(Beyond Pesticides, June 26, 2025) A review article in Nature Reviews Earth & Environment highlights how the pesticides used in global crop production pose risks to ecosystems and human health through multiple pathways. As the authors note, “Once applied to crops, pesticides are transported through surface and groundwater flows, atmospheric dispersion and wildlife migration.” Residues in food products, such as fruits and vegetables, as well as bioaccumulation within animals that are consumed as food, also threaten consumers around the world, particularly those relying on international trade.

The researchers note: “In this Review, we summarize the pathways through which synthetic pesticides transcend boundaries, focusing on the impacts of their use in food production… First, we explain how environmental flows contribute to transporting pesticides to regions far from their original source. Next, we examine the role of international food trade in causing transboundary exposure and impact of pesticide use.” As a result, the study calls for prioritizing biodiversity and human health through sustainable methods while maintaining yield to support the growing population.

The use of pesticides in chemical-intensive agriculture has exponentially increased since their first synthesis in the late 1930s. “Globally, pesticides were applied on agricultural land at an average rate of 2.4 kg per hectare (kg ha-1) in 2022, nearly double the rate in 1990,” the authors explain. “About 40% of countries exceeded the global average rate in 2022, with pesticide use volumes in low-income countries growing more than 150% between 2008 and 2018.”

As the researchers point out, and has been documented in scientific literature for decades, “human exposure to pesticides, either occupational or environmental (via air, drinking water and food), can lead to cancers, neurological disorders, respiratory disorders and endocrine disruptions.” (See studies here, here, here, and here, as well as Beyond Pesticides’ extensive coverage of these health effects in the Pesticide-Induced Diseases Database.)

They continue: “Pollinator exposure to pesticides can impair their detoxification mechanisms and immune responses, increasing their vulnerability to other environmental stresses. Pesticide use has also been associated to the decline of bird population, stream invertebrates, and abundance and diversity of soil fauna. Subsequent decreases in biodiversity negatively impact the ecosystem functions necessary for sustaining crop production.” (See more on pesticides’ effect on ecosystems here and here.)

Pesticides impact not only local populations and ecosystems but can have implications in surrounding areas, as well as across international boundaries. “After being released to the environment, pesticides undergo various biotic and abiotic processes at rates dependent on their physicochemical properties and environmental conditions,” the study says. “Of the pesticide mass applied globally, approximately 82% is degraded to daughter molecules, some of which potentially retain toxicity to non-target organisms.” (See studies here and here.)

The authors further explain, noting: “The undegraded pesticides and their transformation products move through and accumulate in soil, groundwater, surface waters and atmosphere via various transport pathways. Such pathways include wind drifts, infiltration into soils and leaching to groundwater, surface run-offs and soil erosion, and can transcend boundaries.”

One study identifies a potential transboundary transport of pesticides involving the Tijuana River watershed, as two pesticides (methidathion and mevinphos), both banned in the U.S. but not in Mexico, were detected in rivers within the U.S. boundaries. “The presence of pesticides in the atmosphere and their long-distance travel can lead to exposure of local and adjacent biodiversity and communities, as well as damage to non-target crops,” the researchers state. (See studies here and here.)

Beyond Pesticides recently shared in the Daily News that, for the first time, 15 currently used pesticides (CUPs) and four metabolites (breakdown or transformation products—TP) were found in the marine atmosphere over the Atlantic Ocean. Three legacy (banned) pesticides were also discovered. According to the study, published in Environmental Pollution, researchers found empirical evidence for pesticide drift over remarkably long distances to remote environments.

“Drifting pesticide droplets often deposit into surface waters, leading to biodiversity and communities far from application points being exposed to pesticides through contaminated water,” the researchers share. “For example, atmospheric exchange of chemicals (including pesticides) in Lake Michigan, in the Great Lakes region in the USA, is one order of magnitude greater than that of chemicals transported directly into the lake from its tributaries.” (See studies here and here.)

