Zoetis Animal Health, maker of
Histostat, asked the government to withdraw all feed-additive uses by the end
of this year. It stopped selling the product this fall.
Nitarsone has held approval for
the prevention of blackhead disease (histomoniasis) in turkeys and chickens,
but was mostly used in turkey rations.
Arsenic is in the environment as a
naturally occurring substance or as a contaminant and is found in water, air,
soil, and food.
Published scientific reports have
indicated that organic arsenic, the less toxic form of arsenic present in the
arsenic-based animal drugs, could transform into inorganic arsenic, a known
carcinogen.
