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Toxicologic Pathology Feb 2013Hepatotoxicity is the most common organ injury due to occupational and environmental exposures to industrial chemicals. A wide range of liver pathologies ranging from... (Review)
Review
Hepatotoxicity is the most common organ injury due to occupational and environmental exposures to industrial chemicals. A wide range of liver pathologies ranging from necrosis to cancer have been observed following chemical exposures both in humans and in animal models. Toxicant-associated fatty liver disease (TAFLD) is a recently named form of liver injury pathologically similar to alcoholic liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD). Toxicant-associated steatohepatitis (TASH) is a more severe form of TAFLD characterized by hepatic steatosis, inflammatory infiltrate, and in some cases, fibrosis. While subjects with TASH have exposures to industrial chemicals, such as vinyl chloride, they do not have traditional risk factors for fatty liver such as significant alcohol consumption or obesity. Conventional biomarkers of hepatotoxicity including serum alanine aminotransferase activity may be normal in TASH, making screening problematic. This article examines selected chemical exposures associated with TAFLD in human subjects or animal models and concisely reviews the closely related NAFLD and ALD.
Topics: Animals; Biomarkers; Fatty Liver; Histocytochemistry; Humans; Occupational Diseases; Occupational Exposure; Risk Factors; Vinyl Chloride
PubMed: 23262638
DOI: 10.1177/0192623312468517 -
World Journal of Gastroenterology Sep 2019Portal hypertension, liver fibrosis, and angiosarcoma of the liver (ASL) have been reported among workers exposed to vinyl chloride monomer (VCM) since the 1970s. In... (Review)
Review
Portal hypertension, liver fibrosis, and angiosarcoma of the liver (ASL) have been reported among workers exposed to vinyl chloride monomer (VCM) since the 1970s. In 2007, the International Agency for Research on Cancer established the association of VCM with hepatocellular carcinoma (HCC), though only on the basis of the few cases available. Thereafter, recent reports from the United States cohort and a European sub-cohort of vinyl chloride workers provided compelling evidence of a strong association between cumulative VCM exposure and HCC risk. Further areas of research include the risk of liver cancer at lower levels of exposure and different patterns of risk of ASL and HCC with the time since exposure. The evidence of interaction between VCM exposure and other known liver carcinogens such as alcohol and chronic viral infection provides clues for the health surveillance of exposed workers. Notably, also the risk of VCM-associated chronic liver disease is modulated by alcohol consumption, viral infection, and genetic polymorphism. A counter-intuitive finding from cohort studies of exposed workers is the lower mortality from liver cirrhosis with respect to the general population; this can be attributed to the healthy worker effect and to the selection of liver cancer as the cause of death in the presence of concomitant chronic liver disease. Studies designed to overcome these intricacies confirmed an association between cumulative VCM exposure and the risk of liver cirrhosis.
Topics: Alcohol Drinking; Carcinogens; Cause of Death; Chronic Disease; Europe; Hemangiosarcoma; Humans; Hypertension, Portal; Liver Cirrhosis; Liver Neoplasms; Occupational Diseases; Occupational Exposure; Risk Factors; Survival Analysis; United States; Vinyl Chloride; Virus Diseases
PubMed: 31543680
DOI: 10.3748/wjg.v25.i33.4885 -
Journal of Hepatology Dec 2009Vinyl chloride monomer is a known cause of angiosarcoma of the liver. It also has other toxic effects on the liver, and it has recently been suggested that exposure to... (Review)
Review
Vinyl chloride monomer is a known cause of angiosarcoma of the liver. It also has other toxic effects on the liver, and it has recently been suggested that exposure to vinyl chloride also causes hepatocellular carcinoma. However, the data on which this conclusion is based is incomplete. There is inadequate ascertainment of unequivocal diagnoses. In the largest studies lack of data meant that confounding diseases such as viral hepatitis or alcoholic liver disease could not be assessed. At best, the increase in risk is minimal, based on more than 22,000 exposed workers and more than 640,000 person years of observation. However, based on the available data the hypothesis that vinyl chloride causes or contributes to the development of hepatocellular carcinoma remains unproven.
Topics: Animals; Carcinoma, Hepatocellular; Hemangiosarcoma; Humans; Liver; Liver Cirrhosis; Liver Neoplasms; Mutagens; Occupational Exposure; Risk Factors; Vinyl Chloride
PubMed: 19836850
DOI: 10.1016/j.jhep.2009.09.012 -
Journal of Clinical and Translational... Feb 2021The goal of this analysis was to evaluate the association between county-level ambient vinyl chloride (VC) and county-level liver cancer incidence and mortality rates in... (Review)
Review
The goal of this analysis was to evaluate the association between county-level ambient vinyl chloride (VC) and county-level liver cancer incidence and mortality rates in Texas. Modeled county-level ambient VC data were obtained from the National Air Toxics Assessment. Age-adjusted county-level liver cancer incidence rates were abstracted from the Texas Cancer Registry and age-standardized county-level liver cancer mortality rates were obtained from the peer-reviewed literature. Multivariable imputation was utilized to impute incidence rates in counties with suppressed liver cancer incidence rates. Negative binomial and Poisson regression models were utilized to evaluate the association between county-level ambient VC and county-level liver cancer incidence and mortality rates, respectively, adjusted for county-level heavy drinking prevalence, hepatitis mortality rates, median income, and race (percent Hispanic). County-level ambient VC was not associated with county-level liver cancer incidence or mortality rates. Specifically, when compared to the lowest tertile of ambient VC, the middle (relative risk [RR]: 1.06, 95% confidence interval [CI]: 0.95-1.19) and highest (RR: 1.03, 95% CI: 0.90-1.17) tertiles of ambient VC were not associated with liver cancer incidence. Similarly, county-level ambient VC in the middle (RR: 0.95, 95% CI: 0.85-1.05) and highest (RR: 0.93, 95% CI: 0.82-1.05) tertiles were not associated with liver cancer mortality. This analysis suggests that county-level ambient VC is not associated with liver cancer incidence or mortality in Texas. Our study provides novel results regarding liver cancer risk from low-level non-occupational exposure to ambient VC.
