Pesticide poisoning of animals

Information Section--Fd Chem. Toxic. Vol. 32, No. 2 The Panel proposes new terms of reference for itself to incorporate the above principles. Its function should be to advise on the implications of novel foods and food processes for public health, taking account of their impact on the nutritional safety of the diet; on human metabolic pathways and physiological functions that may have beneficial or adverse effects on the long-term health of the population and potentially vulnerable subgroups; and on the nutritional value of the diet in relation to current dietary recommendations and national targets. The report also discusses some specific examples of nutritional issues arising from novel foods and processes that have been submitted for evaluation to the Advisory Committee on Novel Foods and Processes. In the case of fat substitutes the Panel acknowledges that they might make a valuable contribution to a lower fat diet, but feels unable to endorse their use as an effective way of achieving a lifelong reduction in risk of diseases related to dietary fat. Their effect on absorption of fat soluble vitamins and on the overall composition of the diet should also be considered. Soluble sugar beet fibre has been proposed for addition to granulated sugar, but its effect on micronu-

trient uptake and intestinal function requires eludication. The Panel also questions the appropriateness of using a vehicle such as sugar, the consumption of which COMA had advised should fall, to increase fibre consumption. Other submissions still being evaluated include interesterified fats (restructured triglycerides), with a fatty acid profile resembling that of human breast milk fat, for use in pre-term infant formulae; fructo-oligosaccharides as sugar substitutes; and caprenin (caprocaprylobehenin) for replacing cocoa butter and confectionery fats. The potential nutritional significance of genetic modification to the food supply is at present uncertain, but the Panel notes that transgenesis (the introduction of DNA from one species into the genome of another) may produce food of significantly altered composition or quality, that should be monitored from a nutritional perspective. [The Nutritional Assessment of Novel Foods and Processes. Report of the Panel on Novel Foods of the Committee on Medical Aspects of Food Policy. Department of Health Report on Health and Social Subjects 44. HMSO, London, 1993, pp. vii + 22. £4.50.1

THE ETHICS OF GENETIC The Committee on the Ethics of Genetic Modification and Food Use, established last year, has published its conclusions. The Committee sees no overriding ethical objections to the use of organisms containing copy genes of human origin as food, subject to the necessary safety assessment. However, A C N F P (Advisory Committee on Novel Foods and Processes) guidelines should be expanded to discourage the use of all ethically sensitive genes in food organisms where alternatives are available. Organisms from genetic modification programmes that can be clearly demonstrated not to have been modified should also be allowed into the food chain without restrictions, beyond those that apply to other types of animals from experimental programmes. Because some people may object on ethical grounds to the consumption of organisms containing copy genes of human origin, or from animals that are the subject of religious dietary restrictions, and certain vegetarians may dislike consuming plants containing copy genes of animal origin, the Committee considers that all such food products should be labelled to allow these groups to make an informed choice. A de minimis principle should apply in recognition of the practicalities of the situation, and derived products of specific, non-genetic nature need

MODIFICATION

not be labelled. As labelling may not provide all the information desired by consumers, industry and Government should explore the prospects for additional means of informing the public on the modifications applied to particular foods. The Committee observes that the dilution of the original host DNA during its introduction into another organism, or the use of complementary DNA (synthesized using messenger RNA as a template, which means that the original DNA is not involved in the cloning procedure) results in transgenes losing their original status, in the sense that they are manufactured in vitro rather than derived directly from a donor organism. A number of ethical objections surrounding the use of introduced genes might also be removed if the genes were entirely synthetic. It recommends that these issues should be further debated, particularly within the religious communities, to see if they might offer a way forward. [Report of the Committee on the Ethics of Genetic Modification and Food Use. M A F F . HMSO, London, 1993, pp. vi + 43. £7.95.] The Government proposes to accept these recommendations, subject only to review of labelling issues by the FAC (MAFF New Release 307/93, 20 September 1993).

