Chemicals in the Environment

Our central theme of work is on the sources, pathways and risks associated with emerging and legacy chemicals of global concern. This includes human and veterinary pharmaceuticals, with environmental health impacts already demonstrated for currently measured exposure concentrations. Our group has successfully identified an environmental pathway for the complete breakdown of a major class of prescribed pharmaceuticals (the benzodiazepines) known to affect fish behaviour and thus pose a risk to aquatic ecosystems. Working with AstraZeneca more recently we have concentrated on understanding pharmaceutical exposure pathways via sorption and biodegradation in the soils and wastewater of low to middle income countries. This is essential in order to understand environmental risks associated with increased use of medicines in Africa and similar regions. Our work on medicines also relates to the environmental risks of pandemics, including antiviral drugs and antibiotics required to treat secondary bacterial infections in patients.

Our group is working to understand the issues associated with climate change and farming with respect to the comparative environmental risks of fungicides versus fungal toxins (mycotoxins). Funded by NERC, our pioneering work has shown that mycotoxins associated with warmer winters in the UK can have impacts on aquatic plants and animals. Some of these mycotoxins are also endocrine disrupters, with significant implications for the reproductive health of fish and other wildlife. Working with Natural England and the RSPB, we are assessing nutrient release from farming and water quality impacts within internationally important Ramsar wetlands. Our research to support sustainable farming also extends to Africa, where we are studying the use of copper fungicides and soil health in co-operation with the Nelson Mandela African Institution of Science and Technology, Tanzania.

We study environmental exposures and risks of legacy pollutants, such as metals and Persistent Organic Pollutants (POPs), in freshwater and marine environments. Linking to the Stockholm Convention and related international legislation, we are working to understand exposure pathways in marine ecosystems, including dietary and waterborne exposure pathways (e.g. endocrine disrupters, flame-retardants and microplastics). Building on our expertise in contaminated land assessments, we address the toxicity of metals used in nanomaterials on soil organisms such as earthworms. Our collective skills in environmental chemistry, modelling, toxicology and risk assessment ensures that we are ideally placed to address future emerging chemical risks in freshwater, marine and terrestrial environments.

Some of our focus is aimed at the identification of emerging pollutants. This includes work on plastics and plastics additives in collaboration with the International Marine Litter Research Unit, taking advantage of our analytical chemistry laboratories and consolidated radioisotope facility. The NERC MINIMISE project uses cutting edge technologies to deliver new knowledge of the risks posed by microplastics, aiming to work towards solutions, and support informed choices about the sustainable use of plastic and associated contaminants. Other emerging pollutants of interest are chemicals derived from oil production, such as oil sands or marine platforms. Regulatory authorities classify substances discharged to the marine environment according to environmental risk, however, the presence of unknown components with uncharacterized and potential long-term toxicity is not covered. In the PW-Exposed project, we use our instrumentation for high resolution accurate mass-Orbitrap mass spectrometry in order to characterise these compounds and assist ecotoxicological risk assessments.