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Nitrogenous flame retardants (NFRs) have aroused worldwide public concern as their nephrotoxic effect. However, knowledge regarding the pathogenesis mechanism of their exposure to induce kidney injury remains largely unknown. In this study, eight NFRs, four oxidative stress biomarkers (OSBs), and one kidney injury biomarker, namely neutrophil gelatinase-associated lipocalin (NGAL), were measured in urine specimens collected from residents living around e-waste disassembly and reference areas, representing two exposure scenarios. Significant higher concentrations of Σ

Microplastics (MPs) are a contaminant of increasing concern in the environment. However, the impacts of MPs on soil ecosystems and biogeochemical processes like nitrogen cycle have not been well elucidated. In this study, we designed an indoor microcosm experiment to investigate the effects of exposure to low density polyethylene (LDPE) MPs on soil bacterial community and nitrogen cycling function over a 90-day incubation. Next-generation sequencing of the 16S rRNA genes revealed that both 2% and 7% LDPE MPs exposure slightly affected the soil bacterial diversity. Further analysis at the genus level showed differential tolerance to LDPE MPs, the genera Pedomicrobium, Steroidobacter, Pseudonocardia, Nitrospira and Turicibacter were enriched in the soil with 2% (w/w) LDPE MPs amendment, while the genera Pedomicrobium, Mycobacterium and Hyphomicrobium were significantly enriched in the soil with 7% (w/w) LDPE MPs amendment on days 15 and 30. Co-occurrence network analysis further suggested that LDPE MPs changed bacterial network complexity and modularity and Acidobacteria formed intimate associations with each other in responding to LDPE MPs exposure. Additionally, LDPE MPs in soil increased the abundance of nifH, AOBamoA and nirK genes involved in nitrogen cycling in different incubation phases compared to the control. The abundance of AOAamoA genes decreased on day 15 and then increased. Conversely, the abundance of nirS genes increased during the first 15 days and then decreased. These results suggested that both 2% and 7% LDPE MPs impact soil bacterial network structure and alters functional groups involved in soil nitrogen cycling processing.

Concentrations of eight trace metals (TMs) in road dust (RD) (particles 25 μm) from urban areas of Xinxiang, China, were determined by inductively coupled plasma mass spectrometry. The geometric mean concentrations of Zn, Mn, Pb, As, Cu, Cr, Ni and Cd were 489, 350, 114, 101, 60.0, 39.7, 31.6, and 5.1 mg kg

The distribution of brominated flame retardants (BFRs) including ∑ 8 PBDEs, DBDPE, BTBPE, EH-TBB, BEH-TEBP and PBEB in road dust (RD) collected in Xinxiang, China was characterized. Analysis of RD samples indicated that the BFR abundance declined as traffic density decreased, with total mean levels of 292, 184, 163, 104 and 70 ng g −1 dust at sites from traffic intersections, main roads, collector streets, bypasses and parks, respectively. A possible explanation for this phenomenon is that the majority of BFRs may be emitted from the interior of vehicles via their ventilation systems. Of the 13 analyzed substances, BDE-209 and BEH-TEBP were the most abundant components in RD from Xinxiang. Similar amounts of ∑BDEs excluding BDE-209 were found at different types of sampling sites, and thus, atmospheric deposition is also a probable source of BFRs in RD which can be subject to air transportation. The main PBDE sources were traced to commercial products including DE-71, Bromkal 79-8DE, Saytex 201E and Bromkal 82 DE mixtures. Our results confirm that the use of deca-BDE commercial mixture is a major source of PBDE contamination in RD. Risk assessment indicated the concentrations of BFRs in RD in this study do not constitute a non-cancer or cancer risk to humans through ingestion. Annual emission fluxes of the commonly detected BFRs via RD in China were estimated to be up to 4980 kg year −1 .

To investigate the contamination level, distribution, possible source, and human exposure risk of polycyclic aromatic hydrocarbons (PAHs) in the urban traffic environment, 15 PAHs were measured in 34 road dust samples (particle size < 25 μm) collected from three grades of roads and park paths in Xinxiang, China. ΣPAHs concentrations ranged from 311 to 21200 ng g−1, with a mean of 5890 ng g−1 and decreased in the following order: main roads (7650 ng g−1) > collector streets (7410 ng g−1) > bypasses (2970 ng g−1) > park paths (1570 ng g−1), indicating that significant positive correlation existed between PAH contamination and traffic density. PAHs in all samples were dominantly composed of 4-ring PAHs, accounting for 44.8% of the total. Pyrene, fluoranthene, and chrysene were the predominant individual components and accounted for 14.7% (1.2–19.2%), 12.9% (3.3–20.3%), and 11.0% (2.5–18.6%) of ΣPAHs, respectively. The specific isomer ratios indicated that traffic emission was the dominant source of PAHs in road dust. The incremental lifetime cancer risk values showed that cancer risk from exposure to road dust–borne PAHs was acceptable for local residents in Xinxiang.

The health impact of haze is of great concern; however, few air quality studies have investigated trace pollutant contamination in the air. Size-segregated atmospheric particles (nine size fractions derived from PM10) were collected in dwelling (indoor) and traffic (outdoor) environments in Xinxiang, China, during light pollution conditions (air quality index (AQI), 60–90) and heavy pollution conditions (AQI, 350–550), and they were analysed for halogenated flame retardants (HFRs), including polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs) and Dechlorane Plus (DP) isomers. HFR occurrence levels generally decreased in the order of PBDEs > NBFRs > DPs. The total mean abundance ratios of heavy pollution/light pollution were 4.0, 2.9, 4.4 and 3.6 for PBDEs, NBFRs, DPs and HFRs, respectively. Meteorological conditions played distinctive roles in the HFR distribution in the air. Apparent differences were found for the particle size distribution of HFRs under light and heavy pollution conditions. In general, for adults, the estimated hazard quotient (HQ) and incremental lifetime cancer risk (ILCRBDE-209) values were approximately 1.7 × 10−2 and 9.3 × 10-9 in heavy pollution conditions, respectively, which were significantly higher than those in light pollution conditions (1.8 × 10-3 and 2.1 × 10-9, respectively).