Abstract and Introduction
Abstract
Objective: Climate change is likely to affect the nature of pathogens and chemicals in the environment and their fate and transport. Future risks of pathogens and chemicals could therefore be very different from those of today. In this review, we assess the implications of climate change for changes in human exposures to pathogens and chemicals in agricultural systems in the United Kingdom and discuss the subsequent effects on health impacts.
Data Sources: In this review, we used expert input and considered literature on climate change; health effects resulting from exposure to pathogens and chemicals arising from agriculture; inputs of chemicals and pathogens to agricultural systems; and human exposure pathways for pathogens and chemicals in agricultural systems.
Data Synthesis: We established the current evidence base for health effects of chemicals and pathogens in the agricultural environment; determined the potential implications of climate change on chemical and pathogen inputs in agricultural systems; and explored the effects of climate change on environmental transport and fate of different contaminant types. We combined these data to assess the implications of climate change in terms of indirect human exposure to pathogens and chemicals in agricultural systems. We then developed recommendations on future research and policy changes to manage any adverse increases in risks.
Conclusions: Overall, climate change is likely to increase human exposures to agricultural contaminants. The magnitude of the increases will be highly dependent on the contaminant type. Risks from many pathogens and particulate and particle-associated contaminants could increase significantly. These increases in exposure can, however, be managed for the most part through targeted research and policy changes.
Introduction
Weather and climate factors are known to affect the transmission of water- and vector-borne infectious diseases as well as the transport of chemicals around the environment. Climate change may therefore have important impacts on the dispersion of pathogens and chemicals in the environment. In addition, changes in climate are likely to affect the types of pathogens occurring as well as the amounts and types of chemical used for a range of scenarios. Future risks of pathogens and chemicals could therefore be very different than today, so it is important that we begin to assess the implications of climate change for changes in human exposures to pathogens and chemicals and the subsequent health impacts in the near term and in the future. Therefore, in this review, we discuss how health risks might change by exploring the current scientific evidence for health effects resulting from environmental exposure to pathogens and chemicals arising from agriculture; the potential impacts of climate change on the inputs of chemicals and pathogens to agricultural systems; and the potential impacts of climate change on human exposure pathways to pathogens and chemicals in agricultural systems. Finally, we provide recommendations on approaches to mitigate any adverse increases in health risks.
In this review we focus on the U.K. agricultural environment, but some of the conclusions are applicable and relevant to other countries in temperate areas as well as sectors other than agriculture. We focus on environmental routes of exposure, and do not consider occupational exposure pathways or direct application of chemicals to food animals.