"Excreted Tamiflu Found in Rivers"

"The premier flu-fighting drug is contaminating rivers downstream of sewage-treatment facilities, researchers in Japan confirm. The source: urinary excretion by people taking oseltamivir phosphate, best known as Tamiflu.

Concerns are now building that birds, which are natural influenza carriers, are being exposed to waterborne residues of Tamiflu’s active form and might develop and spread drug-resistant strains of seasonal and avian flu.

For their new study, Gopal Ghosh and his colleagues at Kyoto University sampled water discharged from three local sewage treatment plants and water at several points along two rivers into which the treated water flowed. Sampling started early in December 2008, as flu season got underway. The researchers sampled again at the height of the seasonal flu’s onslaught in early February and again as infection rates waned."

Janet Raloff reports for Science News September 30, 2009.