Leading article: Let's cap bottled water

Our report on the environmental costs of bottling, transporting and marketing drinking water exposes a dilemma for socially responsible consumers. It costs thousands of times more to produce bottled water than tap water, yet, in the industrialised world, this is no safer or healthier. Nor are the costs only financial - there is the impact on the environment of transporting an abundant natural resource, usually by lorry, and the use of millions of plastic bottles.

Yet the fashion for bottled water is only one of the most obvious of the problems of reconciling advanced capitalism with green priorities. At one level, most people are conscious of the unsustainability of flying fresh flowers and baby sweetcorn thousands of miles. At another level, we are happy to enjoy the good things in life that were once the prerogative of the super-rich. How to strike a better, and better-informed, balance between the two is one of the questions to which this newspaper is committed to finding answers.

This requires an open mind and a willingness to confront awkward political realities. We have to challenge some conventional wisdoms, one of the classic examples being the consensus that people should recycle more rubbish. British greens are fond of comparing this country's level of recycling unfavourably with that of Germany. Yet all that proves is that Germany is a more socially disciplined society. In many cases the environmental benefits of recycling are outweighed by the energy used, while the economics of plastics recycling will make sense only when green taxes on petroleum products make the raw material more expensive.

We recognise, too, the electoral obstacles to higher gas and electricity prices in this country, which are the most effective means of saving energy. The headlines generated by British Gas's plans for a 25 per cent price rise would be as nothing if the rise were imposed by politicians in the form of tax. Similarly, we go some way with the Prime Minister in his declaration last week that there is no point in simply "preventing British people getting on planes", because effective action to suppress the growth of air travel would require global cooperation. But Tony Blair suffers an appalling failure of ambition in describing the prospect of any such cooperation as "unrealistic". He cites the fact that the new Airbus is 30 per cent more fuel-efficient, but it is simply not good enough to rely on technological fixes to deal with the problem.

We hope that David Cameron and Chris Huhne, the two new green kids on the block, will come up with the practical policies to change the fiscal incentives for all consumers, green or otherwise, rather than simply dismissing the prospect as "unrealistic".