The Dirty Dozen: Blueberries

By Dave Whitney, Produce Manager, Co-op Owner

Blueberries are back on the Dirty Dozen, with traces of several toxic pesticides.

We LOVE blueberries, in fact, Americans are eating three times as many blueberries as they did in the early 2000s. Unfortunately, this popular fruit is also part of a worrying trend – an increase in pesticide residues have led to blueberries’ return this year to EWG’s (Environmental Work Group) “Dirty Dozen,” showing up in 11th place.

EWG’s list is based on an analysis of Department of Agriculture data, which tests some fruit samples in certain years. Compared to the last time blueberries were tested, in 2014, more samples had detectable residues. Tests of 765 non-organic blueberry samples collected in 2020 and 2021 found more than 90 percent had pesticide residues, up from 81 percent with detectable residues in 2014.

The most troubling pesticides found on these latest samples are phosmet and malathion, chemicals known as organophosphate insecticides. They kill many types of insects and are toxic to the human nervous system, especially children’s developing brains. Phosmet was detected on more than 10 percent of blueberry samples, with malathion close behind at 9 percent. Phosmet is not approved for use in the European Union, and malathion is approved for use in greenhouses only. Yet the Environmental Protection Agency currently allows both for use on U.S. crops, putting blueberry fans at potential risk.

And that’s a problem, because children between the ages of two and five are especially fond of berries, which account for 5% of the total amount of fruit they eat.

The EPA’s most recent assessment of Phosmet said the chemical shows up at levels of concern in the diets of infants and young children, and blueberries were a major contributor to the estimated exposure. Malathion was classified by the International Agency for Research on Cancer, in 2015, as probably carcinogenic to humans.

Other concerning pesticides are also often found on blueberries:

• Boscalid, a fungicide the EPA classifies as having suggestive evidence of carcinogenic potential, was found on nearly half the blueberries tested, compared to 40 percent in 2014.
• Detections of neonic insecticides have gone up. Acetamiprid and imidacloprid were found on 36 and 12 percent of samples, compared to 11 and 7 percent in 2014. The pyrethroid insecticides cypermethrin and bifenthrin were found on 23 and 16 percent of samples, compared to 21 and 8 percent in 2014. These insecticides are less toxic than the organophosphates they replaced, but recent studies suggest they may also be harmful to children’s health. Additionally, neonic insecticides are very harmful to bees.

We recommend that if you purchase conventional (non-organic) blueberries that you wash them before consuming. At GreenTree we do our best to only source and stock organic blueberries.