Toxicology and Industrial Health最新文献

Perfluorooctane sulfonate (PFOS) is a synthetic persistent organic compound that is widely used in industrial products. Studies have shown that PFOS can accumulate in environment and pose a threat to human health. As the kidney is the main excretory organ for PFOS, it is important to study PFOS damage to the kidney to investigate its toxicity. Human proximal tubular epithelial cells (HK-2) were treated with 200 μM PFOS or 1 μM Fer-1. Cell viability, the levels of MDA, GSH, intracellular iron ion, and GPX-4 were determined. The expression of KIM-1 and endoplasmic reticulum stress (ERS) related proteins were determined. The expression levels of KIM-1, a marker of renal tubular injury, and ERS-related proteins, GRP78, ATF6, IRE1, and PERK, were significantly increased in HK-2 cells exposed to PFOS. The levels of MDA and intracellular total iron ion also were significantly increased in HK-2 cells exposed to PFOS and the levels of GSH and GPX-4 were significantly decreased. PFOS can damage HK-2 cells through ferroptosis and endoplasmic reticulum stress, which provides a theoretical foundation for exploring the toxicity of PFOS to the kidney.

Trichloroethylene (TCE) is a volatile, colorless liquid that is widely used as a chlorinated organic vehicle in industrial production and processing industries. Many workers exposed to trichloroethylene may develop trichloroethylene hypersensitivity syndrome (THS). However, the underlying mechanism of THS is still unclear, especially liver injury. The present study aimed to investigate whether Wnt5a/c-Jun N-terminal kinase (JNK) is involved in and regulates liver injury caused by TCE exposure and to provide new directions for the prevention and treatment in clinical settings of liver injury caused by TCE exposure. We used 6- to 8-week-old SPF-grade BALB/c female mice to establish a TCE sensitization model and explored the mechanism through inhibitor intervention. We found that the expression of Wnt5a/JNK was significantly elevated in the liver of TCE sensitization-positive mice. Inhibitors of Wnt Production 2 (IWP-2) are known antagonists of the Wnt pathway. TCE-sensitization mice treated with IWP-2 showed downregulated Wnt5a/JNK expression, reduced Kupffer cell activation, and decreased liver injury. At the same time, we found that phosphorylated JNK in TCE-sensitization mouse livers and extracted Kupffer cells showed a significant downward trend after inhibition of Wnt5a function. We also found that a specific JNK inhibitor, SP600125, decreased the secretion of cytokines and chemokines and decreased Kupffer cell activation. We demonstrated that Wnt5a/JNK was involved in the regulation of liver injury in TCE-sensitization mice and that it exacerbated liver injury by activating Kupffer cells and releasing chemokines. We therefore hypothesized that Kupffer cell activation was affected by JNK, which reduced chemokine and cytokine secretion and attenuated liver injury in TCE-sensitization mice.

Silica nanoparticles (SiNPs) are widely utilized in occupational settings where they can cause lung damage through inhalation. The objective of this research was to explore the metabolic markers of SiNPs-induced toxicity on A549 cells by metabolomics and provide a foundation for studying nanoparticle-induced lung toxicity. Metabolomics analysis was employed to analyze the metabolites of SiNPs-treated A549 cells. LASSO regression was applied for selection, and protective measure experiments were conducted to validate the efficacy of selected potential toxicity mitigators. After SiNPs treatment, 23 differential metabolites were identified, including lipids, nucleotides, and organic oxidants. Pathway analysis revealed involvement in various biological processes. LASSO regression further identified six metabolites significantly associated with SiNPs toxicity. Notably, phosphatidylethanolamine (PE (14:1(9Z)/14:0)) showed enrichment in six significant metabolic pathways and with an AUC of 1 in the ROC curve. Protective measure experiments verified its protective effect on A549 cells and demonstrated its considerable inhibition of SiNPs-induced cytotoxicity. This study elucidated SiNPs-induced cytotoxicity on A549 cells and identified PE as a potential toxicity mitigator. These findings contribute to understanding the mechanisms of nanoparticle-induced lung toxicity and inform occupational health preventive strategies.

