Shrimp cocktail is a popular holiday appetizer, but may not be the healthiest menu choice. Researchers at Texas Tech University have found evidence of antibiotics in samples of farm-raised shrimp of international origin imported onto U.S. grocery shelves. The antibiotics present included nitrofuranzone, a probable human carcinogen. Two samples of the seafood tested in major cities contained levels of nitrofuranzone that were 28 and 29 times higher than the amount allowed by the U.S. Food and Drug Administration. Domestic shrimp harvested from the Gulf of Mexico also contained carcinogens and toxicants, according to a recent article by GreenMedInfo.com.

Equally unsettling, most farm-raised shrimp is far from sustainable, says Oregon researcher J. Boone Kauffmann, who estimates that 50 to 60 percent of shrimp farms worldwide are built on cleared mangrove areas. The shrimp produced from these farms have a carbon footprint up to 10 times higher than beef from cows raised on cleared Amazon rainforest areas.