Royal Commission on Environmental Pollution

You wrote to me on 19 October about the Royal Commission's new study on long term effects of chemicals in the environment. Lindsay Mitchell has been co-ordinating our input to this work and, I know, met you on 15 January (he has been absent from the office since then).

I attach a note setting out some thoughts on what we would regard as some key issues for the study though this is not an exhaustive list. The note takes account of your meeting with Lindsay last month. It does not therefore cover for example the precautionary principle though you may wish to invite Dr Robin Foster - the contact point for the Inter -departmental Liaison Group - to comment on this. His address is Health and Safety Executive, Rose Court, Southwark. Nor does it include a description of the arrangements for licensing pesticides and veterinary medicines on which I understand you would prefer to take oral evidence. It also covers some examples of MAFF research in this area, including the toxic elements of sea lice treatments in fish farms, which you specifically asked about.

I understand you also expressed an interest in the terms of the interim response to the Phillips Inquiry report. As you will be aware, it was published on 9 February, and a copy is available from the MAFF website on www.maff.gov.uk.

COMMENTS FROM MAFF

The broad remit of the Department across both terrestrial and marine environments leads to difficulty in providing a succinct list of key problems for RCEP study. There are a number of generic issues that are pertinent to all aspects of the activity of the Department and these are outlined below with some examples of specific problems and MAFF initiatives to address them:

Pathways and Species of Concern (RCEP. 1)
It is clear that when dealing with very low concentrations of environmental contaminants it is interference with the reproductive and developmental processes have the greatest potential to do long-term damage. The effect of reproductive endocrine disrupters recently described for marine systems by CEFAS is a case in point, but is only one example of sub-lethal effect. There will be others to which we should be more alert, for example as a consequence of the increasing number of synthetic organic compounds that are being developed with specific biological activity. Even with reproduction-specific endocrine disrupters, we are still only skimming the surface of the huge range of possible effects. We are severely limited by our fundamentally weak understanding of the endocrine system (especially in invertebrates), and also by our limited knowledge of the way in which development is controlled at the molecular level. Another area of concern is the immune system which is even more poorly studied, but which is undoubtedly affected by chemical exposures.

Testing systems (RCEP. 2)
The present systems for determining environmental hazards of pesticides, veterinary medicines, biocides, offshore chemicals and general chemicals are predicated on the assumption that low acute toxicity equals low chronic toxicity, and that a few surrogate species are sufficient to represent the whole ecosystem, but this is clearly not universally the case. TBT is a good example of a substance that even now could still slip through regulatory testing systems. Even though early concern is expressed for substances that have a half-life longer than a few days, there is still a range of chemicals that can trigger long-term chronic effects as a result of transient exposure. Designing ever more elaborate testing systems is only a partial solution at best; viz. the development of 4 new fish tests for oestrogens/androgens (under consideration by OECD) and countless others for other animal groups will lead to proliferation of testing requirements which has severe ethical and economic problems and will still not be foolproof.

The Development and Use of Predictive Methods (RCEP. 4)
The more that is learnt about the environment the more mankind realises how complex are the ways that pollutants impact on the environment and how the environment responds. It seems as if no two geographic sites are the same, though many have common attributes. Similarly man and other animals respond to environmental pollutants in different ways depending on genetics, the environment, dietary factors and previous history. For example the action of sunlight on polycyclic aromatic hydrocarbons (PAHs) can lead to substantial increases in toxicity of these compounds. The complexity of natural systems and their inherent variability in response to pollutants means that the resolution and understanding of effects by experiment is becoming too time consuming and costly. There is a need for as better understanding of the basic mechanisms so that effects can reasonably be predicted and, equally importantly, the derivation of mathematical models capable of producing results (within acceptable margins of error) quickly.

The development of such models is no easy task however. Many current assessment systems extrapolate from high to low doses of pollutants without taking non-linear response mechanisms into account. Chemicals such as endocrine disrupters and other receptor-mediated contaminant effects depart from the classical threshold model and require full response curves to be developed. Furthermore the effects of mixtures of chemicals are largely unexplored.

Monitoring (RCEP. 5)
Even when predictive systems are much more robust and reliable problem compounds will still slip through the regulatory net and ultimately risk assessments can only be validated by monitoring. Our present programmes for marine environmental monitoring e.g. the national marine monitoring programme (NMMP) and FEPA validation monitoring programmes are integrated studies undertaken by a number of UK agencies (coordinated by MPMMG). Such programmes have a good track record in describing the spatial distribution and in some cases trends of effects by toxic compounds to determine the efficacy of control measures. Historically the basis of monitoring has been substance-specific but we are now moving towards biological testing and an "ecosystem approach" to assessment. In order to place our contribution to management of marine systems in a wider context, the ecosystem approach places more emphasis on biological response to the whole gamut of stressors including natural and man-induced physical disturbance, anthropogenic contaminants and naturally occurring toxins. The gap here is developing good sentinels and biomarkers for the impact of multiple stressors and making sufficient numbers of measurements in a cost-effective way. The development of genomics using multi-gene arrays combined with unattended devices for continuous monitoring is a potential way ahead.

