Research has indicated that the horse meat consumed by humans could be laced with phenylbutazone.
Penylbutazone, which is more commonly known as bute, is a drug that is used to treat musculoskeletal injuries in horses. It is not supposed to be used in meat meant for consumption.
"The permissive allowance of such horsemeat used for human consumption poses a serious public health risk", said Drs Nicholas Dodman, Ann Marini and Nicolas Blondeau, who have authored a research paper. The authors followed 18 race horses who received bute and were then sent to slaughterhouse.
The study also said that some 67 million pounds of American horsemeat was sent overseas for human consumption last year.
The details of the paper are available in the journal Food and Chemical Toxicology.