Pesticides a major contributor to global biodiversity crisis, says study

A comprehensive new study has shown that pesticides are a major contributor to the global biodiversity crisis.

The research has highlighted overwhelming negative impacts for more than 800 species of plants, animals, fungi and microbes that they are not intended to harm.

It was discovered that chemicals used in farms, businesses and homes reduce species' ability to reproduce, grow or function.

A wide range of wildlife is impact by the routine use of pesticides and herbicides on agricultural land (Alan Jack).

Grim findings

The findings come from the first study assessing the impacts of pesticides across all types of species in land and water habitats, carried out by an international research team that included the UK Centre for Ecology and Hydrology (UKCEH) and the University of Sussex.

Scientists analysed more than 1,700 existing lab and field studies of the impacts of 471 different pesticide types – either insecticides, fungicides or herbicides – in agricultural, commercial or domestic use.

 Wide-ranging negative effects were seen for more than 800 species found on land and in water, including impacts on how fast they grow, their reproductive success and even behaviour such as their ability to catch prey, find plants to forage upon, move or attract mates. Pesticides can also affect organisms' metabolism and damage cells.

These negative effects can result in the premature death of wild organisms and reduce populations.

Wide-ranging research

The international study, led by East China University of Science and Technology, has been published open-access in Nature Communications.

The researchers say that, unlike previous studies which have tended to look at specific groups of species such as bees, fish or plants, or specific habitats, they have considered representatives of the whole spectrum of species found in the natural world.

"Our study provides an unparalleled insight into the consequences of pesticide use on the natural environment globally," said co-author Dr Ben Woodcock, an ecologist at UKCEH.

"Pesticides are a necessary evil, without which global food production and farmers' livelihoods would likely collapse. However, our findings highlight the need for policies and practices to reduce their use.

"This could include bottom-up initiatives led by farmers such as regenerative agriculture, as well as government policies such as DEFRA's Sustainable Farming Incentive, which pays farmers to reduce insecticide use on crops."

Professor Dave Goulson of the University of Sussex, who was also part of the research, added: "It is often assumed that pesticides are toxic primarily to the target pest and closely related organisms, but this is clearly not true. Concerningly, we found pervasive negative impacts across plants, animals, fungi and microbes, threatening the integrity of ecosystems."

The research shows that it is not just groups of insects that are being negatively impacted (Chris Teague).

What are the alternatives?

Overuse of pesticides not only threatens beneficial species they are not intended to target but can also enable pests to develop resistance to the chemicals, rendering them ineffective. Farms in the UK, for example, are currently encouraged to carry out an Integrated Pest Management assessment which emphasises reduced pesticide use and natural pest control. In the EU, more than 10% of land under agricultural production is organic, using no synthetic pesticides.

Alternative options for farmers include planting wildflowers and beetle banks to support species that eat pests, allowing them to reduce spraying when there are high numbers of these natural predators present. Other measures include adjusting the timing of planting to avoid pests and rotating crops to break the species' life cycles and reduce their numbers.

Gardeners can do their bit to reduce the use of chemicals. Options for natural pest control include introducing nematodes, ladybirds or mites, which can be bought online, and encouraging other natural predators such as frogs, birds and hedgehogs with wildlife-friendly gardening. Physical barriers such as netting can prevent caterpillar and bird damage.

Future plans

New monitoring work by UKCEH, working with DEFRA, is currently using honeybee colonies to monitor pesticide risks across England to act as an early warning of emerging problems.

Dr Woodcock pointed out there was a lot of scope in the future for developing agricultural methods to be more responsive to our natural pest controllers, such as AI monitoring of both pests and predators using high-tech cameras.

Reference

Wan, N-F, et al. 2025. Pesticides have negative effects on non-target organisms. Nature Communications. DOI: 10.1038/s41467-025-56732-x.