PubMed: 33604260
DOI: 10.14218/JCTH.2020.00073 -
Revista Da Associacao Medica Brasileira... 2019To review articles that evaluated the prevalence of Raynaud's phenomenon of occupational origin. (Review)
Review
OBJECTIVE
To review articles that evaluated the prevalence of Raynaud's phenomenon of occupational origin.
METHODS
The search for articles was carried out in the Medline (via PubMed), Embase, Web of Science, Scientific Electronic Library Online (SciELO), and Latin America and Caribbean Health Sciences Literature (Lilacs) databases.
RESULTS
64 articles were obtained from the electronic search; 18 articles met the eligibility criteria. All studies discussed the exposure to vibrations in the upper limbs. In 6 of them, the thermal issue was directly or indirectly addressed. No studies have addressed exposure to vinyl chloride.
CONCLUSIO
In general, a higher prevalence of Raynaud's phenomenon was found among vibratory tool operators compared to non-exposed workers, with an increase in the number of cases the higher the level of vibration and the time of exposure. Cold is a triggering and aggravating factor of the Raynaud phenomenon and seems to play an important role in the emergence of vascular manifestations of the hand-arm vibration syndrome.
Topics: Cold Temperature; Hand-Arm Vibration Syndrome; Humans; Occupational Diseases; Occupational Exposure; Prevalence; Raynaud Disease; Risk Factors; Vinyl Chloride
PubMed: 31721965
DOI: 10.1590/1806-9282.65.10.1314 -
ACS Sustainable Chemistry & Engineering Sep 2023The synthesis of the vinyl chloride monomer (VCM), employed to manufacture poly(vinyl chloride) (PVC) plastic, primarily relies on oil-derived ethylene, resulting in...
The synthesis of the vinyl chloride monomer (VCM), employed to manufacture poly(vinyl chloride) (PVC) plastic, primarily relies on oil-derived ethylene, resulting in high costs and carbon footprint. Natural gas-derived ethane in VCM synthesis has long been considered a transformative feedstock to lower emissions and expenses. In this work, we evaluate the environmental potential and economics of recently developed catalytic ethane chlorination technologies for VCM synthesis. We consider the ethylene-based business-as-usual (BAU) route and two different ethane-based processes evaluated at their current development level and their full potential, , ideal conversion and selectivity. All routes are assessed under two temporal scenarios: present (2020) and prospective (2050). Combining process simulation and life cycle assessment (LCA), we find that catalytic ethane chlorination technologies can lower the production cost by 32% at their current development state and by 56% when considering their full potential. Though environmentally disadvantageous in the 2020 scenario, they emerge as more sustainable alternatives to the BAU in the 2050 scenario, reducing the carbon footprint of VCM synthesis by up to 26% at their current state and up to 58% at their full potential. Going beyond VCM synthesis, our results highlight prospective LCA as a powerful tool for assessing the true environmental implications of emerging technologies under more decarbonized future energy scenarios.
PubMed: 37680580
DOI: 10.1021/acssuschemeng.3c03006 -
Environmental Health Perspectives Oct 1976The various adverse biological effects of vinyl chloride appear to be dependent upon the metabolic conversion of this compound into chemically reactive metabolites. The... (Review)
Review
The various adverse biological effects of vinyl chloride appear to be dependent upon the metabolic conversion of this compound into chemically reactive metabolites. The metabolism of vinyl chloride in mammals and in man, including the formation of monochloroacetic acid and some identified sulfur conjugates is reviewed. Hepatic microsomal mixed function oxidases from rats, mice, and humans were equally effective in transforming vinyl chloride into alkylating agents in vitro. Two of the enzyme reaction products, i.e., chloroethylene oxide and 2-chloroacetaldehyde, showed potent genetic activity in microorganisms and Chinese hamster V79 cells. The role of liver microsomal enzymes in the generation of electrophilic mutagenic vinyl chloride metabolites is discussed.
Topics: Animals; Biotransformation; In Vitro Techniques; Liver; Microsomes, Liver; Mixed Function Oxygenases; Mutagens; Rats; Saccharomyces; Salmonella typhimurium; Time Factors; Vinyl Chloride; Vinyl Compounds
PubMed: 799962
DOI: 10.1289/ehp.7617193 -
Polymers Jul 2022Bearing in mind the aspiration of the world economy to create as complete a closed loop of raw materials and energy as possible, it is important to know the individual... (Review)
Review
Bearing in mind the aspiration of the world economy to create as complete a closed loop of raw materials and energy as possible, it is important to know the individual links in such a system and to systematise the knowledge. Polymer materials, especially poly(vinyl chloride) (PVC), are considered harmful to the environment by a large part of society. The work presents a literature review on mechanical and feedstock recycling. The advantages and disadvantages of various recycling methods and their development perspectives are presented. The general characteristics of PVC are also described. In conclusion, it is stated that there are currently high recycling possibilities for PVC material and that intensive work is underway on the development of feedstock recycling. Based on the literature review, it was found that PVC certainly meets the requirements for materials involved in the circular economy.
PubMed: 35893999
DOI: 10.3390/polym14153035