Pesticides 'of all types' damage soil life

Researchers have found comprehensive evidence that pesticides directly harm soil life and the ecosystems it preserves.

Pesticides of all types pose a clear risk to organisms living in soil and that play a key role in food sustainability and carbon storage, a major new report has found.

Researchers in the US reviewed 400 different studies, looking at 275 unique species and 284 different pesticides, to place new emphasis on the impact of these chemicals on soil.

The results, published this week in the journal Frontiers in Environmental Science, found that “pesticides of all types pose a clear hazard to soil invertebrates. Negative effects are evident in both lab and field studies, across all studied pesticide classes, and in a wide variety of soil organisms.”

Previous work on the impact of pesticides has focused on water and air, as runoff and pesticide drift are the most significant sources of offsite pesticide movement, researchers said.

But pesticides are often applied directly to soil as drenches and granules, and increasingly in the form of seed coatings, making it important to understand how pesticides impact soil ecosystems.

Burrowing by worms aerates soil and allows it to retain water, air and nutrients. Image Flickr/Meaduva.

Soil is home to some of the most complex biodiversity on Earth, with a typical sample comprising hundreds of thousands of macroinvertebrates and nematodes, as well as microorganisms, and bacterial species.

“Soils contain an abundance of biologically diverse organisms that perform many important functions such as nutrient cycling, soil structure maintenance, carbon transformation, and the regulation of pests and diseases,” the researchers wrote.

Soil biodiversity helps these ecosystem functions continue, while burrowing activity aerates soil and increases water retention. Earthworms alone can construct up to 8,900 km of channels per hectare, decreasing soil erosion by 50 per cent via increased soil porosity and water infiltration, the study said.

Researchers concluded that the prevalence of negative effects highlights how soil and soil life should be considered within any risk assessment for pesticides.


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  1. Its like we don’t say eating animals we call it meat! It hides the thing we are doing. In the same way we call them pesticides not poisons! Who needs numerous studies to show what is obvious. When we try to harm one part of nature we harm it all, including us!

    1. Hi Anthony, a good point – do you think that if ingredients had to list on the label what pesticides go into the food we eat (including herbicides, mould inhibitors etc…) that awareness of these toxic substances being part of the food chain would grow, changing buying habits?

    1. A reminder is no bad thing! As soil is the forgotten crucial base our food system rests on. It is good that in a world where we need to prove scientifically nature knows best, research is backing this up.

    2. I’m sure that is right. But also, because a lot of people won’t have read the old classics like Small is Beautiful and Silent Spring, it might be worth you while to let us have a list of farm-based books of that nature which would give us all a basic background. Juliet Solomon

  2. I am aware that the whole question of ingredients labelling is complicated. The makers of various products, I think, want to keep people in the dark as much as possible! Many do not want to label GM material in food. Also manufacturers claim pesticides and other poisons are all at ‘safe’ levels. But as Guy has pointed out, his farming career has been littered by chemicals we were told to be safe, later to be banned. I suppose one of the latest would be glyphosate.

    Some want highly processed meat products to come with a health warning like cigarettes! Is that a bit extreme? I suppose it depends on your point of view.

    I wonder if its similar to products, at the moment, saying ‘this may contain traces of milk and eggs’. Perhaps they should also say this product may contain traces of pesticides or other harmful chemicals. I know I’ve rambled but these are some of my thoughts.

    1. The idea of ‘safe’ levels of synthetic pesticides is misleading as their cumulative effect, what happens when you combine different ones in tiny quantities over time, is not yet fully understood. The bottom line feels like we shouldn’t be putting vast quantities of pesticides on what we eat when we can grow in a way that will nourish rather than deplete the soils, expand rather than reduce biodiversity, and enjoy healthy organic food instead.

  3. I think it’s time that organic vegetables should be loose /packaging free and subsidised, and it should be the vegetables grown with chemicals in the plastic bags labelled with what pesticides etc have been used. I think it is the only way things will change for the better at a fast enough rate.


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