Nearly three-fourths of the 6,953 produce samples tested by the U.S. Department of Agriculture in 2014 contained pesticide residues - a surprising finding in the face of soaring consumer demand for food without synthetic chemicals.
This year's update of EWG's Shopper's Guide to Pesticides in Produce™ reports that USDA tests found a total 146 different pesticides on thousands of fruit and vegetable samples examined in 2014. The pesticides persisted on fruits and vegetables tested by USDA - even when they were washed and, in some cases, peeled.
The USDA findings indicate that the conventional fruit and produce industries are ignoring a striking market trend: American consumers are voting with their pocketbooks for produce with less pesticide. Yet EWG’s Shopper's Guide to Pesticides in Produce™ recognizes that many people who want to reduce their exposure to pesticides cannot find or afford an all-organic diet. It helps them identify conventionally grown fruits and vegetables that tend to test low for pesticide residues. When they want foods whose conventional versions test high for pesticides, they can make an effort to locate organic versions.
EWG singles out produce with the highest pesticide loads for its Dirty Dozen™ list. This year, includes strawberries, apples, nectarines, peaches, celery, grapes, cherries, spinach, tomatoes, sweet bell peppers, cherry tomatoes, and cucumbers.
Each of these foods tested positive for a number of different pesticide residues and showed higher concentrations of pesticides than other produce.
EWG's Clean Fifteen™ list of produce least likely to hold pesticide residues consists of avocados, sweet corn, pineapples, cabbage, frozen sweet peas, onions, asparagus, mangoes, papayas, kiwis, eggplant, honeydew melon, grapefruit, cantaloupe, and cauliflower. Relatively few pesticides were detected on these foods, and tests found low total concentrations of pesticides on them.
For the fourth year, we have expanded the Dirty Dozen™ with a Plus category to highlight two types of food that contain trace levels of highly hazardous pesticides. Leafy greens - kale and collard greens - and hot peppers do not meet traditional Dirty Dozen™ ranking criteria but were frequently found to be contaminated with insecticides toxic to the human nervous system. EWG recommends that people who eat a lot of these foods buy organic instead.
Leafy greens and hot peppers carry toxic pesticides.
Two American food crops - leafy greens and hot peppers - are of special concern for public health because residue tests conducted by the U.S. Department of Agriculture have found these foods laced with particularly toxic pesticides. Among the chemicals at issue are organophosphate and carbamate insecticides. These are no longer detected widely on other produce, either because of binding legal restrictions or voluntary phase-outs.
Leafy greens did not qualify for EWG's Dirty Dozen™ list this year under the traditional EWG Shopper's Guide rating system, which highlights produce with the highest number and concentrations of pesticides. Still, because of the extraordinary toxicity of the pesticides detected on them, we are highlighting them in this special Plus section.
USDA tests of 739 samples of hot peppers in 2010 and 2011 (USDA 2010, 2011) found residues of three highly toxic insecticides — acephate, chlorpyrifos, and oxamyl — on a portion of sampled peppers at concentrations high enough to cause concern. These insecticides are banned on some crops but still allowed on hot peppers.
In tests conducted in 2007 and 2008, USDA scientists detected 51 pesticides on kale and 41 pesticides on collard greens (USDA 2007, 2008). Several of those pesticides — chlorpyrifos, famoxadone, oxydemeton, dieldrin, DDE and esfenvalerate — are highly toxic. Although many farmers may have changed their pesticide practices since 2008, chlorpyrifos and esfenvalerate are still permitted on leafy greens. Organochlorine pesticides DDE and dieldrin were banned some years ago but persist in agricultural soils and still make their way onto leafy greens grown today.
EWG recommends that people who frequently eat leafy greens and hot peppers buy organic varieties. If you cannot find or afford organic types, cook them, because pesticides levels typically diminish when food is cooked.
