Scientific challenge: 

With new chemicals constantly being used in agriculture, industry and everyday life, research is needed to understand the impact that new chemicals and combinations of chemicals are having on our ecosystems, and the animals and plants that depend on them. This research will inform the regulatory approach to the use of chemicals.

Tractor spraying insecticide

Project overview: 

ChemPop is a four-year NERC-funded project which began in September 2018. It addresses the following research questions:

  • What are the impacts of hazardous chemicals on populations, ecosystems and ecosystem services?
  • What is their relation to other pressures in the environment?

We will address these by mining Britain's extensive wildlife monitoring databases, some of which date back more than 40 years.

Traditional chemical risk assessment has relied on laboratory ecotoxicity studies and, then, modelling (in effect, speculating) what the population or ecosystem functioning consequences might be. We will move beyond these current limitations by interrogating wildlife population data in the terrestrial, freshwater and marine spheres in the context of chemical exposure to help move the subject further forward.

Our high-level aim is to identify which populations and environments are doing well under the current chemical regime and which are not. This will allow the UK to focus its research where the greatest wildlife declines are occurring. 

This should bring clarity to the issue of chemicals in the environment that continues to provoke great anxiety and uncertainty.

Map showing location of macroinvertebrate long-term monitoring sites in England and Wales
Location around UK of stranded cetaceans of different species


The primary duty of the ChemPop project is to identify if and where chemicals have impacted wildlife populations over the period monitored. To do this we have set our tests out on the attached document [PDF] as null hypotheses and our answer to these tests will be ascribed a level of statistical significance.

To ensure we are not being misled, we will also review the impacts on biodiversity or population number over time with other relevant variables for which we have data.

We will examine a wide range of chemical exposures, including pesticides, in the terrestrial and freshwater environments, the de facto chemical mixture in wastewater effluent, rodenticides on land and persistent organic pollutants in the marine environment.


  • Sparrowhawks and rodenticides (body burden) - Lee Walker (UKCEH)
  • Invertebrates, including predatory beetles, arable area spiders, hoverflies, butterflies and moths and predicted pesticide exposure - Ben Woodcock and Nick Isaac (UKCEH)


Marine waters

  • Cetaceans and exposure from POPs identified by body burden - Rosie Williams (ZSL)

Ecosystems services impact

  • If and where chemicals harm species and taxa that are providers of ecosystem services or represent native biodiversity identified by the public as important then these impacts will be assessed - Ben Woodcock (UKCEH)

The relationship between population outcomes and regulation

  • To review whether our current regulation is over or under protective and to rank chemicals against non-chemical stressors in importance to wildlife - John Sumpter and Tamsin Runnalls (Brunel University)

 We will ask: how important are chemical stressors in relation to other pressures in the environment?

By comparing long-term and spatially explicit trends in natural populations, with the response predicted by classical ecotoxicity as reported in the literature, we will evaluate whether such tests are indicative of impacts in the wild. This is essential to assess to what extent traditional risk assessments, typical of those used in the Water Framework and similar Directives, are predictive of outcomes for wildlife populations in terrestrial, freshwater or marine environments.


Background to the research and an update on work to date on terrestrial invertebrates (April 2021)


Freshwater environment progress report (April 2021)

Marine environment progress report (April 2021)



  • Natural Environment Research Council