Delegates from some 120 nations met in Kenya on Monday to tackle the growing global threat from hazardous waste including toxic chemicals, obsolete electronics and rust-bound ships and aircraft.
The main focus of five days of talks is the mounting problem of so-called "e-waste" - obsolete computers, mobile telephones and televisions shipped mostly to the developing world, where many are dumped and burned at open air sites.
"We have managed to create yet another problem on this planet," Achim Steiner, head of the UN Environment Programme (UNEP), said at the opening of the conference, which gathers parties to the Basel Convention that monitors hazardous waste.
Proposals on the table this week include making manufacturers take financial responsibility for their products, from the design stage to final disposal. Delegates will also seek to tighten international waste regulations to prevent a repeat of the disaster in Ivory Coast in August, when 10 people were killed after toxic petrol "slops" were tipped around its main city Abidjan.
Participants will also discuss what to do about a huge growth in the number of "hyperbulk" items - mostly old planes and ships - due to be scrapped over the coming years. According to new figures published by UNEP, almost a third of the 25,000 large civil aircraft now in service will be dismantled in the next 10 to 15 years. The number scrapped is expected to increase to more than 35,000 by 2035, it says.