Have you ever heard of DPA, also called diphenylamine? This is a chemical used widely on apples after they have been harvested. DPA is used to prevent what the industry calls storage scald -brown spots that appear on the fruit when it has been stored for several months. In 2008 the European Food Safety Authority began wondering if this chemical was safe for human consumption and began asking the chemical industry to provide safety information for DPA.
What was found was that from what is currently understood DPA isn’t harmful on its own but when it breaks down it forms a family of carcinogens called nitrosamines— certainly not a chemical compound you want on your apple. When this information came to be know, the European food safety regulators knew it was time to get as much safety information about it as possible and right away they decided they needed to take action. After determining through study that three unknown chemicals were found on DPA treated apples, the EFSA felt they did not know enough about whether or not these chemicals were in fact nitrosamines and decided to make using DPA on apples in Europe illegal. In March they even cut the tolerable level of DPA they would allow on imported apples to 0.1 parts per million.
As a result of tests done in 2010 by the Environmental Working Group (EWG) which found 80% of apples on US produce shelves contain on average 0.42 ppm of DPA, Europe will be cutting its imports unless DPA numbers can drastically reduce. How will North Americans respond though? With there being 4 times more DPA than what’s allowable in Europe, American standards seem much more lenient and the care taken to protect citizens from hazardous chemicals is not as strict a priority. Interestingly the Environmental Protection Agency (EPA) allows DPA residues of up to 10 ppm on apples -that is 100 times what is allowable in Europe!
Earlier this year three scientists in the U.S. EPA Office of Pesticides, which is tasked with pesticide safety reviews, told EWG they were unaware of the new European ban and import restrictions. They said the agency had no plans to reassess DPA safety in light of the European actions.
Although it is unknown as to whether or not DPA-treated apples present health risks, Europe has chosen to hold off until more is known about the chemical. A practice that makes perfect sense to me. Why use something potentially hazardous when one you don’t have to and two you don’t know yet if it’s safe? If you are a big apple eater, the EWG suggests buying organic.