Dealing with Uncertainty and for Lack of Data (RCEP. 7)
At the time when applications to release chemicals into the environment are under consideration, there are likely to be some uncertainties about their fate and behaviour, particularly in relation to long term effects. The use of predictive models can help and monitoring and reporting systems to be used post authorisation can provide additional confidence about the approach taken at assessment. It is also desirable to adopt a precautionary approach where there are data gaps. In cases were there is deliberate release into the environment (for example, products for the treatment of farmed fish) it is desirable that the assessment process is co-ordinated with that of the authorities responsible for granting site-specific discharge consents.

Regulatory Gaps (RCEP. 16)
The MAFF role of sustaining and enhancing the marine environment, including regulation of many marine activities, places the Ministry "downstream" of the regulatory assessments of other Departments and Agencies. A good example is in the sequence of approval of antifouling biocides by the HSE, discharge of spent material from dockyards by the EA, control of dredging activity by the EA and licensing of the disposal of harbour sediments to sea by MAFF RMED with scientific advice from CEFAS. Whilst the risk assessment for approval and discharge of active biocides is largely considered on the basis of single compounds, by the time the materials are entrained in marine sediments they are present as part of a complex mixture of trace contaminants from industrial-chemical and biocidal inputs. Accordingly risk assessment for disposal of this material to sea is more problematic. MAFF has recognised weaknesses and overlaps in regulatory systems and places emphasis on liaison with other Government Departments. One initiative here is to develop a Joint consenting Unit with DETR to ensure better communication on regulatory activity for dredging and disposal.

Current research
Responsibility for researching and monitoring pollutant impacts on the terrestrial environment and on human health rests largely outside of MAFF. And many of the chemicals released from agriculture (e.g. nutrients) have short-term rather than long-term impacts. However, MAFF R&D includes work on the impacts of pesticides, veterinary medicines and heavy metals on the environment.

The MAFF marine environment research portfolio is integrated with DETR programmes and largely delivered by CEFAS. Commissioned work is designed to provide constant improvement in our ability to manage marine systems and includes research on the molecular basis of contaminant effects, contaminant mixtures, UV-photoactivation, other modifiers of contaminant fate, endocrine disruption (notably here the EDMAR programme), improved methods of risk assessment, determining causality and monitoring of hazardous substances. A programme on the development of unattended monitoring systems for hydrographic parameters and nutrients is well advanced and is being linked electronically to the CEFAS website to provide real-time delivery of monitoring information.

EXAMPLES OF RESEARCH

Toxic Effects of New Sea Lice Treatments
The toxic effects of all new sea lice treatments have been examined during the product licensing and discharge consenting processes but these studies have been limited to a few sentinel species and there is currently little information on the wider ecological consequences of the use of these products. This project seeks to address the widely perceived research need in this area by conducting long term, broad scale BACI (Before After Control Impact) studies at a range of low energy fish farm sites and encompassing all the currently available or presently proposed sea lice treatment chemicals. The results of this research will answer commonly asked questions on the ecological significance of these chemicals under realistic treatment regimes with respect to macrofauna, zooplankton, meiofauna, benthic diatoms, phytoplankton and macroalgae. This proposal has been developed and costed on a 3 year basis but it is assumed that the study will require 5 years to deliver the results at a sufficiently high level of statistical certainty. The experimental design of the final 2 years of the 5 will be informed by the initial results and it may be possible within the first 3 years to discontinue study of those taxonomic groups which can be proven to show no response to particular treatment agents. It is therefore not possible to cost and plan the final 2 years at this stage but the assumption is made that a similar degree of more focussed effect will be required and at a relatively similar per annum cost. Decisions of the final 2 years activities will have to be made during year 2 of the project so that plans for years 3 and 4 can be put in place.

Toxins
A number of algal toxins occur in UK waters. Paralytic Shellfish Poison (PSP) is associated with algae of the genera Alexandrium, Gymnodinium and Pyrodinium. The illness comprises numbness in the mouth and fingertips followed by impaired muscle co-ordination. Respiratory distress and paralysis can occur and this may be fatal. The major toxin is saxitoxin but there are a large number of other toxic derivatives of the saxitoxin molecule, e.g. neosaxitoxin and gonyautoxin, which may be involved. (Diarrhoeic shellfish poison) DSP toxins are produced by algae of the genera Dinophysis and Prorocentrum. Predominant symptoms are diarrhoea, nausea, vomiting and abdominal pain. The major toxins are okadaic acid and dinophysis toxins 1, 2 and 3, although various others are known. Amnesic Shellfish poison (ASP) is caused by domoic acid produced by marine diatoms of the genus Pseudonitzschia. Symptoms include vomiting, diarrhoea, abdominal cramps and loss of short- term memory which may be permanent, in a small number of cases ASP has been fatal. Low levels of domoic acid have been detected at a number of sites in the UK but in most cases levels have been well below the maximum permitted level for foodstuffs set for this biotoxin.

