentrations (range) of SCCPs and MCCPs in human hair were 239 (19.2–877) and 325 (16.9–893) ng/g dw, respectively, all of which were significantly higher than 154 (57.7–355) and 233 (61.0–476) ng/g dw, respectively, in nail samples (p < 0.05). The homologue profiles of CPs in human hair were similar to those in nails, where SCCPs and MCCPs were dominated by C₁₀Cl_6–7 and C₁₄Cl_7–8, respectively. A significant positive relationship was observed between CP levels and age of people for hair, whereas negative linear correlations were observed for nails. The redundancy analysis indicated that age of people might be the main influencing factor on the accumulation of CPs in hair and nails. The present study performed comprehensive evaluation of CP exposure levels in human hair and nail and highlights the need for more data on relationship between internal and external exposure to CPs.

[en] Highlights: • High-molecular-weight phthalate diesters prevail in e-waste dust. • Phthalate alternatives and phthalate monoesters prevail in e-waste dust as well. • Biodegradation of diesters was recognized as the main source of monoesters in dust. • Phthalates and phthalate alternatives are being simultaneously used in e-products. • Occupational workers suffer from serious combined exposure to phthalate chemicals. This study first discovered the prevalence of phthalate (PAE) alternatives and PAE monoesters alongside traditional PAEs with elevated concentrations in indoor dust from typical e-waste recycling industrial park and adjacent communities. Among nine PAEs, high-molecular-weight (HMW) PAEs dominated over low-molecular-weight (LMW) PAEs in e-waste dust, with total concentrations (∑₉PAEs) ranging from 170 to 5300 μg g⁻¹. The diisononyl phthalate (DiNP) was identified as the most abundant PAE in e-waste dust, with over 10 times higher median concentration than that measured in home dust. Total concentrations of three PAE alternatives ranged from 20 to 1600 μg g⁻¹ in e-waste dust, which were 3–10 times higher than the measured levels in home dust. A total of 13 monoesters were all identified in all samples with total concentrations of 4.7–59 μg g⁻¹, and biodegradation of diesters was recognized as the major source of monoesters present in indoor dust. Significant correlations between the concentrations of PAE alternatives and the HMW PAEs were observed (p < 0.05), indicating that they are being simultaneously used in electronic and electrical products. The occupationally high co-exposure of e-waste dismantling workers to multiple PAEs and PAE alternatives as well as their monoesters should be of concern.

[en] Highlights: • SCCPs were detected in all alpine fish samples collected from the Tibetan Plateau. • Altitude-dependent accumulation of SCCPs in alpine fish was first found. • Shorter congener groups have higher transport abilities to higher altitudes. • SCCPs in alpine fish were mainly sourced from the long-range atmospheric transport. • Altitude-dependent of SCCPs was mainly due to the mountain cold-trapping effects. -- Abstract: High mountain cold-trapping effects can play important roles in the global long-range transport of persistent organic pollutants (POPs). Short chain chlorinated paraffins (SCCPs) have recently been included into the Stockholm Convention as a new class of POPs. However, the long-range transport behavior and environmental fate of SCCPs still remain largely unknown in high-altitude mountain areas. In this study, a total of 51 fish samples were collected from five high-altitude mountain lakes and Lasha river across the Tibetan Plateau. SCCPs were positively detected in all fish samples, and the concentrations ranged from 3.9 to 107 ng g⁻¹ dry weight (dw) with an average of 26.6 ng g⁻¹ dw. Compared to aquatic organisms from the Artic and Antarctica, the SCCP levels found in alpine fish from the Tibetan Plateau were lower. A significant increasing trend in accumulation levels of SCCPs in alpine fish with the increasing altitude was found on the Tibetan Plateau (r = 0.98, p < 0.001). Shorter chain congener group C10 showed a significant increase in percentage contribution to total SCCPs with increasing altitude, but a contrary tendency was found for longer chain congener group C13. The widespread occurrence of SCCPs in Tibetan fish was mainly sourced from the long-range atmospheric transport, and the altitude-dependent distribution of SCCPs was due to the mountain cold-trapping effects and potential susceptibility to bioaccumulation. To our knowledge, this is the first report regarding the altitude-dependent accumulation of SCCPs in biota in the polar environment.

[en] Currently known immunoassays for aflatoxins (AFs) usually are not capable of simultaneous determination of total AFs (i.e., aflatoxin B_1, aflatoxin B_2, aflatoxin G_1, aflatoxin G_2) due to the lack of group-specific antibodies. We are presenting here a colorimetric method for determination of total AFs by exploiting the Hg(II) ion-mediated aggregation of lysine-functionalized gold nanoparticles (Lys-AuNPs). AFs bind Hg(II) ion to form stable complexes, and this prevents the Hg(II) induced aggregation of Lys-AuNPs. Hence, the color change of solutions of AuNPs that occurs after aggregation of the AuNPs is suppressed. This effect was exploited to design a method for quantitation of AFs that can be detected by UV-Vis spectrophotometry (by measuring the ratio of absorbances at 725 nm and 525 nm), and even with bare eyes. The method has a very low detection limit (1.1 ppb) and is highly selective for AFs over other mycotoxins. Colorimetric analysis of rice samples by this method gave results that were in good agreement with those obtained by HPLC. To the best of our knowledge, this is the first method for visual detection of total AFs based on the distance-dependent optical properties of AuNPs. (author)