At present, the reproductive toxicology of neonicotinoids has received greater attention, however, its potential mechanisms are still not fully understood. Acetamiprid (ACE) is a new-generation neonicotinoid and has become a ubiquitous contaminant in the environment. This study aimed to investigate the toxic effects of ACE in TM3 Leydig cells based on transcriptome analysis. The viability and apoptosis of TM3 cells exposed to different concentrations of ACE were assessed by CCK8 and flow cytometry, respectively. After ACE exposure, transcriptome analysis was performed to screen differential expression genes (DEGs), followed by qPCR verification. Results showed that ACE exposure resulted in a time- and dose-dependent decrease in the viability of TM3 cells (p < .05). ACE also exerted a dose-dependent pro-apoptotic effect on TM3 cells. Results of RNA-seq showed that 1477 DEGs were obtained, of which 539 DEGs were up-regulated and 938 DEGs were down-regulated. GO and KEGG analyses of DEGs showed that DNA replication and cell cycle might be the key mechanisms for the cytotoxicity of ACE. qPCR results demonstrated that Mdm2, Cdkn1a (p21) and Gadd45 were significantly increased, and Pcna, Ccna2 (CycA), Ccnb1 (CycB), Ccne1 (CycE), and Cdk1 were significantly decreased, indicating that ACE exposure might promote G1/S and G2/M cell cycle arrest. Additionally, FoxO, p53, and HIF-1 signaling pathways and ferroptosis might play important roles in ACE-induced reproductive toxicity. Collectively, this study provides new perspectives into the mechanism of ACE-induced reproductive toxicity and lays a theoretical foundation for the in-depth study of non-target toxicity mechanisms of neonicotinoid insecticides.

Di(2-ethylhexyl) phthalate (DEHP), a widely utilized plasticizer in various consumer products, is classified as an endocrine disruptor and has been implicated in numerous adverse health effects, including oxidative stress, inflammation, and metabolic disturbances. Despite the growing body of literature addressing the systemic effects of DEHP, the specific influence of DEHP-induced oxidative stress on mitochondrial function within detoxification organs, particularly the liver and kidneys, remains largely unexplored. This study evaluated the effects of DEHP exposure (0, 100, 200, and 400 mg/kg/day) on mitochondrial oxidative stress, trace elements, and mineral metabolism associated with signaling pathways in the liver and kidneys of rats. Altered mitochondrial oxidative stress status was indicated by impaired glucose 6-phosphate dehydrogenase (G6PD), 6-phosphoglucerate dehydrogenase (6-PGD), glutathione reductase (GR), glutathione s-transferase (GST), and glutathione peroxidase (GPx) activities, along with significant disruptions in essential minerals and trace elements, including Na, Mg, Cu, Zn, and Fe. Key oxidative stress signaling pathways, such as NF-κB, Akt, STAT3, and CREB, glucose, and tissue homeostasis, displayed dose-dependent responses to DEHP, indicating complex regulatory mechanisms. This study represents the first comprehensive investigation into DEHP-induced mitochondrial dysfunction, highlighting its effects on oxidative stress metabolism, trace element homeostasis, and cellular signaling pathways in detoxification organs. These findings provide novel insights into the mitochondrial mechanisms underlying DEHP toxicity and underscores the need for further research into the implications of plasticizer exposure on human health.

(E)-1,1,1,2,2,5,5,6,6,6-Decafluoro-3-hexene (HFO-153-10mczz-E) (CASRN 1256353-26-0) is a volatile liquid proposed for use as a new low global-warming potential dielectric fluid in cooling applications. Workplace exposures are expected to be by inhalation exposure. The substance has low acute inhalation toxicity as indicated by a 4-h inhalation LC₅₀ value of approximately 8000 ppm. A suite of in vitro assays was negative for skin and eye irritation as well as for skin sensitization potential. The chemical did not induce cardiac sensitization up to 5000 ppm. Repeated inhalation exposure in rats for 4 or 13 weeks did not produce any effects attributable to the substance at 3000 ppm, the maximum tested concentration. No indications of developmental or reproductive toxicity were observed in studies in rats, also conducted with a maximum concentration of 3000 ppm. There was no indication of genotoxicity in the Ames assay, an assay with human TK cells, chromosome aberration in cultured human lymphocytes, or an in vivo rat micronucleus assay. The critical study for the development of the 8-hour TWA WEEL is the 13-week inhalation toxicity study with a NOAEC of 3000 ppm (32,400) mg/m³). This inhalation NOAEC was adjusted by application of appropriate uncertainty factors to account for interindividual variability, subchronic to chronic exposure extrapolation and other sources of uncertainty. A WEEL value of 200 ppm (2160 mg/m³) is expected to provide an acceptable margin of safety for potential adverse health effects in workers.

Citreoviridin (CIT) is a mycotoxin produced by various fungi. Although CIT has been reported to cause neurotoxicity, the molecular mechanism is poorly understood. Therefore, the aim of this study was to investigate the effects and molecular mechanisms of CIT in neurotoxicity. Different concentrations of CIT were treated to rat pheochromocytoma (PC-12 cells), and oxidative stress parameters, cytokine levels, and cell apoptosis were evaluated. CIT treatment (5 and 10 μM) significantly induced PC-12 cell apoptosis and increased lactate dehydrogenase activity. Additionally, CIT treatment induced oxidative stress, as evidenced by a significant increase in intracellular levels of reactive oxygen species, malondialdehyde, and superoxide dismutase and a decrease in glutathione activity. Moreover, CIT treatment induced an inflammatory response, as evidenced by a significant increase in the intracellular levels of the proinflammatory cytokines tumor necrosis factor-alpha and interleukin-1-beta in PC-12 cells. Furthermore, quantitative PCR and western blotting showed that CIT treatment increased both the protein and mRNA expression of GADD45α and p21 in PC-12 cells, suggesting that CIT may induce apoptosis by inhibiting cell cycle, blocking cell growth, and damaging DNA. Conclusively, this study contributes the understanding the toxicity mechanisms of CIT to nerve cells.

