A CONTRACEPTIVE pill for cockroaches that also kills the insects within
days could soon go on sale in the US. Developed by Heather Wren and her
colleagues at Virginia Polytechnic Institute and State University, Blacksburg,
the 鈥減ill鈥� is a mixture of xanthine鈥攁 chemical found in coffee and
potatoes鈥攁nd oxypurinol, an active compound in gout treatments.
When the insects consume the chemicals, they can no longer store nitrogen.
Females then cannot make the egg cases in which their young develop. And insects
of both sexes die within days without nitrogen.