Air pollution in the UK is costing more than £500m a week in ill health, NHS care and productivity losses, with 99% of the population breathing in “toxic air”, doctors have said.

Dirty air is killing more than 500 people a week, with health harm to almost every organ of the body caused by air pollution, even at low concentrations, the Royal College of Physicians (RCP) said.

With an impact on mortality and healthy life expectancy, the effects on individuals, society, the economy and the NHS were huge and the threat air pollution posed to public health was greater than previously understood, a landmark report by the college concluded.

The RCP report also highlighted studies providing new information about the significant health dangers of toxic air, including foetal development and risk of cancer, heart disease, stroke, mental health conditions and dementia.

Air pollution in the UK now kills 30,000 people and costs £27bn a year, according to the research, which also said there was no safe level of air pollutants. The figure could even be significantly higher – up to £50bn – if wider impacts such as dementia were taken into account.

Exposure to air pollution can shorten people’s lives by 1.8 years, “just behind some of the leading causes of death and disease worldwide”, including cancer and smoking, the report added.

The college called for action from the government to tackle the crisis, as it urged ministers to “recognise air pollution as a key public health issue”.

In the foreword of the report, England’s chief medical officer, Prof Chris Whitty, said: “Air pollution remains the most important environmental threat to health, with impacts throughout the life course.

“It is an area of health where the UK has made substantial progress in the last three decades, with concentrations of many of the main pollutants falling rapidly, but it remains a major cause of chronic ill health as well as premature mortality.”

Dr Mumtaz Patel, the president of the RCP, said air pollution could no longer be seen as just an environmental issue because it was now “a public health crisis”.

“We are losing tens of thousands of lives every year to something that is mostly preventable and the financial cost is a price we simply cannot afford to keep paying.”

She added: “We wouldn’t accept 30,000 preventable deaths from any other cause. We need to treat clean air with the same seriousness we treat clean water or safe food. It is a basic human right – and a vital investment in our economic future.”

The report came as a separate report by Asthma and Lung UK found air pollution had triggered potentially life-threatening asthma attacks or serious flare-ups of illness in one in five people with lung conditions.

The charity’s chief executive, Sarah Sleet, said air pollution had become a public health emergency and was “the biggest environmental threat to human health”.

“Despite the huge personal and financial costs of air pollution, the government has not yet shown the political will to tackle this crisis.”

On Thursday, doctors, nurses, patients and activists will meet at Great Ormond Street children’s hospital in London and walk to Downing Street to deliver a letter calling on ministers to commit to “ambitious” air quality targets.

Next month a cross-party group of MPs will reintroduce a bill, named after a nine-year-old schoolgirl who died from an asthma attack linked to air pollution, which aims to make clean air a human right under UK law.

Called “Ella’s Law”, the proposed legislation is named after Ella Adoo-Kissi-Debrah, who lived 82ft from the busy South Circular Road in Lewisham and suffered a fatal asthma attack in 2013. She became the first person to have air pollution listed as a cause of death after a landmark inquest in 2020.

The government said it was committed to tackling air pollution across the UK.

A spokesperson added: “We have already provided £575m to support local authorities to improve air quality and are developing a series of interventions to reduce emissions so that everyone’s exposure to air pollution is reduced.”