The arsenic ban, sponsored by Del. Tom Hucker, a Montgomery County Democrat, affects the drug Roxarsone, which includes arsenic among its components, reports the Baltimore Sun.

Industry advocates contend that the drug is an effective means of controlling the spread of disease in chicken houses, but environmentalists say its use results in the release of 30,000 pounds a year of a known carcinogen into the state's soil and waters.

Mr Hucker said it took three years to push the legislation through over the opposition of the state's poultry industry and pharmaceutical interests.

"I'm glad common sense prevailed and the General Assembly stood up to the lobbyists and passed the ban this year," he said.