Numbers of UK students applying to study chemistry at university have plunged by more than 20% over the past three years, new figures show.

The fall has alarmed business leaders, who say homegrown talent is needed to run Britain’s chemistry industry, which is worth more than £50bn a year to the UK economy.

As a result, an open letter – signed by companies such as drugs maker AstraZeneca and chemicals group BASF – has been sent to the government, calling for urgent action to encourage school leavers and students to follow careers in chemistry.

“This is a matter of significant concern for a number of sectors deemed crucial to the country’s economy,” the letter states. “From finding solutions to climate change and decarbonising transport to finding new drugs or even creating novel materials, chemistry is too important to let slide.

“What is urgently needed is a clear strategy and action plan to articulate the diversity and excitement of a career in chemistry as well as the wider science community to our young people.”

According to the Royal Society of Chemistry, figures show the number of UK students applying to study the subject dropped by 21% between 2015 and 2018, despite an increase in students sitting A-level chemistry.

“It is concerning that some A-level students may not understand the opportunities chemistry can offer them, at a point where they’re making crucial career decisions,” said Danièle Gibney, the society’s education policy manager. “The UK’s problem appears to be our inability to provide enough careers advice to help them make informed choices about their further education and career aspirations.”

Gibney added that chemistry was key to tackling the world’s most pressing problems, from pollution to antibiotic resistance. “In an era where young people aspire to influence the world, chemistry offers the opportunity to do so in a meaningful and important way.”