It’s often hard to know just what constitutes contamination, and it also seems to depend upon where you live. The presence of vitamin D in milk is not considered contamination by most people, but the presence of tuberculosis is. So how the substance is labeled, either good or bad, determines whether we call it a contaminant.
That is really universal across the globe, but what isn’t universal is how substances in the food supply are treated when they have questionable, no, or little evidence of being bad.
Ractopamine is a good example of this. While the substance that makes pigs and cattle build heavier muscles is banned in 160 countries, it isn’t in others such as the U.S. Perhaps as evidence of the slim margins pig farmers work on, using ractompamine for pigs only increases their weight by about three pounds at slaughter leaving the farmer a whopping $3.64 more profit when factoring in lower feed costs and if pork is wholesaling at $ .60 per pound, according to Purdue University.
“Considering all studies, the FEEDAP Panel concludes that ractopamine is not mutagenic and is unlikely to present a carcinogenic risk to consumers,” writes the European Food Safety Authority. But that was basically all the organization could determine from all studies it looked at. So in the European Union, the inability of the studies to support a maximum residue level (MRL) of the material as being benign to humans means it is NOT something they should ingest. Consequently it is banned in any concentration as a residue in pork and beef.
In the U.S., and 24 other countries, apparently the interests of the agricultural community and the manufacturers of the ractopamine products take precedence. Until ractopamine is shown to have negative effects on humans, it is allowed to be used and there is no clearance time either, meaning the material does not have to be eliminated from the animals before slaughter.