Environmental Change and Rising DOC Trends: Implications for Public Health

Lead Research Organisation: Bangor University
Department Name: Sch of Biological Sciences

Abstract

This highly integrated multidisciplinary project engages the skills of environmental scientists, mathematical modellers, analytical chemists, toxicologists and public health scientists to address health vulnerability issues resulting from future environmental change impacts on soil-water ecosystems at a regional scale. It will address the health implications of a recently observed alarming trend for rising Dissolved Organic Carbon (DOC) concentrations in aquatic ecosystems used for potable water abstraction. Over the past two decades the concentration of dissolved organic carbon (DOC) in many source waters of these source waters has more than doubled and continues to rise (Freeman et al., 2001). There is increasing evidence to suggest that the process is being driven by environmental changes such as a decline in acid deposition (Evans et al., 2006; Monteith et al. 2007), combined with rising temperatures, increased frequency of drought and changes in the seasonal distribution of rainfall. We aim to analyse data from monitoring programmes and various other studies to allow us to predict the likely impact of future changes in climate and air pollution on DOC concentrations in water entering reservoirs and water treatment works. The increase in the level of DOC reaching water treatment works has major implications for human health. Organic matter in raw water is only partially removed by conventional treatment using inorganic coagulants; what remains may react with disinfectants. During chlorination of water supplies the chlorine reacts not only with the microorganisms but also with most of the other organic material present in the water, either dissolved or in suspension. This produces a range of organic compounds known as disinfection by-products (DPBs) including a group of chemicals called trihalomethanes (THMs), plus haloacetic acids, halonitriles, haloaldehydes and chlorophenols. We will carry out laboratory experiments to test the likely implications of the future changes in DOC we have predicted for the generation of these compounds within the water treatment system. Furthermore, a wide variety of other chemical contaminants, derived from air pollutants from industry, fertilizer application and urban waste water may bind (by sorption) to natural organic matter and be transported into reservoirs and water treatment works in association with DOC. Their fate within the treatment system, i.e. whether they are removed or remain within solution, depends heavily on the type of contaminant, the nature (or quality) of the DOC, the chemistry (e.g. pH and ionic strength) of the aqueous solution and the type of treatment process. We will carry out laboratory experiments to determine the extent to which these contaminants are bound to DOC at the point they enter the water treatment process and what is likely to happen as a result of the process, e.g. the extent to which contaminants are likely to be removed or remain in solution. Living organisms respond in various ways and on a spectrum of timescales when exposed to chemical contaminants. Some effects in organisms are immediate while others effects may be delayed and not show up for 10 or 20 years or more; for example, cancer in humans. We will draw on existing risk assessment approaches from national and international (EU) governmental agencies to evaluate the potential human health impacts of changes in levels of a range of contaminants under environmental change scenarios. Finally, we will bring together the findings of our research in the form of a Decision Support System (DSS) that will provide information to the water industry, the environmental agencies and other stake holders. The DSS will provide predictions of likely DOC trends under future climate change scenarios and the likely importance of predicted changes for wider water quality and human health.

Publications

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Delpla I (2014) A decision support system for drinking water production integrating health risks assessment. in International journal of environmental research and public health

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Fenner N (2011) Drought-induced carbon loss in peatlands in Nature Geoscience

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Gough R (2016) Relationships between reservoir water quality and catchment habitat type in International Journal of Environmental Technology and Management

 
Description The findings of the project can be amalgamated and incorporated into a Decision Support System (DSS) which can assist in the management of water catchment environments and water treatment procedures.
Exploitation Route The findings of the project can be amalgamated and incorporated into a Decision Support System (DSS) which can assist in the mamanagement of water catchment environments and water treatment procedures.
Sectors Environment

 
Description This has directly led to new jobs through the creation of specialised catchment management teams and new water treatment measures by the water industry, including water companies Welsh Water and United Utilities - improving drinking water quality for at least 5 million households in England and Wales. According to Welsh Water's Operations Director: "through implementation of management adjustments to rising trends in DOC, every UK customer receiving water from upland catchments, has benefitted from improved water quality through this research". The research findings have been the justification for millions of pounds of funding secured by the water companies, and central to further investments driven by their increasing recognition of ecosystem services and the importance of peat carbon storage .
First Year Of Impact 2008
Sector Agriculture, Food and Drink,Environment
Impact Types Economic,Policy & public services

 
Description NERC Large Grants Scheme
Amount £445,000 (GBP)
Funding ID NE/K010689/1 
Organisation Natural Environment Research Council 
Sector Public
Country United Kingdom
Start 10/2014 
End 10/2017
 
Description Welsh Water Funding
Amount £66,431 (GBP)
Funding ID F003597 
Organisation Welsh Water 
Sector Private
Country United Kingdom
Start 05/2012 
End 10/2013
 
Description Welsh Water Funding
Amount £66,431 (GBP)
Funding ID F003597 
Organisation Welsh Water 
Sector Private
Country United Kingdom
Start 10/2012 
End 09/2015
 
Description PhD Studentship - Impact of Climate Change on Surface Water Quality and Drinking Water Quality and Treatment 
Organisation Imperial College London
Country United Kingdom 
Sector Academic/University 
PI Contribution The PhD project, which is funded by the Grantham Institute for Climate Change, will examine the possible impact of climate change on the nature and treatability of dissolved organic carbon (DOC) released from different soil and plant materials. This will involve an extensive laboratory programme of controlled ?climate change? simulation experiments and subsequent laboratory analysis of DOC quality and quantity, and treatability aspects. Changes in the nature of DOC and formation of disinfection by-products will employ state-of-the-art analytical techniques (e.g. LC-SEC/GC-MS, fluorescence spectroscopy), and will build on two recent EPSRC studies on the occurrence and formation of disinfection by-products (haloacetic acids and NDMA). Aspects of the proposed project complement an existing NERC project on ?DOC, Climate Change and Health? led by Chris Freeman (Bangor) in collaboration with Welsh Water. This project will bring together expertise in water quality and treatment from Imperial College London (Graham, Templeton, Bond) and environmental processes from Reading (Clark) and Bangor (Freeman). In addition to establishing the scientific basis of DOC behaviour under simulated effects of climate change, the project will seek to apply these findings through the development of decision support methodologies for managing changing source water quality at water treatment plants, in collaboration with selected UK water company partners.
Start Year 2012