Chicken bought and sold in grocery stores throughout the country are likely tainted with the known carcinogenic inorganic arsenic and should be banned by the Food and Drug Administration.

This is the conclusion researchers from the John Hopkins Center for a Livable Future at the Bloomberg School of Public Health came to in the first study to show concentrations of specific forms of arsenic, for example inorganic versus other forms, in retail chicken meat and to compare those concentrations based on whether or not it was raised with arsenical drugs.

Published in the journal Environmental Health Perspectives, the analysis included chicken samples purchased from 10 U.S. cities taken between December 2010 and 2011, the same period in which Pfizer’s arsenic-based drug roxarsone was available to poultry companies looking to add it to their feed in order to promote growth, prevent parasites and improve meat pigmentation in their chickens.

Sure enough, researchers found that meat containing roxarsone also showed levels of inorganic arsenic four times higher than the USDA Organic chicken samples, which were banned from using roxarsone and other arsenicals.

In July 2011, Pfizer voluntarily removed roxarsone from the U.S. market; however, the company continues to sell the drug overseas and is free to market it to the U.S. again at any time. Furthermore, the company continues to market the arsenical drug nitarsone, which is chemically similar to roxarsone, within the country

Regarding Pfizer’s decision to halt the sale of roxarsone, lead author Keeve Nachman calls it a“good thing in the short term,” admitting, however, that it “isn’t a real solution.”

“Hopefully,” he said in a press release, “this study will persuade FDA to ban the drug and permanently keep it off the market.”

Exposure to inorganic arsenic has been linked to lung, bladder and skin cancers as well as other conditions, including heart disease, type 2 diabetes, cognitive deficits and adverse pregnancy outcomes.