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Occupational exposure to trichloroethylene (TCE) has been associated with alterations in B-cell activation factors and an increased risk of non-Hodgkin's lymphoma (NHL). Here, we aimed to examine the biological processes influenced by trichloroethylene (TCE) exposure to understand the underlying molecular mechanisms. This cross-sectional molecular epidemiology study included data of 1317 targeted proteins in the serum from 42 TCE exposed and 34 unexposed factory workers in Guangdong, China. We used multivariable linear regressions to identify proteins associated with TCE exposure and examined their exposure-response relationship across categories of TCE exposure (unexposed, low exposed:10 ppm, high exposed: ≥10 ppm). We further examined pathway enrichment of TCE-related proteins to understand their biological response. Occupational exposure to TCE was associated with lower levels of tumor necrosis factor receptor superfamily member 17 (TNFRSF17; β = -0.08; p-value=0.0003) and Kynureninase (KYNU; β = -0.10, p-value = 0.002). These proteins also showed a significant exposure-response relation across the unexposed, low exposed, and high exposed workers (all p-trends0.001, FDR0.20). Pathway analysis of TCE-related proteins showed significant enrichment (FDR0.05) for several inflammatory and immune pathways. TCE exposure was associated with TNFRSF17, a key B-cell maturation antigen that mediates B-cell survival and KYNU, an enzyme that plays a role in T-cell mediated immune response. Given that altered immunity is an established risk factor for NHL, our findings support the biological plausibility of linking TCE exposure with NHL. This article is protected by copyright. All rights reserved.

ObjectivesThere has been concern over the possible risk of autoimmune diseases from exposure to trichloroethylene (TCE), an industrial solvent and common pollutant near hazardous waste sites. Studies of TCE-exposed lupus-prone mouse strains have reported increases in serum antinuclear antibodies (ANAs), a marker of autoimmunity, and autoimmune pathologic changes, while epidemiologic studies have provided limited support for an association between TCE exposure and scleroderma. To investigate exposure-related biologic evidence of autoimmunity in humans, we measured ANA levels in sera from a cross-sectional study of TCE-exposed (n=80) and TCE-unexposed (n=96) workers in Guangdong, China.MethodsFull-shift personal air exposure measurements for TCE were taken prior to blood collection. Serum ANAs were detected by immunofluorescence on HEp-2 cells. We calculated ORs and 95% CI relating levels of TCE exposure (categorised using tertiles as cut-points) and ANA positivity (1+ intensity at 1:320 dilution) using multivariable logistic regression.ResultsSamples from 16 of 176 participants were ANA-positive. We found higher levels of TCE exposure (concentrations>17.27 ppm) to be associated with an elevated odds of ANA positivity (OR 4.7, 95% CI 1.3 to 16.8) compared with unexposed controls. This association remained after excluding two subjects with diagnosed autoimmune disease (OR 4.5, 95% CI 1.2 to 16.2). We did not observe an association with ANAs at lower exposure levels.ConclusionsOur findings, to our knowledge the first direct human evidence of an association between TCE exposure and systemic autoimmunity, provide biologic plausibility to epidemiologic evidence relating TCE and autoimmune disease.

The construction of Z-scheme system is a promising approach for photocatalytic hydrogen evolution (PHE). In this study, we fabricated a direct Z-scheme system consisting of defect-rich g-C3N4 nanosheets (DR-CNNS) crumpled nanosheets with defect-rich TiO2 (DR-TiO2) nanoparticles via a dual defective strategy. The optimized dual-defective rich TiO2/CNNS composite showed a superior PHE rate of ˜651.79 μmol/h with a turnover frequency of ˜419.3 h−1 as well as high stability and recyclability, which presented the highest value in single defective TiO2 or g-C3N4-based photocatalysts families reported previously. Furthermore, this protocol could also be extended to synthesize other dual defective g-C3N4/oxides (ZnO, SnO2, etc.) heterostructures. The improved photocatalytic performances could be ascribed to the following aspects: (1) rich dual defect, narrowing the band gap and providing more reactive sites for PHE; (2) intimate interface, facilitating interfacial migration and utilization of photogenerated charges; (3) Z-scheme structure, accelerating photogenerated electron-hole pair separation and thus leading to more efficient PHE. Our work highlights the critical role of defects in construction of Z-scheme system and provides the possibility of utilizing dual defective g-C3N4-based systems for other photocatalytic applications including CO2 reduction and water purification.