Occupational exposure limits (OELs) and occupational exposure bands (OEBs) provide quantitative benchmarks for worker health protection. If empirical toxicology data are insufficient to derive an OEL, an OEB is often assigned using partial toxicology data along with other relevant hazard information. There is no consensus methodology to assign OEBs for chemicals lacking any empirical toxicology data. Thus, this study developed an in silico framework for OEB assignment of data poor compounds. It relies upon computational tools to evaluate standard toxicological end points and to assign reliability ratings, which are then used to assign Global Harmonization System (GHS) hazard categories. Subsequently, the hazard categories are entered into the National Institute for Occupational Safety and Health (NIOSH) occupational exposure banding tool to assign bands for individual end points as well as an overall OEB. As a proof-of-concept, five compounds with established OELs (i.e., "knowns") were evaluated. The knowns were assigned to overall OEBs C, D, or E, four of which were equal to or lower than the OEBs based on actual harmonized GHS categories as well as established OELs, indicating that the OEBs assigned using this framework are likely to be protective. Subsequently, five compounds with little to no experimental data and no established OELs from any U.S. agency or consensus OEL-setting organizations were evaluated (i.e., "unknowns"). The unknowns were assigned to overall OEBs D or E. It was concluded that the proposed framework can be used to assign protective OEBs to compounds with little to no toxicology testing data. As additional data become available, the compound may be de-risked, and a precautionary OEB (or an OEL) can be assigned. The proposed framework provides an example of a practical methodology to evaluate data poor compounds and shows that the output of this framework is expected to be protective of worker health.

Research has shown that exposure to bisphenol A (BPA), a widely used plasticizer, can lead to meiotic errors, resulting in poor reproductive cell quality and infertility. Health-related concerns have prompted the search for BPA alternatives; however, evidence suggests that currently used BPA analogs, such as bisphenol S (BPS), may pose similar risks to human health. While the effects of BPA on female fertility are well documented, the impact of BPA exposure on sperm quality is poorly understood. To better understand the effects of bisphenol analogs on spermatogenesis, we synthesized a less investigated BPA analog, tetramethyl bisphenol F (TMBPF), and compared its reprotoxic potential to that of widely used BPA and BPS using C. elegans-based assays. We evaluated germ cell count, spermatid size, morphology, and activation in males treated with 0.5 mM ethanol-dissolved bisphenol analogs for 48 h as well as their cross-progeny number and viability. Our results indicated that all of the evaluated bisphenol analogs-BPA, BPS, and TMBPF-adversely affect male fertility to varying degrees. Whereas all three bisphenols reduced spermatid size, only BPA exposure resulted in impaired spermatid activation and significantly reduced brood size. In addition, a decrease in embryonic viability, suggestive of an increased incidence of sperm chromosomal aberrations, was observed following exposure to all of the tested bisphenols. Further investigation is necessary to fully elucidate the underlying mechanisms and implications of BPA, BPS, and TMBPF on spermatogenesis.

Mesothelioma is a fatal disease that has historically been associated with exposure to airborne asbestos. Because occupational asbestos exposures dropped dramatically in the late 1960s and early 1970s, far fewer cases of mesothelioma today are due to these fibers but, instead, are usually a result of the aging process or genetic predisposition. In May of 2022, a Morbidity and Mortality Weekly Report (MMWR) was issued by the Centers for Disease Control and Prevention (CDC) regarding malignant mesothelioma incidence in women from 1999 to 2020. While this MMWR alerted citizens to the continued presence of the disease, after reading this article one might have thought that the CDC was suggesting that the disease was increasing in women due to asbestos exposures (which it is not). In the present analysis, we investigate several factors related to the interpretation of epidemiological data for mesothelioma, including the role of asbestos as a risk factor over time. The authors conducted a review of the scientific community's understanding of mesothelioma incidence and asbestos exposures amongst women, as well as an investigation of the methods and references in the MMWR article. Although various articles have recently discussed the incidence of both peritoneal and pleural mesothelioma in women, it is fortunate that the age-adjusted rates for mesothelioma have remained flat (neither increased nor decreased significantly) in women for the past 50 years. Incredibly few women in the U. S. have had appreciable cumulative exposures to any type of asbestos (chrysotile, amosite, or crocidolite) in the workplace or from the ambient environment, especially since about 1965-1970. In this paper, we highlight six factors that should be considered when evaluating the incidence of mesothelioma amongst American women in the current era. Without sufficient consideration of these factors, improper conclusions have been drawn over the past several years.