They promised to curb plastic and chemical contamination of the air, soil, rivers and oceans.
The world's nations vowed on Wednesday to curb plastic and chemical contamination of the air, soil, rivers and oceans, requiring a complete overhaul in the way goods are produced and consumed.
Changing the behaviour of producers and buyers would be key to achieving the vision of a "pollution-free planet" outlined in a political declaration adopted at the third UN Environment Assembly (UNEA).
"Pollution is cutting short the lives of millions of people every year," said the call to action issued by government ministers in Nairobi at the world's highest-level decision-making forum on environmental issues.
"Every day, nine out of 10 of us breathe air that exceeds WHO (World Health Organization) guidelines for air quality and more than 17,000 people will die prematurely because of it," the declaration added.
It committed governments to promoting "sustainable economic productivity", and to encouraging more "sustainable lifestyles" by making it easier to reuse and recycle products, thus reducing waste.
"What we need to do next is to move concretely to a plan of action," UN Environment Programme deputy head Ibrahim Thiaw told journalists on the final day of the December 4-6 pollution-themed gathering.
All 193 UN states are members of the UNEA.
"Some of the actions will have to do with the way we produce and the way we consume," Thiaw said.
"Our models of production and consumption will have to change. We do not have to have models of production and consumption that harm the environment and keep killing us."
This would require "very clear policies" from governments at the national and local level, said Thiaw, such as banning single-use plastic shopping bags.
Mobile phones could be upgraded and reused instead of being replaced every few years, and plastic straws prohibited, for example.
"Every year we dump 4.8 to 12.7 million tonnes of plastic in our oceans and generate over 40 million tonnes of electronic waste," the ministerial declaration said.
The UN Environment Programme said it had received 2.5 million anti-pollution pledges, including from national governments, municipalities, businesses and individuals by Wednesday.
They include commitments, which are non-binding, to ban plastic bags, curb air pollution, or green public transport.
Some 88,000 individuals also made pledges, undertaking to switch to less-polluting fuel, for example, or to use less plastic and recycle more.
Taken together, if all the commitments by governments, businesses and civil society are honoured, they would lead to 1.4 billion people breathing clean air, said Jacqueline McGlade, who co-authored a pollution report for the assembly.
Furthermore, 480,000 kilometres (almost 300,000 miles) — a third of the world's coastlines — will be unpolluted, and $18.6 billion dollars (15.7 billion euros) will be invested in anti-pollution research and innovation.
The assembly heard this week that pollution has become the biggest killer of humans, claiming nine million human lives every year — one in six deaths worldwide.
Of the annual tally, nearly seven million people succumb from inhaling toxins in the air — from car exhaust fumes, factory emissions and indoor cooking with wood and coal, according to a recent report by The Lancet medical journal.
Lead in paint alone causes brain damage in more than half-a-million children every year.
The assembly adopted a dozen pollution-curbing resolutions — urging governments to ban the use of lead in paint, step up "actions" to prevent and significantly reduce marine pollution of all kinds by 2025, and urging member states to set ambitious air quality standards.
The president of the UNEA meeting, Costa Rica's environment minister Edgar Gutierrez, lamented on Wednesday that humans "haven't done a good job" managing Earth's natural bounty.
"The room we have for making more mistakes is very narrow," he warned.
Environmental group Greenpeace welcomed the assembly outcome, stressing the resolutions must now be put into action.
"Whilst leaders talk, the tide of plastic, chemicals and air pollution keeps growing," Greenpeace East Asia campaigner Cheng Qian said in a statement.
"The decisions made here must be actioned, implemented and accelerated if we are to stand a chance of restoring the health of our planet."