Scientific knowledge is a precious thing. Yet the times when scientists most want to share it often coincide with a selective deafness amongst policymakers, and George W Bush’s administration has become notorious for shunning scientific advice. In recent years the US Environmental Protection Agency (EPA) has come under fire for the same habit, and October saw yet another example, involving the EPA’s approval of methyl iodide as a pesticide. The compound is intended to be a substitute for methyl bromide, widely used as a soil fumigant by strawberry growers until it was slated for phase-out under the Montreal Protocol: its labile bromine atom is about 50 times more likely to destroy upper-atmosphere ozone than the chlorine atoms in CFCs that were long ago removed from my spray-on deodorant. Yet despite having had more than a decade to search for suitable alternatives, an annual plea for ’critical use exemption’ has allowed methyl bromide use to continue.

Methyl iodide is kinder to the ozone layer - but as a pretty reactive methylating agent, it may not give farmworkers’ DNA such an easy ride. A high-profile letter to the EPA from 54 top scientists - including Roald Hoffmann, Bob Grubbs, and William Knowles - raised concerns and asked for an independent review of the case, with no success. 

Still, despite the EPA’s approval, methyl iodide must also get the nod from state agencies before farmers can start fumigating - and since California is home to most of America’s strawberry farms, that may not happen in a hurry. The state has a strong track record on environment issues, and last month governor Arnold Schwarzenegger passed into law a ban on certain phthalates used in children’s toys and teething rings. 

The bill provoked a dismayed reaction from the American Chemistry Council, the trade association for chemicals manufacturers. ’This law is the product of the politics of fear,’ thundered ACC president Jack Gerard. ’Thorough scientific reviews in this country and in Europe have found these toys safe for children to use.’ In fact, extensive reviews of scientific evidence by the European Commission resulted in a ban on phthalates such as di(2-ethylhexyl) phthalate, a PVC plasticiser, in 2005. Many US toy manufacturers voluntarily followed suit. The European decision may have been conservative, but it was certainly not without scientific basis. 

These two contrasting cases show how chemists can seek to influence the way their vocation is seen by the rest of the world. This is true whether lobbying government, or simply having a conversation. For example, Sense About Science, a UK science advocacy group, recently launched a campaign to encourage scientists to debunk the pseudoscience that pervades marketing material (see p43). They’re calling for young chemists to take a stand for their science, using grass-roots action to challenge ridiculous claims and drive the reflexive fear of ’chemicals’ out of public life. 

Of course, the tone - collaborative, not prescriptive; inclusive, not patrician - is crucial to winning acceptance. Despite the EPA’s decision over methyl iodide, the campaigning chemists have won substantial public support for their stand - unlike the ACC. 

Both cases present clear opportunities for chemistry to save the day. Constantly hunting for safer, cleaner alternatives to existing products is one of the things that chemists do best, and it’s an important message to deliver. Improving our surroundings presents an opportunity to be the heroes, not the villains of the piece - if the rhetoric is right.

Mark Peplow, editor