The federal Food Quality Protection Act of 1996 mandated that the U.S. Environmental Protection Act improve its regulation of pesticides and reduce the risks of pesticide exposure for children. The act prompted EPA to restrict the use of many chemicals, including organophosphate pesticides, which are potent neurotoxins. Even in low doses, they can impair children's intelligence and brain development. Over the past two decades, organophosphates have been withdrawn from many agricultural uses and banned from household pesticides. Yet they can still be applied to certain crops.
Several long-term studies of American children initiated in the 1990s found that children's exposures to toxic organophosphate insecticides in not only agricultural communities but also cities were high enough to cause subtle but lasting damages to their brains and nervous systems (Bouchard 2011, Rauh 2011, Engel 2011).
The EPA and some in the agriculture industry argue that restrictions enacted after these children were born would ensure that contemporary children's exposures to these pesticides from food are safe.
However, a study led by Stephen Rauch of British Columbia's Children's Hospital and published in 2012 in the scientific journal Environmental Health Perspectives found decreases in infant birth weight and shorter pregnancies among 300 Ohio mothers exposed to organophosphates during pregnancy (Rauch 2012). These pregnancies occurred after major organophosphate restrictions took effect in the early 2000s. The Rauch study indicates that organophosphate exposures must be further curtailed to protect children's health.
The EPA should continue to restrict toxic pesticides, including organophosphate and carbamate insecticides that are still allowed on many crops. Until this happens EWG will continue to publish a Dirty Dozen Plus™ list that highlights crops tainted with unusually risky pesticides. The USDA should expand its produce-testing program to conduct more frequent analyses of pesticide residues on popular foods. To name a few, kale, collard greens, strawberries, cherries and tomatoes have not been tested since 2009 and are overdue for retesting.
Most processed food typically contains one or more ingredients derived from genetically engineered crops. GMO food is not often found in the produce section of American supermarkets. A small percentage of zucchini, yellow squash and sweet corn in the produce cooler is GMO. Most Hawaiian papaya is GMO.
Other varieties of GMO foods are currently being tested. The USDA may approve them in the future. Since U.S. law does not require labeling of genetically engineered produce, EWG advises people who want to avoid GMO crops to purchase organically-grown foods or items bearing the "Non-GMO Project Verified" label. EWG recommends that consumers check EWG's Shopper's Guide To Avoiding GMO Food, and FoodScores database and EWG's Healthy Living App which can help identify foods likely to contain genetically engineered ingredients.
Smart shopping choices matter. People who eat organic produce eat fewer pesticides. A study by Cynthia Curl of the University of Washington published February 5, found that people who report they "often or always" buy organic produce had significantly less organophosphate insecticides in their urine samples, even though they reported eating 70 percent more servings of fruits and vegetables per day than adults reporting they "rarely or never" purchase organic produce (Curl 2015). Several long-term observational studies have indicated that organophosphate insecticides may impair children’s brain development.
In 2012, the American Academy of Pediatrics issued an important report that said that children have "unique susceptibilities to [pesticide residues'] potential toxicity." The pediatricians' organization cited research that linked pesticide exposures in early life and "pediatric cancers, decreased cognitive function, and behavioral problems." It advised its members to urge parents to consult "reliable resources that provide information on the relative pesticide content of various fruits and vegetables." One key resource, it said, was EWG's Shopper's Guide to Pesticides in Produce™ (AAP 2012).
With EWG's shopping tool, people can have the health benefits of a diet rich in fruits and vegetables with less exposure to pesticides.
EWG's Shopper's Guide to Pesticides in Produce™ ranks pesticide contamination on 48 popular fruits and vegetables based on an analysis of more than 35,200 samples taken by the U.S. Department of Agriculture and federal Food and Drug Administration. The USDA doesn't test every food every year. EWG generally uses the most recent sampling period for each food. However the USDA only tested 176 samples of strawberries during the last three months of 2014 so we included test data from 2009 as well. Nearly all the tests that serve as the basis for the guide were conducted by the USDA, whose personnel washed or peeled produce to mimic consumer practices. It is a reasonable assumption that unwashed produce would likely have higher concentrations of pesticide residues.
