The human toll in Ivory Coast's toxic waste scandal rose sharply from 1,500 to more than 5,000 people contaminated by open-air dumping sites in Abidjan, the health ministry said.
Three people, all children, have also died from the poisoning.
"By yesterday we had counted more than 5,000 people in health centres" for problems linked to the toxic poisoning, the ministry's spokesman Simeon N'Da told AFP.
"The number of deaths remains unchanged at three," he added.
Ivory Coast's entire cabinet resigned on Wednesday over the poisoning scandal -- which triggered angry protests -- and an inter-ministerial committee was set up to handle the crisis.
Six French waste disposal experts arrived in Ivory Coast on Friday to help the skeleton administration, which has announced an emergency plan to neutralize toxic fumes emanating from the waste.
The toxic material was dumped in August by a Panamanian-registered ship onto about 10 open-air sites in the commercial capital Abidjan, a city of four million people.
Environmental pressure group Greenpeace said it comprised 400 tonnes of oil refining waste, rich in organic matter and poisonous elements. The latter include hydrogen sulphide and organochloride, which can cause nausea, rashes, fainting, diarrhoea and headaches.
The Greek company that owns the vessel, Prime Marine Management, confirmed the waste had been discharged but said the action was lawful.
The "Probo Koala" was chartered by a Netherlands-based company, which says an Ivorian firm had been entrusted with handling the unloaded waste.
Ivory Coast Prime Minister Charles Konan Banny, who has been asked to form a new government, has accused his disgraced administration of "negligence" and promised to punish those responsible.
The scandal has added to the woes of this west African state, where a UN-brokered peace process has tried to end four years of political crisis touched off by a failed coup against President Laurent Ggabgo in 2002 that effectively split the country in two.
Banny toured one of the waste dumps with French Junior Aid Minister Brigitte Girardin on Friday. Both wore gas masks to protect themselves from the noxious fumes emanating from the black, oily sludge, which has now been closed off by a security fence.
Girardin denounced the dumping as "criminal and unacceptable", in comments Saturday after arriving in Brazzaville for separate talks with officials there.
The sludge had contaminated nearby streams and pools and burnt the grass. But locals continued to grow tomatoes nearby, telling reporters they were now used to a smell described by one resident as "like gas mixed with garlic."
- 116 Human Rights
- 182 Health