Spinach is packed with nutrients – but also EU-banned pesticides

WEDNESDAY, MARCH 20, 2019

Spinach is packed with nutrients, making it a staple for healthy eating. But federal data show that non-organic spinach has more pesticide residues by weight than all other produce tested, with three-fourths of samples tested contaminated with a neurotoxic bug killer banned from use on food crops in Europe.

The latest tests by the Department of Agriculture, in 2015 and 2016, showed a sharp increase in pesticide residues on conventionally grown spinach since the crop was last tested, in 2008 and 2009. Based on the USDA tests, spinach ranks second on our Dirty Dozen™ list of fruits and vegetables with the most pesticides – a significant jump from its previous rank of eighth.

The USDA recently published results of a pesticide analysis for 642 conventional spinach samples collected in 2016. They contained far more pesticides by weight than all other crops tested, and double or more the amount found on all other Dirty Dozen crops.

The tests detected an average of 7.1 pesticides on every conventional spinach sample collected in 2016, with a maximum of 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. At high doses, permethrin overwhelms the nervous system and causes tremors and seizures.

But several studies also find 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 children with non-detectable 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. While 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. Since 2000, Europe has not permitted any permethrin to be used on food crops.

Three other fungicides – mandipropam, fluopicolide and ametoctradin, which are used to kill mold and mildew – were found on spinach samples at relatively high concentrations.

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 found 83 samples with residues of pesticides that are prohibited for use on spinach but legal on other food crops. Nearly all were grown in the U.S.

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 and very few other crops. DDT breakdown products were detected in much lower concentrations than the other spinach pesticides but are far more toxic to people.

Spinach sold in U.S. grocery stores is mostly grown domestically, with approximately 65 percent coming from California. Spinach from Arizona, New Jersey and Texas and foreign imports make up the rest.

Consumer Tips

• Eat lots of vegetables and fruits. Spinach is a great source of vitamin A, folate and vitamin C. It’s also a good source of vitamin E and potassium.
• Buy organic spinach and other leafy greens, if you can.
• Wash spinach thoroughly. California tests of unwashed spinach found higher concentrations of pesticides. The USDA washed all of the spinach samples vigorously before testing. The USDA has also detected pesticides on frozen and canned spinach, suggesting that washing and cooking reduces but does not eliminate pesticide levels.