Following apple harvests in America, the chemical diphenylamine, better known as DPA, is often sprayed to prevent "storage scald" or brown spots on the fruit, according to Washington State University, reported Mother Jones.
While not harmful on its own, DPA can break down into a carcinogen. The U.S. Environmental Protection Agency currently allows up to 10 parts per million DPA residue on domestic apples—100 times that of Europe's regulation.
In 2010, the U.S. Department of Agriculture monitored DPA residue on American-grown apples and found the chemical on 80 percent of them.
To protect its citizens, Europe is banning the sale of American apples in grocery stores.
The take away? Stick to organic apples whenever possible, and support your local farmers' market.
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