Royal Commission on Environmental Pollution

Introduction

1.    The Natural Environment Research Council (NERC) welcomes this opportunity to provide evidence into the Royal Commission for Environmental Pollution's (RCEP) scoping study: Chemicals in the Environment.

2.    NERC is the UK's leading organisation for basic, strategic and applied research and training across the spectrum of the environmental sciences. NERC's purpose is to support high quality scientific research, survey, monitoring and postgraduate training with the objective of enhancing knowledge, understanding and prediction of the environment and its resources. NERC achieves this through its support of scientists at universities and through its own Research Centres: the British Antarctic Survey (BAS); the British Geological Survey (BGS); the Centre for Ecology and Hydrology (CEH); the Southampton Oceanography Centre (SOC - a joint venture with the University of Southampton); Dunstaffnage Marine Laboratory (DML); Plymouth Marine Laboratory (PML) and Proudman Oceanographic Laboratory (POL). This memorandum includes inputs from PML, BGS, CEH and the School of Environmental Science UEA.

3.    NERC has funded a number of thematic programmes that are relevant to this study, including Environmental Diagnostics which includes work on environmental clean-up, remediation, and waste management, and the Urban Regeneration and Environment Programme (URGENT) dedicated to research within urban areas of the UK on contaminated land and water quality.

a.     An overview of existing scientific knowledge on the long-term effects of chemicals in the environment, and further research needs.

4.    We note that the Commission's study will provide an input to the new Chemicals Stakeholder Forum. However, it is not clear how the Forum will interact with the new Advisory Committee on Hazardous Substances (ACHS), which is currently being established by DETR, and the Interdepartmental Group on Health Risks from Chemicals (IGHRC), chaired by David Shannon of MAFF. Excellent communication between all relevant groups is important to ensure a co-ordinated approach and prevent duplication.

5.    To establish the quantity and distribution of chemicals which have accumulated as a result of human activity, it is first necessary to ascertain their natural level of occurrence. Assessment of the overall significance of such chemicals requires knowledge of the factors which control their mobility. This helps to establish whether a pathway exists from the contaminant source to humans and natural ecosystems. The Commission should therefore lend its support to long-term, strategic research programmes which underpin many of the issues raised in this study.

6.    There are many other naturally occurring chemicals already in the environment derived from the dissolution of soils and rocks, including arsenic, copper, lead, radon and hydrocarbons which are known to impact health. Concentrations of these substances will vary spatially and with time. How these chemicals interact with man-derived chemicals to impact on health is not well understood and would benefit from further research.

7.    Another unknown is the distribution of the legacy of chemical pollutants in the environment that has resulted from man's activities. Some are stored and isolated from the surface by physical and chemical conditions. Changes in these conditions may release such chemicals, or their degradation products, back into the environment. Many of these degradation products may be more water-soluble (e.g. oxidation products of methylbenzene) and therefore potentially mobile. This obviously has implications for groundwater quality, since groundwater is recharged by both surface water and rainfall. Water can take decades to travel from the area of recharge to the point of abstraction to supply drinking water. Chemicals entering the system as pollutants thus have the potential to reappear many years later.

8.    Whilst non-priority pollutants are being addressed, the question of contaminant mixtures and their effects is not adequately identified. Despite much discussion our actual knowledge of the synergistic effects of exposure to various groups of chemicals remains poor. Studies of human health in areas of naturally elevated trace element abundance, and in areas of degraded land quality, highlight significant gaps in our understanding of not only bioavailability but of human exposure. These subject areas need further research to improve linkages between hazard derived guidelines, the precautionary principal, natural and enhanced anthropogenically derived exposure, actual health outcomes and sustainability. This is particularly important if risk assessment continues to underpin policy. The effect of exposure to various isomers (selective production of both chemical and chiral isomers is increasingly being undertaken to maximise activity) and environmentally relevant degradation products needs to be encouraged. In addition, whilst endocrine disrupters and selected Persistent Organic Pollutants (POPs) are specifically identified, possibly genotoxins/carcinogens should also be specified.

9.    Whilst radioactive substances have been excluded from the remit of this report it is worth noting that significant differences exist between the principals used in assessing the long term effect of radioactivity and the long term effects of chemicals on the environment. Also some chemicals, such as uranium, have a toxicity that can be attributed to both their chemical and radiological behaviour. It may well be the case that experience gained and data from the study of radiological exposure is of direct benefit to the study of the long-term effects of non-radioactive compounds. A recent briefing, prepared by BGS on Depleted Uranium is attached for information.

10.    It is recognised that chemicals in the environment occur as cocktails both natural and man-derived and the source, term and pathways for impacting on health are complex. The BGS is currently working on an artificial stomach to improve the models to help us understand better the way in which ingested material enters the human body.

b.     How chemicals are best assessed and potential hazards and risks identified.

11.    The release of many new compounds each year takes place with very little known about the possible effects. Science is not very good at predicting all forms of environmental damage from first principles so we use toxicity testing using procedures we have established to deal with existing problems. That is satisfactory so long as the new potential contaminant operates in the same way as existing contaminants. However, there is a risk of encountering totally new problems that may not be recognised by existing procedures because they have too short testing times or consider the wrong species or environment. This has occurred in the past with Tributyltin (TBT) and endocrine disrupters. This seems to be an argument for continuing long term and diverse studies of ecosystems aimed at fundamentally understanding them but recognising a by-product is that it will provide a potential warning system for problems. Existing monitoring systems may be inadequate for such purposes.

12.     There are a range of chemicals released into the environment deliberately which are not particularly toxic but which have long term effects - for example nitrates and other fertilisers. This emphasises the need for toxicity testing to consider the whole environment not a group of species in tanks in the laboratory.

13.    Related to that is the difference between chemicals that are deliberately released because there is a balance of benefit over risk, these include fertiliser and pesticide products, and by-products and accidental releases that in theory, we could try and regulate to zero emission. The latter are things that can in theory be fixed technologically; the former needs a better assessment of risk in the fullest environmental context. The discussion point six about quantities produced might consider quantities released in this context.

c.    The principles that should be followed in regulating chemicals, while capitalising on their potential benefits; that is, how identified problems are best addressed, and chemical manufacture, marketing, use, and disposal most efficiently controlled to protect human health and the natural environment.

14.    The inclusion of chemical and biological monitoring into a single point should aid integrated discussions. Links between professionals dealing with long-term effects of chemicals in the environment such as toxicologists, medical researchers, general practitioners, epidemiologists, earth scientists, environmental scientists and those within the chemical industry need to be much more positively encouraged to stimulate true interdisciplinary research. The Commission should review ways by which this might best be achieved such as by comparison with approaches used in other countries.

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