Royal Commission on Environmental Pollution

The interests of the Food Standards Agency in relation to long term effects of chemicals in the environment may be summarised as follows:

- Levels of environmental chemicals (pollutants, contaminants, pesticides, natural chemicals, etc) in different food types.

- Transport processes of chemicals through the environment before entering the food chain, allowing us to predict the impact from routine emissions from industry or from a major accident.

- Bioavailability of chemicals from the environment to food animals and from the food matrix to humans.

- Risk assessment and risk management of chemicals in food.

- Research into potential human health effects of chemicals that occur unavoidably in the food matrix, taking into account possible beneficial or protective effects of other components of those foods.

- Communication of risk.

Broad topics to be covered:
a. Existing scientific knowledge on long term effects, and future research needs.
Existing scientific knowledge is limited by the difficulty of linking cause and effect in the presence of multiple exposures. With acute effects, it may be possible to make a direct connection between the exposure and a response, such as in the examples of gastric irritation resulting from contamination of canned foods with tin, or some food allergens. With occupational exposure, it can be possible to detect increased incidence of disease in workers that have been exposed to specific chemicals over prolonged periods. However, there is much greater uncertainty regarding the nature and levels of chemicals to which the general public may have been exposed, because of the inherent limitations in epidemiological studies. It is generally not possible to predict whether long term exposure via food may have contributed to health problems that arise in the general population.

The approach of the Food Standards Agency is to identify potential causes of concern, based on all available information, such as the physicochemical and toxicological properties of a chemical, as well as any information on human studies. If tolerable intakes have been established (by expert committees, either at the UK, EU or international level), then these are compared with estimated dietary exposures and action taken to reduce levels of such exposure, where this is desirable and feasible. For chemicals with certain types of effect, such as genotoxic chemicals, current scientific understanding does not support identification of a tolerable level of intake and therefore levels in food should be reduced to as low as is technically achievable. If epidemiological studies indicate that such chemicals may lead to human health effects (e.g. cancer), then the Agency may decide to commission further research in order to strengthen the weight of evidence and support risk management.

However, we consider that it is not feasible to take a generic approach to long term effects of chemicals. Each chemical, or group of related chemicals, need to be considered on a case-by-case basis, taking into account the individual properties and the quality of the specific database. In general tolerable intakes should be established at levels that avoid possible interactions between different classes of chemical. Where a number of chemicals are know to have similar toxicological properties, then it may be possible to consider them as a group, such as in the example of calculation of "TCDD equivalents" for the dioxins and dioxin-like PCBs. A new initiative of the Food Standards Agency is to establish a Working Group of the Committee on Toxicity to examine the potential for combined effects of mixtures (cocktails) of pesticides and veterinary medicines with similar biological action.

b. How chemicals are best assessed and potential hazards and risks identified. Approaches to identification of hazards and risks of chemicals have been defined by a number of organisations and expert committees, with specific requirements dependent on the type of chemical. In some areas of hazard identification, particularly mutagenicity testing, there are very active programmes aimed at continual development and improvement of the methodology, taking advantage of advances in scientific understanding and technology and considering the biological relevance of the results.

In other areas, there are major uncertainties with regards to the relevance and interpretation of the available methods. This particularly applies to the "endocrine disrupting substances", for which there are currently no validated methods of classification, and no general agreement on the potential human health effects associated with them. Several major initiatives, at EU, US and OECD levels, are currently focussing on establishment of valid methods for assessing endocrine disruption potential. A new research programme is due to be announced under the EU Framework Programme Five in June 2001. There is a common perception that the natural phytoestrogens have beneficial effects, and that the synthetic "xenoestrogens" are harmful. There is currently insufficient scientific information to allow conclusions to be drawn and the Food Standards Agency is funding research that aims to advance scientific knowledge in this important area. Furthermore, food contains a wide range of other toxic substances such as mycotoxins and process contaminants and that the presence of these compounds may represent a greater health risk than environmental contaminants.

A second issue of note relates to the detection and relevance of subtle neurological effects and effects on the immune system, such as allergy. These have been highlighted as areas of scientific uncertainty in expert committee discussions. Particular concerns include developmental effects in children, which may be mediated by exposure in utero and/or during infancy and early childhood, and for which there is little understanding of the role in longer-term health and behavioural problems.

Thirdly there is a need to incorporate new approaches into all areas of toxicological testing. This particularly relates to use of genomic and proteomic techniques, which may ultimately offer the potential for development of methods that are quicker to perform, more sensitive, use fewer experimental animals and produce results which are more directly relevant to humans than the conventional approaches currently in use.

For chemicals in food, risk assessment can be subdivided into effects for which it is considered possible to establish a level of exposure from the diet that is unlikely to result in harm, and those for which it is assumed that there may be some, albeit very small, risk associated with any level of exposure. For the former, the scope for improvement relates to reduction in the levels of uncertainty and use of "safety factors" that are based on scientific data rather than historical default values. Research on these issues is being funded within the Food Standards Agency and also by the Interdepartmental Group on Health Risks of Chemical (IGHRC). For those chemicals that cannot be ascribed an acceptable or tolerable level of intake, particularly genotoxic carcinogens, there is a need for development of methods for mathematical estimation of risk which incorporate specific mechanistic information rather than relying on generic models. The Agency is funding research on biomarkers of exposure and effect of genotoxic agents, the results of which could be incorporated into risk assessment models with direct relevance to human exposure via the diet.

c. Principles to be followed in regulating chemicals, while capitalising on their potential benefits. The Food Standards Agency is less able to contribute to this area. For additives and processing chemicals, it is expected that the manufacturer should demonstrate the need for the chemical, along with its safety. Contaminants that occur inadvertently in foods are generally pollutants without potential benefit and the main aim is to limit release of potentially harmful substances into the food chain. The Agency is a statutory consultee under the Environment Protection Act and Radiological Safety Act and provides comments direct to the Environment Agency on emissions.

Issues to be addressed:
The Royal Commission has identified 18 issues related to the broad topics. The Food Standards Agency would be willing to provide information from its own activities and also the opinions of its expert committees on the majority of these, should this be required for the study. In addition to many of the technical aspects, the Agency is particularly committed to the following issues (numbered as in the RCEP letter):

5. The adequacy of chemical and/or biological monitoring. The Agency has a long running programme of surveys on chemicals in food which are used to assess exposure of consumers to chemicals from food. The surveys are also a useful means of assessing changes in environmental levels of some chemicals. For example, our data shows that the levels of PCBs and dioxins in milk have fallen significantly over the last 10 years as a result of reduced environmental contamination.

12. Incorporation of people's values into the process - taking into account perceptions of risk and results of consultations in order to allow informed choice.

14. Openness and transparency of the assessment process. - The Agency would also be in favour of supporting effective co-ordination between national and international bodies in assessment and control of different types of chemical (issue 15). This is seen as an important aim that is not adequately addressed at the current time.

Conclusions
The Food Standards Agency endorses the broad aims of the Royal Commission study on long term effects of chemicals in the environment. We note that the study has a very broad focus, and that some aspects are currently subject to intensive international activity. We recommend that the RCEP study would offer greatest value by particularly focussing on other areas of concern, for which those of most relevance to the Food Standards Agency include:

- Comparative risk assessment for natural and synthetic endocrine disrupting substances.

- Detection and relevance of subtle neurological and developmental effects.

- Improvement of toxicity testing methods, particularly taking account of new technologies.

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