In order to compare foods, EWG looked at six measures of pesticide contamination:
For each metric, we ranked each food based on its individual USDA test results, then normalized the scores on a 1-100 scale, with 100 being the highest. A food's final score is the total of the six normalized scores from each metric. The Shopper's Guide™ Full List shows fruits and vegetables in order of these final scores.
Our goal is to show a range of different measures of pesticide contamination to account for uncertainties in the science. All categories were treated equally. The likelihood that a person would eat multiple pesticides on a single food was given the same weight as amounts of the pesticide detected and the percent of the crop on which any pesticides were found.
The EWG's Shopper's Guide™ is not built on a complex assessment of pesticide risks but instead reflects the overall pesticide loads of common fruits and vegetables. This approach best captures the uncertainties about the risks and consequences of pesticide exposure. Since researchers are constantly developing new insights into how pesticides act on living organisms, no one can say that concentrations of pesticides assumed today to be safe are, in fact, harmless.
EWG's Shopper's Guide to Pesticides in Produce™ aims to give consumers confidence that by following EWG's advice, they can buy foods with fewer types of pesticides and lower overall concentrations of pesticide residues.
AAP 2012. Organic Foods: Health and Environmental Advantages and Disadvantages. American Academy of Pediatrics Committee on Nutrition and Council on Environmental Health. e1406 -e1415. DOI: 10.1542/peds.2012-2579. http://pediatrics.aappublications.org/content/130/5/e1406
Bouchard M, Chevrier J, Harley K, et al. 2011. Prenatal Exposure to Organophosphate Pesticides and IQ in 7-Year Old Children. Environ Health Perspect 119(8): 1189–1195.
Curl CL, Beresford SAA, Fenske RA, et al. 2015. Estimating Pesticide Exposure from Dietary Intake and Organic Food Choices: The Multi-Ethnic Study of Atherosclerosis (MESA). Environmental Health Perspectives. Advanced publication February 5, 2015. DOI: 10.1289/ehp1408197 http://ehp.niehs.nih.gov/wp-content/uploads/advpub/2015/2/ehp.1408197.acco.pdf
Engel SM, Wetmur J, Chen J, et al. 2011. Prenatal Exposure to Organophosphates, Paraoxonase 1, and Cognitive Development in Childhood. Environ Health Perspect 119(8): 1182-1188.
Rauch SA, Braun JM, Barr DB, et al. 2012. Associations of Prenatal Exposure to Organophosphate Pesticide Metabolites with Gestational Age and Birth Weight. Environ Health Perspect. 120(7): 1055–1060.
Rauh V, Arunajadai S, Horton M, et al. 2011. 7-Year Neurodevelopmental Scores and Prenatal Exposure to Chlorpyrifos, a Common Agricultural Pesticide. Environ Health Perspect. 119(8): 1196-1201.
USDA. 2007. Pesticide Data Program: Annual Summary, Calendar Year 2007. U.S. Department of Agriculture. December 2008.
USDA. 2008. Pesticide Data Program: Annual Summary, Calendar Year 2008. U.S. Department of Agriculture. December 2009.
USDA. 2010. Pesticide Data Program: Annual Summary, Calendar Year 2010. U.S. Department of Agriculture. May 2012.
USDA. 2011. Pesticide Data Program: Annual Summary, Calendar Year 2011. U.S. Department of Agriculture. May 2013.
USDA. 2012. Pesticide Data Program: Annual Summary, Calendar Year 2010. U.S. Department of Agriculture, May 2012.
USDA. 2014a. Pesticide Data Program: Annual Summary, Calendar Year 2012. U.S. Department of Agriculture, February 2014.
USDA. 2014b. Pesticide Data Program: Annual Summary, Calendar Year 2013. U.S. Department of Agriculture, December 2014.
USDA. 2015. Pesticide Data Program: Annual Summary, Calendar Year 2014. U.S. Department of Agriculture, January 2016.