4^th IUTOX Congress of Toxicology in Developing Countries (4^th CTOX-DC), 6–10 November 1999, Antalya, Turkey

Reports from IUPAC-Sponsored Symposia

4^th IUTOX Congress of Toxicology in Developing Countries (4^th CTOX-DC), 6–10 November 1999, Antalya, Turkey

6-10 November 1999,

Antalya, Turkey

This meeting, sponsored by the Turkish Society of Toxicology along with IUPAC and the International Union of Toxicology (IUTOX), covered a wide variety of topics at a high level and was attended by many of the worldís leading toxicologists. It started with a workshop on environmental oestrogens that provided an overview of the problem and stimulated active discussion. The conclusion of the workshop was that the evidence for significant harmful effects of oestrogenic substances in the natural environment is still limited to a few examples and that no definite conclusions can yet be reached about any effect on the human species. Current research in this area will, we hope, clarify matters and alleviate public concern.

The workshop was followed by a series of symposia. Topics included safety issues in developing countries, life styles and health, pesticides, neurotoxicity of drugs of abuse, advances in understanding allergic sensitization, occupational exposure to chemicals in the workplace, risk assessment and chemical management, advances in molecular toxicology, and ecotoxicology. There were plenary lecture sessions on genetic polymorphism, xenobiotic toxicity, and clinical toxicology. In addition, there were two more workshops on chemical risk assessment in theory and practice and educational needs for developing countries, as well as oral and poster presentations.

So many issues were raised and discussed that one can pick out only a few of special note. A recurring theme was the lack of facilities for local experts to monitor chemical exposures in developing countries. This situation makes it very difficult to enforce legislation for chemical safety, and it may be a particular problem with pesticides made by local manufacturers in developing countries. These pesticides are bought by farmers because they are cheap, but they may contain harmful impurities that are no longer permitted in the developed countries.

Underlying many of the presentations was concern about risk assessment. Toxicology defines the intrinsic hazard associated with a chemical and relates this hazard to exposure in the form of dose-response and concentration-response curves. However, it tells us nothing about risk, which is a function of the way in which a chemical is used and the probability of a person or other organism being exposed to a sufficient amount of a chemical to cause harm. Thus, a certain chemical may be classified as toxic, but this does not mean that it will necessarily cause harm. If little or no exposure to this chemical occurs, or is likely to occur, risk of harm may be negligible. Determining exposure is a challenge for chemists and may require development of new techniques. For example, guidelines for exposure to elements other than carbon are largely set in relation to total elemental concentration. Chemical speciation is ignored at least partly because analytical chemists often do not speciate elemental analysis. For example, arsenic analysis is rarely quoted as arsenite, arsenate, or organic species, although we know that their toxicology is different. Risk assessment based on total arsenic analysis is meaningless.

Other unifying concerns were related to differential susceptibility to the effects of chemicals owing to genetic and environmental differences and the problem of assessing mixed exposures. The effects of diet were given due attention. Ecotoxicology got less attention than it deserves, and the organizers of the next congress of this kind may wish to include more on this area.

The workshop on educational needs for developing countries was particularly interesting. It is clear that at least some developing countries are not short of expertise but, rather, lack the facilities to make full use of the experts available. It also appears that there is a lack of expertise in certain specialist areas and that the international organizations should identify these areas in order to help provide necessary course material. However, there seems to be a lack of coordination between international bodies in providing such material and in maintaining an ongoing educational program. Perhaps IUPAC and IUTOX could get together with the International Union of Pharmacology (IUPHAR) and initiate a body for coordinating toxicological education at the international level. Such a body could ensure that educational material of recognized quality was available, preferably through the Internet, and could respond to requests for specific courses to be organized.

Nearly 300 people participated in the 4th CTOX-DC, and it succeeded well in reflecting both our current understanding of important areas of toxicology and the significance of toxicology for safe use of chemicals in both developed and developing countries.

Dr. John H. Duffus

Chairman, IUPAC Commission on Toxicology (VII.C.2)

The Edinburgh Centre for Toxicology

Edinburgh EH9 2JD, Scotland, United Kingdom