PESTICIDE POISONING Pesticides were implicated in 174 of the 655 animal poisoning incidents investigated by the English, Welsh and Scottish Agriculture Departments during

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1992. Of the pesticide-related incidents, 146 involved vertebrates, 15 involved beneficial insects (honey- and bumble-bees) and 13 involved suspected baits and

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suspicious substances. Only six of the vertebrate incidents were definitely attributed to approved uses of pesticides. These included the deaths of three dogs poisoned by difenacoum on farms; another dog poisoned by metaldehyde slug pellets in a garden; bats from a roof space where the timbers had been treated in the past with 7-HCH and pentachlorophenol; and a cat that had been in contact with a dog treated externally with a veterinary formulation containing permethrin. Some of the 26 vertebrate incidents that were of uncertain origin may also have arisen from approved uses. Misuse of pesticides occurred in 17 vertebrate and suspected bait incidents, mainly involving rodenticides, molluseicides and seed treatments, and another II0 arose from deliberate abuse, a-Chioralose, strychnine, metaldehyde and paraquat were most commonly abused, as in previous years (Pesticide Poisoning of Animals 1991: Investigations of Suspected Incidents in Great Britain. A Report of the Environmental Panel of the Advisory Committee on Pesticides. PB 1054, 1992, pp. vii + 39. M A F F Publications, London, £2.95). Mevinphos accounted for only four incidents, as compared with 18 in 1991, a finding attributed to the lack of supplies prior to with.

ANIMAL

PROCEDURES

The Animal Procedures Committee has published its 1992 annual report. This notes that the fixed dose procedure has, as forecast, been included in OECD guidelines as an alternative to the LD~0 test (Pesticide Poisoning of Animals 1991: Investigations of Suspected Incidents in Great Britain. A Report of the Environmental Panel of the Advisory Committee on Pesticides. PB 1054, 1992, pp. vii + 39. M A F F Publications, London, £2.95; OECD Publications, 2 rue Andre Pascal, 75775 Paris, Cedex 16, France £17,00), but not as a preferred alternative. Data from LDs0 testing may therefore still be required by some regulatory authorities, and pressure to ensure the universal acceptance of alternatives is needed. The I% increase in experimental procedures on animals during 1991 (Statistics of Scientific Procedures on Living Animals, Great Britain, 1991. Home Office. Cm 2023. HMSO, London, 1992. pp. 49. £9.60) is regarded as disappointing. The main causes were an increased ability to modify genetic material, which has led to more work in many areas of biomedical science, and the implementation of new rules on re-use of animals. However, there has still been a reduction of more than 15"/, over the last 15 years, and cosmetics tests, rabbit eye irritation tests and primate experiments all declined during the year. Two project lieence applications involving exposure of rats to tobacco smoke were recommended for approval during 1992. The purpose of the first was to correlate changes in a range of tissues with those seen in blood, as only samples of the latter are

drawal of approval for its use (at the end of February 1993). Incidents involving beneficial insects fell by an encouraging 47% in 1992, and followed a 15% decrease in the previous year. Varroasis (a bee disease) may have contributed to the decrease, but the use of safer compounds such as pyrethroids for spraying fields, and a much greater awareness by farmers and contractors of the problems of spraying. may also have been responsible. Bendiocarb was involved in four of these incidents, dimethoate in three and triazophos in two. There were a few cases of malicious poisoning of honeybees (usually by neighbours), and preparations for the control of pigeon mites containing malathion were used in two such incidents. Altogether there were 10 successful prosecutions for illegal use or misuse of pesticides during the year, and a number of further cases are due to be heard in 1993. [Pesticide poisoning of animals 1992: investigations of suspected incidents in the United Kingdom. A report of the Environmental Panel of the Advisory Committee on Pesticides. By M. R. Fletcher & K. Hunter. PB 1434, 1993, pp. viii+44. £2.95 from M A F F Publications, London SE99 7TP.]

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REPORT

usually available from human studies. The findings will be used to develop in vitro methods for monitoring genetic damage caused in humans by environmental pollutants. The second involved the use of tobacco smoke as an experimental tool to study lung disease, and rats were to be used only when human tissue could not be obtained during life. In the second case the Committee stipulated that the rat model should be validated before the applicant proceeded to more advanced studies. One application to test cosmetics ingredients, in order to provide base set data required for the manufacture and transportation of new chemicals, was also approved during the year. The Committee was asked by the Home Office to consider whether there was a case for extending the controls of the Animals (Scientific Procedures) Act 1986 to cephalopods (octopus, squid, nautilus and cuttlefish). It concluded that current scientific evidence was insufficient to suggest with any certainty that cephalopods can experience pain and suffering, but that the benefit of the doubt should be given to Octopus rulgaris, about which most is known and which is of particular concern. Research grants were awarded during 1992 for projects to define the most important behavioural needs and housing preferences of laboratory rodents, in order to assess the need for improvements in caging; to develop a monoclonal antibody technique for in vitro assay of clostridial protective antigens: to validate an alternative in vivo assay in mice for botulinum toxin type A, using a non-lethal endpoint