Global review warns of hidden health and ecological risks from widely used strobilurin fungicides

Strobilurin farm fungicides are showing up from wheat fields to pregnant womens urine, and a new scientific review warns that these “modern” crop protectants may carry hidden risks for ecosystems and human health.

What the study found

The paper reviews global data on a widely used class of fungicides called strobilurins, which have been sprayed on crops worldwide since the 1990s to prevent fungal diseases in plants such as wheat, rice, grapes, apples, and bananas. These chemicals are popular because they are effective at low doses and were long thought to be relatively safe for humans and other mammals.​

Yet the review shows that residues of strobilurin fungicides are now detected almost everywhere scientists look, including food, rivers and lakes, indoor dust, and even human blood and urine. The authors argue that this emerging pattern points to a global contamination issue that regulators and the public can no longer ignore.​

“In just a few decades, strobilurins have gone from laboratory innovation to a silent, worldwide presence in our food, water, and bodies,” said lead author Dr Jingchuan Xue of Guangdong University of Technology. “Our review shows that we must update how we assess their risks in real world conditions, not just in controlled lab tests”.​

Ubiquitous exposure from farm to home

The review compiles monitoring results from multiple countries and environmental media. Key findings include:​

• Residues on major crops
  Strobilurin compounds such as azoxystrobin and pyraclostrobin are routinely found on staple foods including wheat, corn, peppers, apples, tea, grapes, and bananas, sometimes at milligram per kilogram levels in field studies from China, Brazil, Turkey, and other regions.​

• Contamination of water and soil
  These fungicides have been detected in agricultural soils, sediments, streams, rivers, groundwater, and even treated drinking water, with concentrations in some surface waters reaching tens to hundreds of nanograms per liter or higher in heavily farmed areas.​

• Indoors and in human bodies
  Strobilurin residues occur in household dust in several Chinese cities, and azoxystrobin metabolites have been found in 100 percent of urine samples from a cohort of 3421 pregnant women in France, as well as in pregnant women and children in China at low nanogram per milliliter levels.​

Together, these data suggest that people are exposed through food, drinking water, house dust, and direct contact during agricultural work, with children and pregnant women among the most vulnerable groups.​

How these fungicides affect living cells

Strobilurins are designed to kill fungi by disrupting energy production in their mitochondria, sometimes called the “powerhouses” of the cell. The review highlights growing evidence that this same mode of action can harm non target organisms.​

• Mitochondrial damage
  In zebrafish embryos, commonly used strobilurins such as pyraclostrobin, trifloxystrobin, and azoxystrobin can reduce oxygen consumption and ATP production by up to 98 percent at high test concentrations, indicating severe mitochondrial dysfunction and energy failure.​

• Oxidative stress and DNA damage
  Multiple studies in fish, algae, earthworms, and mammalian cells show that strobilurins increase reactive oxygen species, overwhelm antioxidant defenses, and damage DNA, sometimes even at concentrations closer to those measured in the environment.​

• Endocrine and developmental effects
  At low microgram per liter levels, some strobilurins interfere with hormone signaling, reduce reproduction in aquatic invertebrates, and cause malformations such as heart defects, delayed hatching, and abnormal growth in fish embryos.​

• Potential neurotoxicity
  Experiments with mouse neurons suggest that several strobilurins can trigger patterns of gene expression linked to brain aging and neurological diseases, and can kill neurons through calcium overload and mitochondrial collapse.​

Although some experimental doses are higher than typical environmental levels, the authors stress that wildlife and people are often exposed to mixtures of several fungicides over long periods, a scenario that is rarely tested in standard safety assessments.​

A complex environmental fate, but slow policy response

Once released, strobilurin fungicides can be transformed by sunlight and water chemistry, or broken down by microbes, but some compounds still persist long enough to travel through soils, rivers, and the atmosphere. Microorganisms are able to use several strobilurins as a carbon source, and the review identifies specific bacterial strains that can rapidly degrade these chemicals, pointing to future options for bioremediation technologies.​

Despite this progress in understanding their chemistry and toxicology, regulatory limits remain patchy and incomplete. Tolerable daily intake values are missing for many strobilurins, and large scale biomonitoring of general populations has only begun in a few countries, making it difficult to fully quantify health risks for the public.​

Call for global monitoring and smarter models

To close these gaps, the authors recommend a coordinated international effort that combines better environmental surveillance with advanced computational tools. They highlight three urgent needs:​

• Expanded monitoring of air, drinking water, dust, and consumer products, especially in regions with intensive pesticide use and among sensitive populations such as children and pregnant women.​

• Mechanistic studies using modern omics approaches to map how strobilurins disrupt biological pathways beyond mitochondria, including immune function, endocrine systems, and epigenetic regulation.​

• Predictive models that link chemical structure to toxicity and simulate realistic exposure scenarios, including mixtures of multiple fungicides, to guide regulation and safer product design.​

“Strobilurin fungicides are a success story for crop protection, but their unintended consequences are now becoming visible across ecosystems and human populations,” said co author Dr Zhilei Liu. “Stronger monitoring and smarter risk assessment tools can help us protect both food security and long term health”.​

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Journal reference: Liu Z, Liu Y, Zhang H, Zhao Y, Zhang T, et al. 2025. A brief review of strobilurin fungicides: environmental exposure, transformation, and toxicity. New Contaminants 1: e004  

https://www.maxapress.com/article/doi/10.48130/newcontam-0025-0002  

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About the Journal:

New Contaminants is an open-access journal focusing on research related to emerging pollutants and their remediation.

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