JACC Report 49 – Vinylidene Fluoride
JACC 049 : Vinylidene Fluoride (CAS No. 75-38-7) | November 2005
This report has been produced as part of the ECETOC Joint Assessment of Commodity Chemicals (JACC) programme. It presents a critical evaluation of data on the toxicity, ecotoxicity and environmental fate and impact of vinylidene fluoride (VDF). A hazard/risk assessment is required under current OECD/EU schemes , . In the USA, VDF is included in the Environmental Protection Agency (EPA) Chemical Right-to-Know Initiative . VDF, a colourless gas, is used mainly in the manufacture of polyvinylidene fluoride and of copolymers with chlorotrifluoroethylene or hexafluoropropylene; it is also used in smaller quantities in the manufacture of other fluorinated copolymers. VDF is sparingly soluble in water and any VDF released to the environment will distribute to the atmosphere, where it will degrade to formaldehyde and carbonyl fluoride. Formaldehyde occurs naturally in the atmosphere and is broken down to carbon dioxide and water; carbonyl fluoride, once absorbed into cloud droplets, will be hydrolysed to carbon dioxide and hydrogen fluoride. VDF does not cause depletion of the stratospheric ozone layer and it makes a comparatively negligible contribution to global warming and the formation of ground-level ozone (except for the additional carbon dioxide from breakdown). Model calculations predict that VDF will not be toxic to environmental organisms. No bioaccumulation and biomagnification in the food chain is expected. Biodegradation of VDF in water, sediment or soil is unknown, but is not considered of relevance since VDF will partition rapidly into the air. VDF has a low acute toxicity in laboratory animals, with no signs of cardiac sensitisation following short-term inhalation of high doses; longer-term exposure also results in a low level of toxicity. The effects are weak and relate to changes in blood chemistry (increased haemoglobin), degeneration of the vomeronasal organ, and mineralisation of the kidneys at high doses. VDF is metabolised to fluoroacetic acid, which could interfere with the citric acid cycle. VDF is not genotoxic either in vitro or in vivo, apart from some activity in a bacterial test. Although rats developed carcinomas in an early one-year oral study, subsequent lifetime inhalation studies in rats and mice showed no adverse effects at high doses. It is therefore unlikely that VDF has significant long-term toxic or carcinogenic properties. VDF has no effects on rat fertility or reproduction. Signs of impaired spermatogenesis found in an early study remained unconfirmed in two subsequent studies. A teratology study did not indicate any embryotoxic, foetotoxic or teratogenic effects at high concentrations.