Daily News Archive
From April 11, 2002
Finds Fault with Chemical Thought to be "Safer"
Chemicals meant to be new and improved in the way of health and safety may not be all they're cracked up to be. Researchers reported findings on Tuesday regarding a class of chemicals called phenyltins, intended to replace older carcinogenic chemicals. They found that one of these, the agricultural chemical triphenyltin, could damage important cancer-fighting cells called lymphocytes.
The researchers used lymphocyte samples from normal human donors and exposed them to varying levels of phenyltins in test tubes. When these human cells were exposed to triphenyltin for one hour, their ability to fight tumor cells was reduced by 50 to 60 percent. What was even more shocking to the scientists was that this immune suppression continued even after exposure to triphenyltin was halted, for as long as five to six days. The study's lead scientists Margaret Whalen of Tennessee State University in Nashville, commented, "The results indicate that brief exposures to triphenyltin can cause persistent suppression of human immune system function."
Phenyltins are already known to contaminate water, fish and sediment. Researchers say the next step will involve testing agricultural workers, the main component of the population exposed to this chemical, to see if triphenyltin is in their blood samples. Of her research Whalen said, "These chemicals were made to replace things that are more toxic. This was considered an improvement on things that were used in the past."