Occupational exposure to vinyl chloride and liver diseases

Abstract

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.

Occupational exposure and cancer: an umbrella review

“…Moreover, to further research this interaction, other studies have recently investigated the association between exposure and other forms of liver cancer, such as hepatocellular carcinoma 62 . Their latest method has been the in vitro study of the genotoxicity assessment of vinyl chloride 63,64 .…”

Associations between residential exposure to volatile organic compounds (VOCs) and liver injury markers

“…Numerous epidemiologic studies have demonstrated that exposures to VOCs were associated with various forms of liver injury and dysfunction ranging from elevated liver enzyme levels to steatohepatitis and liver cancer. For instance, it is well-documented that exposure to vinyl chloride, a historic occupational VOC, was associated with steatohepatitis in rubber plant workers, with some workers exhibiting hemangiosarcoma, a rare form of cancer affecting liver sinusoidal cells (Cave, et al, 2010;Fedeli et al, 2019). Other studies focusing on petroleum and auto-industry workers demonstrated that workers who were occupationally exposed to VOCs such as gasoline and other aromatic hydrocarbons, had higher mean levels of liver test results (ALT, AST and ALP) as well as total and conjugated bilirubin, when compared to non-worker controls (Asefaw et al, 2020;Egbuonu and Nkwazema, 2015;Mohammadi et al, 2010).…”

Factors Associated with Urinary 1-Hydroxypyrene and Malondialdehyde among Adults near a Petrochemical Factory: Implications for Sex and Lifestyle Modification

“…They are associated with carcinogenic properties, respiratory problems, and kidney diseases among workers in petroleum refineries, coke ovens, and aluminum production [3,7,8]. The release of hazardous substances from PICs is also thought to increase the risk of cancer and chronic diseases among people living in the neighborhood [1,2,9,10]. Many studies have shown that PAHs are produced by the incomplete combustion of organic materials, and can be metabolized as 1-hydroxypyrene (1-OHP) and excreted through the feces and urine [2,3,11].…”