Does exposure to vinylidene chloride (VDC) cause malignant mesothelioma?  According to a new study, the answer may be yes.  A two-year National Toxicology Program study found that a particular species of male rat exposed to VDC resulted in a marked increase in malignant mesothelioma.  According to the study, “a chronic, pro-inflammatory environment associated with VDC exposure may exacerbate disturbances in oncogene, growth factor, and cell cycle regulation, resulting in an increased incidence of mesothelioma.”  The study concludes that VDC exposure may lead to cytotoxicity and DNA damage resulting in hyperplasia and genetic instability that are important risk factors in the development of cancer.

Vinylidene chloride is used to make various chemical intermediaries and is used in the manufacture of several different materials including films, coatings, plastic pipes, conduit, flooring, sheeting, and cables.  The National Institute of Occupational Safety and Health (NIOSH) considers VDC an irritant to the eyes, skin, and throat as well as a potential carcinogen.

The National Toxicology Program is located at the National Institute of Environmental Health Sciences and is part of the National Institutes of Health.  The study can be found at