The “body burden” is a term used to signify an individual’s exposure to and absorption of toxic influences related to the pollution of our environment. One of the most insidious and ubiquitous toxins is pesticides. After all, these are chemicals which are designed to be deadly. What kills fungi, insects, plants, rodents may not kill humans, but could severely disrupt the function of the digestive, hormonal and neurological systems as well as disturb cellular metabolism. Citing research performed and published by the Agency for Toxic Substances and Disease Registry, the Centers for Disease Control and Prevention, and the Environmental Protection Agency, the public information organization Environmental Working Group has disseminated much useful information about the pre valency of pesticides.
The actual effect of various pesticides is not fully understood for a variety of reasons. For one, current exposure to toxic contaminants is so universal that it can be next to impossible to isolate the effects of any specific one. As I have mentioned in a previous column, research conducted on a test group of 9 “healthy” volunteers revealed that these individuals averaged 91 toxic chemicals in their body tissues.
Other issues that complicate research into the effect of pesticides relate to time of exposure and dosage. Again, it is hard to quantify the long term effects of lose dose exposure. And, while a specific pesticide may not have tested as toxic in a laboratory rat, and therefore assumed to be safe, this is little guarantee that exposure to the same pesticide during pregnancy or at early developmentally sensitive stages in life will not have toxic effects.
In fact, the EWG cites research showing “that low doses at a susceptible moment of development can cause more of an effect than high doses (vom Saal 1997, Alworth 2002, Hayes 2003). This is particularly relevant to childhood and fetal exposures via food and water where the timing of the exposure is at least as important as the dose.”
At any rate, there are many pesticides which are generally considered to be “estrogen mimics” or "endocrine disrupters". Well known examples are: DDT, which has been shown to have anti-androgenic or de-masculinizing properties; vinclozolin which is a heavily used fungicide that is also anti-androgenic; a DDT relative called endosulfan which has estrogenic properties; and atrazine, a weed killer with broad hormonal activity, that contaminates the drinking water of about 20 million people in the United States.
It would be wonderful if everyone could avoid pesticide exposure. But their prevalence in the soil and our foods makes that impossible. One of the options we have though is to choose the foods we eat with greater care - eating organically where possible, or at least avoiding the non-organic foods which have been found to be more laden with pesticides.
In fact, pesticide contamination of a typical non-organic fruit and vegetable varies quite a bit depending on the type. For instance, research data shows that pesticide contamination in peaches is likely to be double that of apricots, and nearly 16 times more than pineapples. Amongst vegetables, spinach tops the list, some 80 times more toxic than sweet corn.
The EWG has recently published its “Shopper's Guide to Pesticides in Produce”, ranking pesticide contamination for nearly fifty common fruits and vegetables. This information is taken from an analysis of a decade of published research conducted by the U.S. Department of Agriculture and the Food and Drug Administration.
The rankings are derived from a composite score of contamination based on the following 6 factors:
Percent of the samples tested with detectable pesticides Percent of the samples with two or more pesticides Average number of pesticides found on a sample Average amount (level in parts per million) of all pesticides found Maximum number of pesticides found on a single sample Number of pesticides found on the commodity in total
Fruits tended to contain more pesticides than vegetables; eight out the “top 12” were fruits. Vegetables such as asparagus, avocado, broccoli, corn, cauliflower, onions and peas were the least contaminated.
So, if one is inclined to buy organic foods for at least a portion of the grocery list, it makes sense to concentrate on higher ranking items, especially those on the following list of the top “Dirty Dozen”. They are as follows:
• Apples • Bell Peppers • Celery • Cherries • Imported Grapes • Nectarines • Peaches • Pears • Potatoes • Red Raspberries • Spinach • Strawberries
According to the analysis, the least contaminated dozen includes:
• Asparagus • Avocados • Bananas • Broccoli • Cauliflower • Corn (sweet) • Kiwi • Mangos • Onions • Papaya • Pineapples • Peas (sweet)
The Complete list of test results with the relative score (the lower the better) is as follows:
1 Peaches 100 2 Strawberries 89 3 Apples 88 4 Spinach 85 5 Nectarines 85 6 Celery 83 7 Pears 80 8 Cherries 76 9 Potatoes 67 10 Sweet Bell Peppers 66 11 Raspberries 66 12 Grapes - Imported 64 13 Carrots 57 14 Green Beans 57 15 Hot Peppers 55 16 Oranges 53 17 Apricots 51 18 Cucumbers 51 19 Tomatoes 48 20 Collard Greens 48 21 Grapes - Domestic 47 22 Turnip Greens 41 23 Honeydew Melons 40 24 Lettuce 40 25 Kale 39 26 Mushrooms 36 27 Cantaloupe 36 28 Sweet Potatoes 35 29 Grapefruit 34 30 Winter Squash 34 31 Blueberries 30 32 Watermelon 27 33 Plums 26 34 Tangerines 25 35 Cabbage 25 36 Papaya 23 37 Kiwi 23 38 Bananas 19 39 Broccoli 18 40 Onions 17 41 Asparagus 16 42 Sweet Peas 13 43 Mango 12 44 Cauliflower 10 45 Pineapples 6 46 Avocado 4 47 Sweet Corn 1
Note: Grapes are divided into domestic and imported samples.