Can We Protect Crops While Saving Our Ecosystems?
August 20, 2025
Imagine a silent revolution happening in the fields around us. Every growing season, thousands of chemical formulations are deployed to protect our crops from pests and diseases, ensuring food security for millions. Yet, these same protectors may be contributing to the alarming decline of biodiversity worldwide—from the humble earthworm beneath our feet to the bees pollinating our orchards and the birds singing in the sky.
This paradox lies at the heart of one of today's most pressing environmental challenges: how do we regulate plant protection products (PPPs) to safeguard both our food supply and the natural world upon which it ultimately depends?
The European Union has developed what many consider the world's most stringent regulatory system for PPPs, yet biodiversity continues to decline in agricultural areas 1 2 . This article explores the complex scientific and regulatory landscape governing these essential but potentially harmful substances, examining the strengths and limitations of current approaches, and highlighting the innovative science that might help us build a more sustainable future.
The European regulatory framework for PPPs operates like a sophisticated filtration system, designed to eliminate potentially harmful products before they reach the market. At its core lies a tiered risk assessment process that progresses from basic laboratory studies to complex field experiments when necessary 3 .
Standardized tests on representative species including honeybees, earthworms, and birds to determine acute and chronic toxicity.
Higher-tier evaluations examining effects under realistic conditions to establish thresholds for acceptable risk.
Multiple organizations contribute to this complex evaluation process. The European Food Safety Authority (EFSA) provides scientific opinions and guidance, while national authorities in member states conduct initial assessments. Interestingly, the evaluation processes often involve the manufacturers themselves in generating required data, creating potential conflicts of interest that have drawn criticism from researchers 1 .
The EU regulatory system operates on the precautionary principle, leading to banning of numerous harmful substances 2 .
One of the most significant gaps in current regulation is the inadequate assessment of mixture effects. While individual pesticides may be deemed safe at specific concentrations, farmers typically use multiple products throughout growing seasons. These chemicals can mix in the environment, creating potent combinations that affect ecosystems in ways single-substance testing cannot predict 1 2 .
Perhaps the most alarming limitation is the inadequate assessment of in-field effects on non-target plants and arthropods. Agricultural fields aren't just production zones—they're crucial habitats for numerous specially adapted species. Current regulations focus predominantly on off-field impacts, largely ignoring how pesticides affect biodiversity within treated areas 6 .
A particularly insidious problem is pesticide drift—the phenomenon where a significant portion of applied chemicals (up to 25-60%) moves away from the target area through air currents. This drift can transport pesticides hundreds or even thousands of kilometers, contaminating distant ecosystems 4 .
| Factor | Impact on Drift Potential | Ecological Consequences |
|---|---|---|
| Wind speed | Increased drift with higher winds | Wider contamination distribution |
| Temperature | Higher temperatures increase volatilization | Increased long-range transport |
| Humidity | Lower humidity increases evaporation | Greater particle mobility |
| Soil type | Light soils increase volatilization | Variable local impacts |
| Application technique | Fine sprays drift more readily | Significant technology impact |
In July 2023, a landmark workshop brought together experts from across Europe to address a critical question: Does current pesticide risk assessment adequately protect in-field biodiversity? The gathering included representatives from research institutions, regulatory bodies, and environmental agencies, all concerned about the rapid decline of farmland species 6 .
Participants developed and validated a two-step assessment method to determine whether pesticide products might have severe impacts on plants or arthropods that would subsequently affect the broader food web:
Researchers determined whether a pesticide product causes severe effects on non-target terrestrial plants (NTTPs) or non-target arthropods (NTAs) at expected exposure levels.
For products showing severe effects, researchers evaluated whether these impacts extended across a broad taxonomic spectrum.
The workshop revealed that effects due to in-field exposure are currently not assessed for plants and inadequately assessed for arthropods. This gap results in significant impairment of food web support and biodiversity, contrary to the requirements of EU regulations that mandate protection of non-target species and ecosystem functioning 6 .
| Organism Group | Documented Effects | Conservation Status |
|---|---|---|
| Earthworms | Reduced populations in agricultural soils; impaired reproduction | Declining in intensively farmed areas |
| Pollinators | Acute mortality; navigation impairment; reduced reproduction | 37% of European bee species declining |
| Farmland birds | Reduced food availability; reproductive failure | 57% of species declining in Europe |
| Soil microorganisms | Changes in community composition; reduced diversity | Limited monitoring data available |
| Non-target plants | Drastic reduction in arable plant diversity | 20 species extinct in UK alone |
Understanding pesticide impacts requires sophisticated tools and concepts. Here are some crucial ones that scientists employ:
Intermediate-scale experimental systems that bridge the gap between laboratory studies and real-world ecosystems.
Technique to identify entire communities of organisms by analyzing DNA fragments in environmental samples.
Physiological indicators of exposure or effect measured in organisms.
Labeling pesticide molecules with rare stable isotopes to track their movement through food webs.
| Method | What It Measures | Advantages |
|---|---|---|
| DNA metabarcoding | Microbial and invertebrate diversity through genetic analysis | Comprehensive community assessment; high sensitivity |
| Phospholipid fatty acid (PLFA) analysis | Microbial community structure based on membrane lipids | No need for culturing; community-level assessment |
| Soil Quality TRIAD | Integrated assessment of chemical, ecological, and toxicological parameters | Holistic site evaluation; multiple lines of evidence |
| Microcosm/mesocosm tests | Effects on simplified model ecosystems under controlled conditions | Realistic exposure scenarios; community-level responses |
| Trophic interaction monitoring | Food web complexity and stability through stable isotope analysis | Reveals indirect effects and functional changes |
Combining multiple assessment methods like the Soil Quality TRIAD approach for comprehensive ecosystem evaluation 5 .
Opening the evaluation process to a broader range of stakeholders including beekeepers and farmers 1 .
The future of PPP assessment lies in embracing greater ecological realism. This means moving beyond single-species tests to evaluate impacts on species interactions, food webs, and ecosystem functions. It requires acknowledging that agricultural fields are functioning ecosystems, not just production spaces 5 6 .
The regulatory framework for plant protection products represents a remarkable human endeavor to balance competing needs: productive agriculture versus biodiversity conservation, chemical innovation versus precautionary protection. While the European approach is among the most sophisticated in the world, significant gaps remain between regulatory assessments and real-world ecological impacts.
Addressing these gaps requires acknowledging that agricultural ecosystems are complex, interconnected systems where chemicals can have far-reaching and unexpected effects. The promising developments in assessment methodologies—from sophisticated modeling approaches to innovative monitoring technologies—suggest that we're moving toward more comprehensive protection strategies.
Ultimately, protecting biodiversity while ensuring food security will require more than technical adjustments to risk assessment protocols. It demands a fundamental reconsideration of agricultural systems themselves, promoting practices that work with ecological processes rather than against them. As research continues to reveal the hidden connections between plant protection products and ecosystem health, we have an opportunity to create a regulatory system that truly safeguards the wondrous web of life that sustains us all.
The journey toward truly sustainable agriculture continues, with science as our guide and responsibility as our compass.