A trio of food safety and environmental advocacy groups Thursday filed suit against the U.S. Food and Drug Administration, saying the agency has not sufficiently proven that ractopamine, a drug fed to pigs, cattle and turkey, is safe for animals, humans who eat them, or the environment. Ractopamine, a beta-agonist, increases the rate at which animals convert feed to muscle by mimicking the body’s stress hormones. It is typically fed to livestock in the weeks before slaughter to promote weight gain. The FDA approved ractopamine for use in pig feed in 1999, but since that time the potential affect of the drug residue on humans and on the environment has come into question. Several governments, including the European Union, China and Russia have banned the import of ractopamine-fed pigs, saying they don’t know enough about the drug’s safety to approve it in food animals.   Now three concerned groups — Center for Food Safety, the Center for Biological Diversity and the Sierra Club — are claiming that FDA, after approving 11 new uses for the drug, has not done enough to test the potential harmful effects of ractopamine on people, animals and the environment. The FDA has not conducted the environmental assessments needed to prove that the drug is safe for the humans, plants and animals living around farms where it’s used, says the complaint, filed with the United States District Court of Appeal for the Northern District of California. This failure to conduct a proper assessment, they argue, is a violation of the National Environmental Policy Act. “FDA is basing controversial drug approvals on incomplete and inadequate environmental analyses,” said Paige Tomaselli, senior attorney for Center for Food Safety in a press release Thursday. “These drugs in our food supply impact the environment, thousands of farm workers, millions of consumers, and billions of animals. FDA cannot continue to abdicate its responsibility to do its job.” Ractopamine was first approved for use in pigs in 1999 under the brand name Paylean. FDA found that its manufaturer, Elanco, a division of Ely Lilly, sufficiently proved its safety in animals and for human exposure at the doses at which it would be used. Later on, the drug was approved for use in cattle (as Optaflexx) in 2003, and for use in Turkeys (as Topmax) in 2008. But the group that filed the Thursday complaint against the agency says more research needs to be done to keep up with the widespread and new uses of the drug — now given to 60 to 80 percent of pigs raised for food — and to track its effects on the environment. Ractopamine is excreted through animal feces, so if enough survives in the feces, it can be spread through fertilizer in fields, and could from there run off into water. The complaint says Topmax was unlawfully approved, as were subsequent ractopamine-based combination drugs, because the agency did not consider all possible repercussions for the environment when approving these new uses of the compound. Elanco has acknowledged the “potential leaching into the soil and groundwater from confinement areas” and the fact that the drug may enter waterways, a fact the complaint says necessitates more thorough research into its effects on these ecosystems and the people and animals in them. The groups also claim that there is insufficient research on the danger of ractopamine to humans. They cite one particular study, the only one conducted directly on humans, presented as part of Elanco’s safety tests to FDA, pointing out that one six male subjects were tested. However, the study’s author notes that this small human test was done only to determine which animal better reflected the human metabolization of the drug. In its report on the toxicology of ractopamine, FDA says that exposure to the drug for humans can lead to heightened heart rate and a higher systolic blood pressure. Over time, exposure to the drug can lead to abnormal heart rhythms, tremors, nervousness and metabolic problems. The drug is safe, however, says the agency, since the residues left in animals after slaughter don’t reach harmful levels. In tests of ractopamine residues in muscles, kidneys and liver, levels were in the parts per billion range, falling well below the concentration of acceptable daily intake (.25 parts per million in muscles, .75 ppm in liver and 1.5 ppm in kidney and fat). The groups who filed Thursday’s lawsuit say more must be known about human exposures to ractopamine now that the drug has expanded uses and a larger presence in the environment. To read more about the controversy of ractopamine safety, see past Food Safety News coverage: FDA Petitioned to Lower Ractopamine Limits for Meat, Review Health Impacts Codex Adopts Ractopamine Limits for Beef and Pork  Animal Drug Used Widely in US Meat the Subject of Trade Dispute