Air Date: Week of July 18, 2003

In San Francisco, vendors and manufacturers must now show their products are environmentally safe before they sell them to the city. Commentator Mark Hertsgaard says the city's adoption of the "precautionary principle" is a big deal.

Transcript

KNOY: San Francisco has become the first city in the nation to let the “precautionary principle” be its guide in environmental decision-making. Commentator Mark Hertsgaard suggests the consequences could be far-reaching and controversial.

HERTSGAARD: In common language, the precautionary principle amounts to “better safe than sorry.” If there’s good reason to think a given technology harms ecosystems or human health, it’s best to avoid that technology in favor of less damaging alternatives - and not wait for irrefutable scientific proof before taking action.

For San Francisco city operations, this is now the law, and it’s a bona fide big deal.

A couple years ago, the city faced a choice: buy more diesel-fueled buses or switch to cleaner, compressed natural gas. Diesel pollution had been linked to children’s asthma, yet, in the end, half of the buses San Francisco bought were diesel. Under the new law, that shouldn’t happen. Or take global warming. The weight of scientific opinion forecasts disastrous consequences if greenhouse gasses aren’t reduced. The precautionary principle would advise shifting to renewable energy now, rather than waiting for the results of further study.

All this is already law in European Union countries. San Francisco following suit has thrilled environmentalists, but reaction from business has been negative. The website for ePublic Relations warns that the precautionary principle will “stifle innovation and progress” in businesses from biotechnology to mining to chemicals. It also asserts that the mere suspicion of harm will be enough to halt a given technology. But the truth is, innovation will simply be channeled in different directions. And San Francisco’s law requires policymakers to evaluate technological alternatives on the basis of “the best science available.”

What the precautionary principle does do—and the reason industry fears it — is shift the burden of proof. Right now, government restricts a technology only after there is definitive proof of harm. So while epidemiologists began linking asbestos to lung cancer in the 1960s, it took 30 years—and an estimated 34,000 deaths—before the government felt it had enough evidence to justify a ban on asbestos. Under the precautionary principle, industry would have to prove its product was safe first rather than letting humans and ecosystems act as guinea pigs.

San Francisco’s law is a modest beginning. It governs only the actions of city government, not businesses or citizens. Its main effect will be on government purchases: fewer toxic chemicals to clean city property, additional limits on pesticide use in parks. Its real significance is the power of example. The precautionary principle aims to stop environmental harm before it starts. If that simple, yet radical, idea comes to dominate policy making in the United States, the effect could be nothing short of revolutionary.

KNOY: Commentator Mark Hertsgaard is the author of “The Eagle’s Shadow: Why America Fascinates and Infuriates the World.”