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Assessing and Managing the Impacts of Climate Change on the Environmental Risks of Agricultural Pathogens and Contaminants - SD0441

Climate change models predict that average temperatures will increase by up to 5 °C by the 2080s, that winters will be wetter, summers will be drier and that there will be an increase in the number of intense rain events (UKCIP2002).

Researchers have recognised that these changes are likely to have important impacts on the prevalence and types of plant and animal disease across the UK and on chemical usage. For example, long periods of rain on farms are likely to cause puddles and general surface water to collect, resulting in increased transmission of bacterial pathogens. Intense rain events may also result in localised flooding of farming areas, increasing the likelihood of sewage stores, slurry pits and tanks overflowing. This could provide an additional and widespread transfer mechanism to contaminate pasture and other areas where livestock have access with zoonotic agents present in faecal material. Shifts in temperature will have both positive and negative effects on animal and food borne pathogens. Whilst some pathogens will survive in certain environments with increased temperatures, for example E. coli O157 in water contaminated with faeces (Cumby et al., 2003), others may be adversely affected, for example Campylobacter in water (ICMSF, 1996) and exotic viruses such as Foot and Mouth Disease and Classical Swine Fever outside of the host.

Climate change is likely to have profound effects on the pests and diseases of the crops grown in the UK and may also affect the distribution of the crops themselves. Again, these effects could be both positive and negative, depending upon the organism. These in turn will have a major impact upon the chemical use and associated contamination of agricultural land and watercourses.

Changes in climate are also likely to affect soil properties (e.g. Defra Project SP0538) as well as the fate and transport of pathogens and chemical contaminants in the UK environment (e.g. Defra Projects PS2208, CC0375). Increased temperatures may well enhance the degradation of chemicals contaminants in environmental matrices and increases in rainfall intensity may increase the transport of chemicals and pathogens from the soil surface to groundwaters and surface waters.

The future risks of pathogens and contaminants to agricultural systems and the rural environment could therefore be very different from current risks. There is therefore an urgent need to establish the impacts of climate change on the risks posed by chemical and microbial contaminants arising from agriculture. NFU report

In this inter-agency project we will bring together expertise in climate change (Hadley Centre), animal disease (VLA, CEFAS), plant disease (CSL), chemical usage (CSL), chemical exposure modelling (CSL), microbial exposure modelling (VLA) and environmental economics (CSL), ecotoxicology (CEFAS) and marine risk assessment (CEFAS) to assess the impacts of climate change on the entry of pathogens and contaminants of agricultural origin from soils to ground waters and surface waters. These data will then be used to assess potential impacts on 1) agriculture – arising from the use of contaminated water in farming and the potential exposure through flooding; and 2) aquatic systems – arising from exposure to contaminants and pathogens.

The integration of skills across the agencies allows an holistic systems approach that takes account of interactions between the system components.

The overall aim of this study is to assess the potential impacts of climate change on the environmental risks of agricultural pathogens and contaminants. This will be achieved using the following specific objectives:

1. To generate appropriate data from climate system models for a range of climate change scenarios;
2. To evaluate the implications of climate change on a) plant and animal disease prevalence and pattern; b) chemical use; and c) transport of pathogens and contaminants to aquatic systems;
3. To investigate (using exposure modelling) the effects of climate change on the environmental transport and fate of pathogens and chemical contaminants;
4. To assess impacts of each of the scenarios on aquatic and/or agricultural systems;
5. To propose potential management options; and
6. To disseminate the results to key stakeholders.

It is beyond the scope of this study to consider all pathogen types and chemical contaminants so one pathogen and a selection of chemical contaminants from a range of classes will be used as ‘model’ contaminants to explore the implications of climate change.
Time-Scale and Cost
From: 2006

To: 2007

Cost: £142,284
Contractor / Funded Organisations
Central Science Laboratory
Climate and Weather              
Climate Change              
Environmental Protection              
Sustainable Production              
Water Pollution              
Water Quality              
Water Quality and Use