Systemic Pesticides: Chemicals You Can’t Wash Off

Washing or peeling fruits and vegetables won’t protect you from systemic pesticides spread throughout the plant's tissues.

| October/November 2010

systemic pesticides

Systemic pesticides are in the plant, not on it. When we make the plant itself poisonous to predators, one has to wonder what (or who) else it’s poisoning.


In conventional food production systems, not all pesticides remain on a plant’s exterior. Systemic pesticides are chemicals that are actually absorbed by a plant when applied to seeds, soil, or leaves. The chemicals then circulate through the plant’s tissues, killing the insects that feed on them. Use of these pesticides on food crops began in 1998, and has steadily increased during the past 10 years. Unlike with traditional insecticides, you can’t wash or peel off systemic pesticide residues.

The four main systemics used on food crops (listed below) are members of the nitroguanidine/neonicotinoid group of chemicals, which has been implicated in the mysterious colony collapse disorder that has killed millions of bees. (See our article Colony Collapse: Are Potent Pesticides Killing Honeybees?)

Imidacloprid can be applied to many vegetables (including tomatoes and leafy greens) right up to the day they’re harvested.

Thiamethoxam was first approved as a seed treatment for corn in 2002, and thiamethoxam products that are applied to the soil have since been approved for use on most vegetable and fruit crops. 

Clothianidin is used as a seed treatment on canola, cereals, corn and sugar beets, and as a soil treatment for potatoes.

Dinotefuran can be applied to soil or sprayed on leafy greens, potatoes, and cucumber family crops.

8/14/2017 6:33:38 PM

It's amazing that the media does not cover this issue or perhaps does not know about it. 20 years ago I heard about third world countries growing fruit were pouring pesticides at the root of the trees and it was absorbed into the fruit. But, I have heard nothing since. Except of course, that all the bees were dying because of 'unknown' reasons.

Mary Rowlands
10/7/2013 9:05:30 PM

here's a thought. do you suppose organic farmers escape collateral damage when they aerial spray for mosquitos, etc?

Irene Tukapua
4/24/2012 4:28:17 PM

What a pack of F%#@@$%^&((()*&^$z who are making important decisions for the whole entire human race, what is the agenda besides utter complete greed by these drug companies and bought and paid for cronies who pass the legislation to allow such a travesty to exist......just goes back to the old saying that money is the root of all evil.........

Rosalie Learmont_2
10/12/2010 7:04:13 PM

Excellent article. As many people as possible need to read it. The big game of chemical pesticide mixes being concocted to replace the ones currently allowed until the "testing" rules them out, is a revolving door of toxic pile-up, consumption, and selling off supplies to other countries who haven't finished their "testing". Now this article awakens me to how the manufacturers feel its ok to make a chemical pesticide that openly states it is systemic and cannot be washed off. And partner to these manufacturers is the EPA, who thinks it can get this by people without everyone knowing the EPA cannot care about human life or wildlife and fauna. I will search for an organization addressing the EPA about this kind of chemical use in our food system. Its time for the food system to get an overhaul.

mother earth news fair


Feb. 17-18, 2018
Belton, Texas

More than 150 workshops, great deals from more than 200 exhibitors, off-stage demos, hands-on workshops, and great food!