A story is blazing around the blogosphere about a ten year old girl having an anaphylactic reaction to a blueberry pie. Physicians supposedly traced the reaction to streptomycin used as a pesticide on the blueberries. The account is spreading like wildfire with warnings about how an “antibiotic reside in food may cause severe allergies.” The reference is to a paper in the September issue of Annals of Allergy, Asthma and Immunology, a reputable publication. But there is a problem. The September issue is not yet out. So how do we know about the case? Because the Journal has put out a press release hyping the story. Scientific journals, just like any other publication, vie for readership and subscriptions, so they do seek attention. But here we are talking about a story that has some questionable features that cannot be checked because the actual paper is not yet available.
So what are these questionable features? First of all, the use of antibiotics as pesticides is rare. In Canada, streptomycin is registered only for use against “fire blight,” a destructive bacterial disease that can strike pear and apple trees. It cannot be used on blueberries. In the U.S. it may also be used on tomatoes and is even allowed in organic agriculture because it comes from a natural source, the bacterium Streptomyces griseus. The use of streptomycin is uncommon. Any suggestion that antibiotics are widely used as pesticides is simply wrong. The press release states that “as far as we know, this is the first report that links an allergic reaction to fruits treated with antibiotic pesticides.” Since streptomycin has been allowed for decades, and this is the first time a problem has cropped up, we are not looking at a highly significant problem. If indeed the problem was streptomycin.
We’ll have to wait to see what the case report actually says about how the reaction was linked to the antibiotic. Streptomycin breaks down quickly in the environment and the prescribed pre-harvest interval for its use is long so it would not be expected to show up in any marketed food. It is worth mentioning that at one time or another traces of fifty two pesticides have been detected on blueberries, but never streptomycin. For now, the story is more along the lines of the impropriety of an alarmist press release before the details of the actual study are made available.