SCIENCE / MEDICINE : Fumigant Alters Chromosome

A chemical that is widely used in fumigating grain and for processing silicon in the electronics industry can cause long-lasting chromosomal defects in humans exposed to it on the job, researchers reported last week in Science. Chromosome defects of the type observed can cause cancer and, in fact, epidemiological studies of workers who use the chemical, called phosphine, have shown a sharply increased incidence of blood cancers such as non-Hodgkin lymphoma.

The team of researchers, headed by pathologist Vincent F. Garry of the University of Minnesota, studied white blood cells obtained from 24 male workers who apply fumigants to grain, 20 of whom used phosphine. They found visible defects in the 23 pairs of chromosomes that store the genetic blueprint of humans in the workers who used phosphines but not in those who did not.

The defects were of two types. Some were short term, persisting for only a few days after exposure to the phosphine. Others lasted for at least six months. The researchers are now conducting further studies to see if these defects are associated with cancer.