The international community must meet the costs of cleaning and restoring sites in Ivory Coast contaminated by toxic waste, the UN says.
Authorities ordered the burning of pigs who had eaten the waste
The UN Environment Programme (Unep) says millions of dollars are needed.
Reports from Abidjan say an official inquiry blames the August toxic waste spill on negligence and corruption.
The UN recommendation comes on the eve of a conference on the Basel Convention, designed to regulate international trade in toxic waste.
"One of the important lessons from the situation in Abidjan is that we have a serious problem with enforcement," said Basel Convention Executive Secretary Sachiko Kuwabara-Yamamoto.
"National and international laws are in place to regulate these exports, but problems arise because of the lack of legal and technical institutional capacity in many developing countries to monitor traffic across their borders."
Duty to pay
The Ivory Coast incident first came to light in early September, when residents of Abidjan found themselves affected by noxious fumes produced by waste dumped several weeks before at sites around the capital.
At least 10 people died, and more than 70,000 sought medical treatment. As citizens mounted demonstrations over the issue, Prime Minister Charles Konan Banny dissolved his cabinet.
Employees of the Dutch Trafigura company, accused of sending the waste to Ivory Coast, have been attacked in their Abidjan prison cells. Legal cases are continuing to establish responsibility.
According to the AP news agency, a commission of inquiry convened by the Ivorian government has blamed negligence and corruption by senior officials.
The agency says ministers granted a licence to a Nigerian businessman who set up a company, called Tommy, specifically to accept the waste. No evaluation of the company's capacity was asked for, it says.
The Ivorian authorities estimate the costs for cleaning up and restoring the contaminated sites at about $30m; and Unep says the international community has a duty to pay.
"Irrespective of who will or who will not be held liable for this incident, it is the people of one of the world's poorest countries who are now being forced to pay the bill for removal and clean-up operations," said Unep Executive Director Achim Steiner.
"We must assist Ivory Coast now."
The UN appeal came as representatives of more than 160 countries gathered at Unep headquarters in Nairobi for negotiations on the Basel Convention on the Transboundary Movements of Hazardous Wastes and their Disposal.
This treaty is designed, among other things, to stop incidents like the toxic waste tragedy in Abidjan from occurring.
Although the basic Convention is now enshrined in international law, many of its measures remain un-ratified, notably the Liability and Compensation Protocol which would force parties to accept financial liability for breaches of the Convention.
The main focus of the Nairobi meeting is e-waste, the export of used computers, mobile phones, televisions and other electronic equipment to the developing world.
In major developing countries, including India and China, workers dismantle and dispose of these goods in conditions hazardous to their health.