Britain is becoming a nation of "chemiphobes" - people with an irrational fear of chemicals - the Hay festival was told yesterday.

So tainted is the public view of chemicals and the industry that produces them that before long the numbers of scientists training as chemists will dwindle, putting pressure on the industry to relocate to other countries, according to John Emsley, the author of Vanity, Vitality and Virility: The Science Behind the Products You Love to Buy.

Dr Emsley, whose talk at the festival examined the chemicals in products such as lipstick, nappies and Viagra, warned that chemistry had suffered a backlash thanks to high-profile disasters such as thalidomide and DDT poisoning.

But while the chemical industry has since become more safety-conscious, widespread fear of chemicals among the general public has spiralled out of control.

"To most people, the word 'chemical' now means toxic, polluting and harmful, but that's sheer ignorance," he said.

This month, the Royal Society of Chemisty called for chemists to be more willing to engage with the public.

"So many scare stories are published and much of the reason is some chemists feel that no matter what they say, it's going to be spun in a way they're not going to like," Dr Emsley said.

Chemistry is already facing a crisis in Britain, where the number of students studying it at university has dropped by 25% from an all-time high seven years ago.

"If we're not careful, we're going to lose the goose that lays the golden eggs," Dr Emsley said.

Others at the forefront of chemistry agree. David Giarchardi, the chief executive of the Royal Society of Chemistry, said: "If we can't reverse this sentiment, there's a real risk that the basic chemical industry will move east to China and India, while the pharmaceutical industry will move west to the US."