Exposure to multiple environmental agents and their effect

• Published in: Acta Paediatrica 2006-10, Vol.95 (s453), p.106-113
• Main Authors: KOPPE, JANNA G., BARTONOVA, ALENA, BOLTE, GABRIELE, BISTRUP, MARIE LOUISE, BUSBY, CHRIS, BUTTER, MAUREEN, DORFMAN, PAUL, FUCIC, ALEKSANDRA, GEE, DAVID, VAN DEN HAZEL, PETER, HOWARD, VYVYAN, KOHLHUBER, MARTINA, LEIJS, MARIKE, LUNDQVIST, CHRISTOFER, MOSHAMMER, HANNS, NAGINIENE, RIMA, NICOLOPOULOU-STAMATI, POLYXENI, RONCHETTI, ROBERTO, SALINES, GEORGES, SCHOETERS, GREET, TUSSCHER, GAVIN TEN, WALLIS, MAX K., ZUURBIER, MONIEK
• Format: Article
• Language: English
• Subjects: children's health; environment; environmental chemicals; Multiple exposure; precautionary principle; unborn baby
• ISSN: 0803-5253; 1651-2227
• DOI: 10.1080/08035320600886646

Introduction: All children are exposed to multiple physical, chemical and biological challanges that can result in adverse health effects before and after birth. In this context, the danger of multiple exposures cannot be assessed from a single‐chemical approach as used in classical toxicology. Aim: To open up a ‘negotiation space’ for the problem of multiple exposure to environmental stressors, defined as any physical, chemical or biological entity that can induce an adverse response. In this context, two further questions obtain: to what extent can synergistic risks be assessed, and how far could potential adverse effects be prevented by enhanced regulation?Methods: A discussion of two general approaches is taken: 1) the investigation of mixtures such as smoking or air pollution without specifying the individual agents, and 2) the investigation of individual substances with a focus on possible interactions in the context of dose to receptor. Results: Although mixtures of compounds can have effects, it may not be possible to ascribe causation to a single compound. Furthermore, cumulative low‐dose insult can, in some circumstances, be more toxic than a single high‐dose exposure, e.g. endocrine disruptive effects of a combination of PCBs and dioxins which disrupt the thyroid hormone status; this tends to contradict elements of classical toxicology,. These cumulative insults may further combine with heavy metals and can disrupt the heme synthesis. It is possible that groups of pollutants could be used to test their cumulative capacity to multiple stress‐susceptible receptor targets as is done in smoking and air pollution. This methodology could be used for further groups of potential pollutants, for example those associated with cleaning products, or cosmetics. Testing individual substances with a focus on interactions means that not only chemicals but also concurrent diseases should be taken into account. We suggest that the enhanced regulation of potential multiple stressors falls into two discrete categories. The first comprises a more precautionary approach (as demonstrated by the banning of chemicals such as some brominated flame retardants in Europe). The second comprises a more ‘permissive’ liberal approach involving the initial study of an individual compound, and subsequent interrogation of that compound in combination with another (as demonstrated by lowering the carcinogenicity of aflatoxin by vaccination against hepatitis B). Conclusions: It is n