The gist: There are some 85,000 synthetic chemicals approved for commercial use today, but few have been tested for their effects on human health. We need to test them before putting them into widespread use.

The details: Simply stated, the precautionary principle is a policy of "proving safety first" with new chemicals--testing them for harmful health effects before putting them into widespread use.

There are some 85,000 synthetic chemicals approved for commercial use today, but few have been tested for their effects on human health. Take the case of PBDEs, chemicals widely used as toxic flame retardants in everyday products such as computers and foam padding.

• Numerous studies--including one by Sightline Institute--have detected increasingly high levels of PBDEs in the environment, in fish and orcas, and in people.
• Laboratory studies indicate that PBDEs, which are structurally similar to PCBs, impair neurological functioning in mice and rats, even at very low levels.
• If PBDES had been tested before industry began using them, their health effects might have been identified, and safer alternatives could have been used instead.

The European Union, California, and some Northwest states are now taking action to phase out PBDEs. This belated response is encouraging, but it is not proof of how well our region secures itself from the effects of toxic chemicals.

It's actually another in a long string of tragic cases-lead, arsenic, asbestos, DDT, PCBs, dioxins, and many others-that demonstrate our society's failure to look before it leaps. By the time the evidence of a compound's harm is clear, it is often too late.

If the precautionary principle were adopted, manufacturers would be responsible for doing safety tests on a compound before it's used in commerce--just as the national governments of the United States and Canada already do for new medicines and food additives. And society would do a better job of protecting human health and the environment.

One example of the precautionary principle in practice is Europe's new REACH program, which would shift responsibility for testing chemicals from governments to manufacturers. Manufacturers will provide safety data for some 30,000 chemicals.

Outside resources

Commonweal - description of the precautionary principle

Science and Environmental Health Network's resource page on the precautionary principle