There are several other algal toxins which may occur in British waters and which could have human health implications. Research undertaken by CEFAS recently found Azaspiracid (AZP), a toxin which causes DSP like symptoms, at the Camel Estuary in England. AZP is a major problem in the Republic of Ireland and has caused several outbreaks of human poisoning. Other potential problem biotoxins are gymnodimine, spirolides, pectenotoxin and yessotoxin. The power of mass spectrometrometry in biotoxin analysis has been demonstrated by CEFAS in terms of identifying new poisons in shellfish from England and Wales. Recently, an isomeric analogue of the DSP toxin Okadaic acid (DTX-2) has been confirmed to have impacted on shellfish from the northeast of England. From the same area and in addition to selected harvesting areas from the south and southwest coasts, a new toxin, azaspiracid has also been identified in a range of shellfish species. Collaborative publications, with the Cork Institute, detailing these findings are currently in press. The developed LC-MS technique has also enabled CEFAS to identify the causative toxins responsible for several incidences of human intoxication in England.

Endocrine Disruption in Marine Systems
The EDMAR Programme began in June 1998 and continues until the end of 2001. It is investigating whether there is evidence of changes associated with endocrine disruption in marine life and, if so, the possible causes and potential impacts. It follows on from work which demonstrated that flounder in some UK estuaries had changes consistent with endocrine disruption.

Funding for EDMAR is provided by the Department of the Environment Transport and the Regions (DETR), the Ministry of Agriculture, Fisheries and Food (MAFF), the Environment Agency (EA), the Scotland and Northern Ireland Forum for Environmental Research (SNIFFER) and the European Chemical Industry (CEFIC).

Five major UK laboratories are conducting the research: the CEFAS Burnham, Lowestoft and Weymouth laboratories, the Plymouth Environmental Research Centre (PERC), the Centre for Marine and Coastal Studies in Liverpool (CMACS), the FRS Marine Laboratory, Aberdeen (with assistance from the Scottish Environment Protection Agency) and the Astra-Zeneca Environmental Laboratory, Brixham.

Achievements to date include the development of methods to detect androgenic (masculinising) exposure in sticklebacks, assays to measure crab and shrimp vitellin (egg protein), histochemical assays for oestrogen receptor sites and vitellogenin (egg protein) in flounder and molecular probes for determination of vitellogenin in fish (sand goby and viviparous blenny).

Male flounder from some industrialised estuaries still show strong vitellogenin induction. Caught sand gobies exhibited no vitellogenin induction or intersex, but feminisation of secondary sexual characteristics is observed in male gobies in some estuaries. Viviparous blennies in some estuaries show induction of vitellogenin, and incidence of intersex.

Toxicity Identification and Evaluation (TIE) procedures deployed on the Tyne and Tees estuaries has identified 3 natural (steroidal) and 2 industrial (surfactant and phthalate) oestrogenic compounds as possible causes of the observed effects.

PAHs
Polycyclic Aromatic Hydrocarbons (PAHs) are common environmental pollutants which tend to concentrate in sediments close to industrialised and urban locations. They can also be found in lower, though still potentially significant, concentrations at more remote locations. They enter the sea from a range of sources including roads and traffic, coal and wood burning, and some industrial processes. Certain PAHs can be acutely toxic to aquatic life in highly contaminated locations and others may also have carcinogenic and other long-term effects under less contaminated conditions.

Since 1998, MAFF has been funding a study at the Centre for Environment, Fisheries and Aquaculture Science (CEFAS) to investigate the potential for ultra-violet light to increase the toxicity of PAHs in the surface levels of the sea. This has involved laboratory-based exposure experiments on fish eggs and larvae, and on invertebrate species.

The results support the broad thrust of previous findings by revealing increases in toxicity of, on average, 100x - 10x in the presence of environmentally realistic levels of UV light. Marine animals most likely to be affected are those, such as some flatfish, whose embryo or larval stages inhabit the surface levels of the sea where UV intensity is at a maximum. However, the study concludes that this effect is unlikely to pose a risk to commercial fish species at offshore locations.

Brominated flame retardants
Brominated flame retardants (BFR's) are technical flame retardants used in substances such as plastics, textiles, electronic, and packaging materials. Brominated flame retardants fall into two broad classes additive, were the active compound is not chemically bound to the material to be flame retarded and reactive retardants where the additive is chemically bound to the matrix. The former group include polybrominated diphenyl ethers (PBDE's), hexabromocyclododecane (HBCD) and the later tetrabromobisphenol A (TBBA).

PBDE's have, until recently been manufactured in the UK and are still used, although recent EU draft legislation will restrict production of the so called "penta mixes". The other common commercial mixes, the so called "octa mixes" and the deca BDE (which is 96% pure) will not be restricted. HBCD is manufactured in the UK and is an important commercial product. The additive BFR's have similar properties to many classic organochlorine compounds, they are persistent, bioaccumulative and toxic.

Work undertaken by CEFAS indicates that they are common aquatic environmental contaminants found in sediments and all trophic levels of the marine food web. They have also been found in pisciverous birds. In areas of former production and of continuing use concentrations of PBDE's are often found at similar or indeed higher concentration than PCB's. Trend data (on archive human milk samples) from Sweden indicates that unlike many persistent organohalogens were levels are in decline PBDE's level continue to increase and are of significant concern.

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