Spinach is packed with nutrients – and pesticides, including at least one banned in the EU
Spinach is a nutrient-rich vegetable, making it a staple for healthy eating. But it also has more pesticide residues by weight than any other type of produce – three-fourths of non-organic, or conventional samples are contaminated with a neurotoxic insecticide, permethrin, which is banned from use on food crops in Europe.
Based on latest tests by the Department of Agriculture, spinach ranks second on our Dirty Dozen™ list of fruits and vegetables with the most pesticides.
The USDA’s most recent spinach tests, conducted in 2016, showed a sharp increase in pesticide residues on conventionally grown spinach since the crop was previously tested, in 2008 and 2009.
The USDA published results of a pesticide analysis for 642 conventional spinach samples collected in 2016.
The tests detected an average of seven pesticides on conventional spinach samples, with up to 19 different pesticides or breakdown products on a single sample.
Four pesticides – one insecticide and three fungicides – were responsible for the bulk of the residues detected on spinach.
Seventy-six percent of the samples contained residues of permethrin, a neurotoxic insecticide. Since 2000, Europe has not permitted any permethrin to be used on food crops.
At high doses, permethrin overwhelms the nervous system and causes tremors and seizures.
But several studies have also found a link between lower-level exposure to permethrin-type insecticides and neurological effects in children. In one study, children with detectable permethrin residues in their urine were twice as likely to be diagnosed with ADHD as those with undetectable levels of the pesticide.
Besides its use as a pesticide, permethrin is also used to kill head lice and is embedded in mosquito-repellent fabrics, which can also contribute to children’s exposure.
When the Environmental Protection Agency was assessing the health risks of permethrin and related pesticides on food, EWG wrote to the agency, urging it to consider potential risks to children’s brain development.
Three other fungicides – mandipropamid, fluopicolide and ametoctradin, which are used to kill mold and mildew – were found on spinach samples at relatively high concentrations. Little science has explored the potential human health risks of these chemicals.
Most of the pesticides found on conventional spinach samples are sanctioned as legal and safe by the EPA.
In 2016, 16 of 707 samples had concentrations that violated the EPA’s maximum pesticide residue limits. The USDA also found 83 samples with residues of pesticides that are prohibited for use on spinach but legal on other food crops.
Residues of DDT – a pesticide banned in the 1970s – and its breakdown products remain in the soil and were found on 40 percent of spinach samples. DDT breakdown products were detected in much lower concentrations than the other spinach pesticides but are far more toxic to people.
About EWG’s Shopper’s Guide to Pesticides in Produce
EWG's Shopper’s Guide to Pesticides in Produce is a suite of materials investigating the presence of pesticides in foods and the ways they could harm people, especially children – and to help consumers make the best, most informed choices for their families.
We’ve published the guide nearly every year since 2004.
EWG's Shopper’s Guide is designed to support people who would like to minimize their exposure to pesticides. It includes two well-known lists: the Dirty Dozen, or the 12 fresh non-organic, or conventional, fruits and vegetables with the highest pesticide residues, as well as the Clean Fifteen, the conventionally grown fruits and vegetables with very low or no traces of pesticides.
Some pesticides have more data linking them to health concerns than others. These pesticides are particularly concerning for children, who are especially susceptible to many of the health harms associated with pesticide exposure.
The presence of so many different pesticides in foods is also problematic. There’s little data available about how multiple pesticides interact with each other in the body or how such mixtures could compound each chemical’s individual potential health harms. But the data we do have suggests that when chemicals are present in a mixture, they may be toxic to humans at lower levels than when alone.
When regulating pesticides, government bodies also consider them only one at a time. They don’t look at the potential total body burden for consumers.
