Mice ingesting the compound tributyltin pass effects to grandchildren

By Erin Wayman

Web edition: January 14, 2013
Print edition: February 9, 2013; Vol.183 #3 (p. 18)

Exposure in the womb to a chemical used in PVC and ship paint promotes obesity in mice. And the effect is long-lasting: The mice’s grandchildren were also fat despite no exposure to the chemical.

The work shows that the effects of an obesogen — a chemical that encourages fat accumulation — can be passed on to future generations not exposed to the chemical, researchers report online January 15 in Environmental Health Perspectives.

The compound tributyltin is often added to PVC as a stabilizer and to marine paint as an antifouling agent. Raquel Chamorro-García of the University of California, Irvine and colleagues fed pregnant mice tributyltin in their drinking water at quantities similar to what people might ingest through house dust and other sources. The mice gave birth to pups that developed more and larger fat cells, as well as fattier livers, compared with unexposed pups.

These changes appear to be permanent. The children and grandchildren of these mice also had increased amounts of body and liver fat.

The findings confirmed previous work showing that tributyltin affects the function of a gene that regulates body fat production and reprograms certain stem cells to become fat cells rather than bone cells.