One in four deaths worldwide can be linked to pollution and other environmental damage caused by humans, the United Nations has warned.

Polluted drinking water, filthy air and land destroyed by “mega-farms” are among the threats that must be urgently addressed, according to a new report compiled by hundreds of scientists.

Based on data from 2015, they estimated 9 million deaths each year can be attributed just to pollution – with outdoor and indoor fumes posing the biggest danger.

The report’s authors warned humanity faces a “bleak future”, as parts of Asia and Africa, in particular, could see millions more premature deaths in the coming decades.

The gap between rich and poor countries is expected to grow as overconsumption and food waste in the developed world are matched by hunger and the spread of preventable diseases elsewhere.

Pollutants entering freshwater systems could lead to anti-microbial resistance becoming the number one cause of death by the middle of the century as infections become harder to control.

The most polluted towns and cities in the UK Show all 25 1 /25 The most polluted towns and cities in the UK The most polluted towns and cities in the UK 25. Middlesbrough 11 micrograms per cubic metre. A report from the World Health Organisation has given figures for fine-particle air pollution across the world. Here follow the 25 most polluted towns and cities in the UK The most polluted towns and cities in the UK 24. Derry 11 micrograms per cubic metre Getty The most polluted towns and cities in the UK 23. Hull 11 micrograms per cubic metre (estimate) Getty The most polluted towns and cities in the UK 22. Coventry 11 micrograms per cubic metre Getty The most polluted towns and cities in the UK 21. London 11 micrograms per cubic metre PA The most polluted towns and cities in the UK 20. Stoke-On-Trent 12 micrograms per cubic metre Getty The most polluted towns and cities in the UK 19. Sheffield 12 micrograms per cubic metre (estimate) Getty The most polluted towns and cities in the UK 18. Sandy, Bedfordshire 12 micrograms per cubic metre Google The most polluted towns and cities in the UK 17. Royal Leamington Spa 12 micrograms per cubic metre Getty The most polluted towns and cities in the UK 16. Prestonpans 12 micrograms per cubic metre Richard Webb The most polluted towns and cities in the UK 15. York 12 micrograms per cubic metre Getty The most polluted towns and cities in the UK 14. Plymouth 12 micrograms per cubic metre Getty The most polluted towns and cities in the UK 13. Nottingham 12 micrograms per cubic metre Getty The most polluted towns and cities in the UK 12. Eccles 12 micrograms per cubic metre (estimate) Rept0n1x The most polluted towns and cities in the UK 11. Grays 12 micrograms per cubic metre (estimate) Getty The most polluted towns and cities in the UK 10. Liverpool 12 micrograms per cubic metre Getty The most polluted towns and cities in the UK 9. Leicester 12 micrograms per cubic metre Getty The most polluted towns and cities in the UK 8. Leeds 12 micrograms per cubic metre Getty The most polluted towns and cities in the UK 7. Chepstow 12 micrograms per cubic metre Getty The most polluted towns and cities in the UK 6. Carlisle 12 micrograms per cubic metre The most polluted towns and cities in the UK 5. Gilllingham 13 micrograms per cubic metre Philip Halling The most polluted towns and cities in the UK 4. Swansea A view of Swansea centre taken from Kilvey Hill January 2016 Getty The most polluted towns and cities in the UK 3. Manchester Manchester, UK - November 24, 2016: View of Manchester city center. Tall buildings an be seen on either side of the road and a tram can be seen passing. People can be seen walking on the pavements. Getty The most polluted towns and cities in the UK 2. Gibraltar Wide view of the rocks of gibraltar from the observation deck Getty The most polluted towns and cities in the UK 1. Scunthorpe Scunthorpe, UK - October 19, 2015. TATA steels' Scunthorpe plant in England which has recently been saved from closure after being bought by the investment firm Greybull Capitla for Â£1. Getty

The UN released its Global Environment Outlook, a project six years in the making, at a major meeting in Nairobi on Wednesday.

It draws on hundreds of data sources to establish various factors driving the prevalence of more than 100 diseases.

The report concluded preventable environmental problems will “cause approximately 25 per cent of global disease and mortality”.

“The science is clear. The health and prosperity of humanity is directly tied with the state of our environment,” said Joyce Msuya, acting executive director of UN Environment.

“We are at a crossroads. Do we continue on our current path, which will lead to a bleak future for humankind, or do we pivot to a more sustainable development pathway? That is the choice our political leaders must make, now.”

The Paris climate agreement was established in 2015 as a strategy to address climate change, with nations committing to cut their carbon emissions and hold back soaring global temperatures.

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But while awareness of climate change’s catastrophic impacts grows, there is no equivalent agreement by nations to deal with the other environmental challenges facing the planet.

Negotiations taking place at the current UN environment assembly are expected to focus on critical issues including tackling food waste and plastic pollution in the oceans.

However, the team behind the new report said that most of the policies and technologies that can help avoid the worst already exist.

“What is currently lacking is the political will to implement policies and technologies at a sufficient speed and scale,” said Joyeeta Gupta, who co-led the report’s production.

According to their analysis, investing 2 per cent of each nation’s GDP would ensure economic growth continues while avoiding much of the impact of climate change, water loss and habitat destruction.