It’s always nice when science seems to confirm a long-held bias. I remember when there was no research to validate the assumption that organically grown foods are “better” than the conventional, more readably available alternative. Then the evidence started trickling in—first that organic practices are clearly better for keeping the soil healthy, then that organically grown food has more nutrients than conventional.
A team of researchers, led by a couple of U of W professors, has piggy-backed on a long-running multi-ethnic study of cardiovascular disease among over 6 thousand participants, men and women between the ages of 45 and 84. They wanted to see if eating conventionally grown produce results in exposure to pesticide residues. (Here’s a link to the preliminary report, if you like looking at source material, as I do, when I can get access.)
The study included the following foods: apples, apple juice, asparagus, blueberries, broccoli, cantaloupe, grapes, green beans, collard greens, lettuce, mangoes, nectarines, oranges, peaches, pears, spinach, strawberries, summer squash, sweet potatoes and tomatoes. (These were chosen because data was available on both consumption and pesticide residues.)
After completing a questionnaire about their preferences for organic or conventional produce, and the relative frequency of choosing each item, participants gave a urine sample, which was tested for 4 types of dialkylphosphates (DAPs): dimethylphosphate, or DMP, dimethylthiophosphate, DMTP, diethylphosphate, DEP, and diethylthiophosphate, DETP.
But enough alphabet soup. The results? People who ate the most organic produce also ate more produce overall (3.7 servings per day). That makes sense to me; I fit both those categories, and I do eat both organic and conventional produce. And, yes, the results show that people who eat organic produce have lower levels of organophosphates in their urine.
Why do we care? Because these pesticide residues affect health. Remember Gulf War Syndrome? Turns out the neurological abnormalities of Gulf War syndrome were caused by exposure to organophosphate chemical nerve agents. (I got that from Wikipedia.)
Chemical warfare exposure is not the same thing as exposure to pesticides in food, I know. Pesticide residue in our food supply is a problem that disproportionally affects children. High prenatal maternal urinary DAP levels are associated with attention problems and attention deficit/hyperactivity disorder in 5 year-old children, poorer intellectual development in 7 year-old children, and decreased cognitive development in 1 year-old children, in 6-9 year-olds, according to the study report.
But don’t despair. Here’s another link, to the Environmental Working Group’s list of conventional foods listed by prevalence of pesticide residues. So, if you see something you eat often that is high in pesticides, you can choose organic instead for that item.
And here’s their list of “clean” conventional produce, starting from the cleanest: avocados, sweet corn, pineapples, cabbage, frozen sweet peas, onions, asparagus, mangoes, papayas, kiwis, eggplant, grapefruit, cantaloupe, cauliflower and sweet potatoes.
They update this list from year to year—it’s a great resource if you’re concerned about exposure to these kinds of toxins.