Pesticide drift threatens human health near and far from the point of application. Another study shows how “high numbers of pesticide residues are found in indoor dust in Europe and Argentina, even in areas far from agricultural fields, highlighting the importance of atmospheric drift as a transport pathway.” Impacts on nearby crops is also important, as “dicamba pre-emergence applications on herbicide-tolerant crops causes an average damage of 4% (up to 8%) to off-target soybean fields in the USA,” the study authors say.

Additionally, bioaccumulation and biomagnification can occur with cascading impacts on organisms. Studies highlight the particular prevalence of this in aquatic ecosystems, as pesticides can easily move through multiple trophic levels, such as from plankton to fish and predators.

“Wildlife migration is another pathway for long-range transboundary pesticide transport,” the researchers point out. They continue, “Contaminated wildlife that migrate seasonally or periodically across habitats far from agricultural fields, with some having habitats spanning across multiple countries and regions, can cause exposure of predators and humans in distal regions through hunting or consumption.”

Pesticide residues also remain on crops that are consumed by both humans and livestock, which further threatens consumers through dietary intake. “With international food trade, these pesticide residues can be transported across national boundaries, exposing consumers in importing countries to pesticides,” the study says.

The horticultural products that most frequently contain pesticide residues include fruits, vegetables, nuts, and legumes. “About 62–76% of sampled horticultural products produced in the USA, China and the EU [European Union] bear one or more synthetic pesticide residue,” the authors share. (See research here, here, here, and here.)

They continue, saying: “In Western countries, citrus fruit, berries, pulses and leafy vegetables are generally among the most pesticide-tainted foods, with 85% of harvested produce containing pesticide residues… Conventionally grown foods generally exhibit a fourfold higher prevalence of pesticide residues than organic produce.”

As previously reported by Beyond Pesticides, adopting a fully organic diet can reduce pesticide levels in urine within just two weeks “by an average of 98.6%” and facilitate faster DNA damage repair relative to a diet of food grown with chemical-intensive practices, according to findings from a randomized clinical trial published in Nutrire. The authors explain that their finding “is likely due to two main factors: the presence of compounds characteristic of [an organic] diet, which may have high levels of antioxidants that can protect DNA and also induce DNA repair [], and the absence or decrease in the incidence of pesticides in this type of diet, which are recognized for their genotoxic effects and have the ability to affect the genetic repair system of organisms [].” (See additional coverage on the benefits of an organic diet here.)

One of the main issues that the study highlights is the inconsistency of maximum residue level (MRL) compliance across the globe. “Furthermore, chronic exposure to residues below MRL levels can lead to health problems such as non-Hodgkin lymphoma, obesity or reproductive disorders,” the researchers state.

They continue: “The presence of pesticide residues raises substantial food safety concerns, not only for local consumers but also for those in importing countries. Countries with stringent pesticide regulations, such as the EU, might experience low rates of MRL violations in domestically produced foods, but imported foods often exhibit much higher violation rates.”

The alternative, that prevents these health and environmental risks, lies in organic land management. As the authors summarize, “Pesticide pollution can be resolved through large-scale adoption of agroecological and biodiversity-driven management solutions, which can simultaneously support yields and ecosystem services.”

A transition to organic agriculture eliminates the use of petrochemical pesticides and synthetic fertilizers while prioritizing soil health, protecting and enhancing biodiversity, safeguarding public health, and mitigating climate change.

Learn more about the health and environmental benefits of organic here and here. Take action to support the advancement of organic, sustainable, and regenerative practices and policies, and get your community involved through the Parks for a Sustainable Future program.

All unattributed positions and opinions in this piece are those of Beyond Pesticides.

Source:

Tang, F. et al. (2025) Transboundary impacts of pesticide use in food production, Nature Reviews Earth & Environment. Available at: https://www.nature.com/articles/s43017-025-00673-y.