Evolutionary Health
Co-Evolution of Disease & Living Conditions
Health Effects
What is Risk?
Environmental Risk
Risk Assessment
Risk Abatement
Risk Perception
Risk Management
Uncertainty & Other Features of Risk Assessment
Precautionary Principle
Appendix 1: Contaminants
Appendix 2: Environmnet & Reproductive Health
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Precautionary Principle

One of the main dilemmas in technology design and implementation and the interaction with the environment is our lack of the capability of foresight about long-range and long-term implications. This is evident in the case of the use of pesticides, especially DDT. While DDT helped reduce malaria and saved millions of lives, its overuse left a long-term deadly environmental legacy that we are still trying to understand. Chlorofluorocarbons and ozone depletion, fossil fuel use and global warming, persistence of organochemcials in the environment and the endocrine disruption we are still at a loss to comprehend completely are all results of unforeseen long-term consequences of technological use gone rampant. Philosopher Hans Jonas has called on us to consider the “causal pregnancy” of technology. We now have enough instances to know how the effects of technology, compounded with the complex network that constitutes our environmental system can lead to large negative consequences. So now we are duty-bound to do proactive not just reactive, management of technology.

The Precautionary principle is a philosophy that aims at forestalling disasters. This principle is a “general rule of public policy action to be used in situations of potentially serious or irreversible threats to health or the environment, where there is a need to act to reduce potential hazards before there is a strong proof of harm, taking into account the likely costs and benefits of action and inaction.” (European Environmental Agency. “Late Lessons from Early Warnings: The Precautionary Principle 1896-2000,” EEA, 2001). The EEA Report also points out an example of “precautionary prevention” from London in 1854, when John Snow, a London physician, worked to get the city to remove one pump whose drinking water seemed to be associated with a lot of cases during a cholera epidemic. It was only 30 years later that the German scientist Koch showed that the cholera virus was indeed spread through water polluted by excretion from patients.

The elements of the policies based on Precautionary Principle being promulgated in much of the European Union include:

  • Research and monitoring for the early detection of hazards.
  • A general reduction of the environmental burden
  • The promotion of clean production and innovation
  • The proportionality principle, where the costs of actions to prevent hazards should not be disproportionate to the likely benefits
  • A cooperative approach between stakeholders to solving common problems via integrated policy measure that aim to improve the environment, competition, and employment
  • Action to reduce risks before full “proof” of harm is available if impacts could be serious or irreversible

With an increasing adoption of this precautionary philosophy, we may be moving forward as a society for a better environment and state of health.




  ©Copyright 2003 Carnegie Mellon University
This material is based upon work supported by the National Science Foundation under Grant Number 9653194. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.