Occupational Exposure to Metal Working Fluids and Bladder Cancer: A Systematic Review

Metalworking fluids (MWFs) are complex compounds of oils and chemical additives widely used to cool and lubricate metal machining operations. When sprayed, MWF produces concentrations up to twice the allowable level of US ambient air pollution standards. The study was designed to assess possible relationships between occupational exposure to MWFs and the risk of bladder cancer. Literature entered the study was published from February 2000 to 2021 and provides information on exposure to metalworking fluids and the risk of bladder cancer. We searched PubMed, Scopus, and Web of Sciences from 2000 to 2021. The following subject and keywords were used in the search: ―bladder cancer‖ and ―metalworking fluids‖. Out of 8 studies, 4 were case-control and 4 were cohort and all of them had high NOS scores. The strong exposure-response relationship between bladder cancer and metalworking fluids reinforces the evidence for MWFs as a bladder carcinogen. The literature review in this study also shows that smoking can increase the risk of bladder cancer due to exposure to metalworking fluids.