Another bright idea down the environmental drain?

Food processing - our cover feature for this issue - has never been far from the headlines over the past few months. Worries over food safety and the increasingly acrimonious and emotional debates over genetically modified crops have increased the public's concern over the food in the shops, on their plates and in their freezers to unprecedented levels.

It was also public pressure - applied via the environmental lobby - that led to the introduction of the oxygenated fuel additive MTBE (methyl tert-butyl ether) in the US in the 1970s; and now, it seems that pressure from the same lobby could see the substance banned (see News Analysis, page 12). The governer of California has announced that MTBE will be phased out as a gasoline additive from 2002 in that state because of problems with the substance leaching into the water supply from leaky storage tanks and marine engines. And when it comes to environmental legislation, where California leads, the rest of the US inevitably follows.

With a sublime irony, it seems that this ban may turn out to be good news for the environmentalists' current number one hate figures: companies producing genetically modified crops. With one oxygenate pushed out of the market, another is badly needed, and the obvious alternative - with known toxicity, simple production process and huge amounts of data on its effectiveness - is ethanol. If it were introduced across the US, demand would rise sharply. The simplest and cheapest way to make ethanol is by fermenting plant cellulose, which could lead to increased demand for corn... and the attractions of modified pesticide-resistant strains could prove overwhelming.

It's part of the history of the chemical industry that products sought to solve a particular problem have ended up becoming problems themselves. The unluckiest industrial chemist of all time, Thomas Midgley, managed to invent both tetraethyl lead as an antiknock agent for petrol and chlorofluorocarbons as aerosol propellants while working for DuPont during the 1930s. Both substances fulfilled all the requirements he was given, and in neither case could the adverse effects be foreseen at the time.

But that was over half a century ago. Knowledge of risk, toxicity and environmental assessments have advanced considerably, which makes it very surprising that the problems with MTBE should only have surfaced and been addressed now.

The worst of it is that this situation could and should have been avoided from the outset. MTBE, which was born out of the environmental lobby, will now be killed off by the environmental lobby. And yet MTBE is doing the job chemical engineers designed it to do. In the rush to find an economic solution under environmental pressure, the possible consequences of its pathway through the environment were overlooked. A complete study should really have foreseen MTBE making its way into water supplies, and warned of all the unpleasant and adverse effects that this might have.