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Ecosystems and Human Health - Chapter 2

chapter two Risk analysis and public perceptions of risk (Risky Business) Introduction It is estimated that between 60,000 and 70,000 industrial and commercial chemicals are currently in use in North America, with the possibility of more coming on-stream every day. Only about 3500 of these have been studied sufficiently to conduct any sort of risk assessment regarding human health, and such studies characteristically use only one route of administration (portal of entry). Approximately 600 chemicals are currently judged to constitute a significant potential risk to human health, either because of their toxicity or because they are manufactured in such quantities that there is likely. | chapter two Risk analysis and public perceptions of risk Risky Business Introduction It is estimated that between 60 000 and 70 000 industrial and commercial chemicals are currently in use in North America with the possibility of more coming on-stream every day. Only about 3500 of these have been studied sufficiently to conduct any sort of risk assessment regarding human health and such studies characteristically use only one route of administration portal of entry . Approximately 600 chemicals are currently judged to constitute a significant potential risk to human health either because of their toxicity or because they are manufactured in such quantities that there is likely to be a high level in the environment. The public seems unwilling to give up the advantages accruing from such chemicals plastics pesticides petroleum fuels etc. but is also increasingly vociferous in its demands to be protected from any adverse effects arising from their use. The environmental damage caused by some of these agents is becoming more and more evident and indeed this may be the real danger facing humankind. Nevertheless legislators and regulators are faced with the task of making decisions regarding safe limits for thousands of chemicals often on the basis of very limited data and in the face of pressure from consumer groups environmental activists and industry lobbies. Assessment of toxicity vs. risk Toxicity assessment is the determination of the potential of a substance to act as a poison the conditions under which this potential will be realized and the characterization of its action. Conversely the assessment of risk involves the quantitative assessment of the likelihood of these deleterious effects occurring in a given set of conditions. This subtle difference is not 2001 CRC Press LLC always appreciated by the public and especially not by the news media. Thus statements frequently appear to the effect that dioxin is the most potent poison known to man. In fact botulinum .