Doctors Without Borders have said that Nigeria has provided nearly $3 million in long-delayed financing to clean up part of an area where lead poisoning has killed hundreds of children.
The lead poisoning crisis in northwest Zamfara state that first came to light in 2010 was called the worst such epidemic "in modern history" by Human Rights Watch, with an official death toll saying 400 children were killed across the state.
The government in Nigeria, Africa's largest oil producer, has come under mounting pressure from activists to release the funds, saying more children's lives were at risk.
The $2.7 million (two million euros) that Nigeria has made available will be spent cleaning up the village of Bagega, one of the hardest hit areas, where up to 1,500 children are suffering from lead poisoning, Ivan Gayton of France-based Doctors Without Borders (MSF) told AFP.
Gayton said the other seven villages affected by the epidemic had been cleared of toxic material.
"The federal government, through the ministry of environment, has made available $2.7 million needed to begin the remediation in Bagega village in Zamfara state and we expect to begin the exercise on Monday," Gayton told AFP.
In November, MSF released a report that said the contaminated soil in Bagega needed to be removed before the rainy season starts in April, warning of potentially "disastrous" consequences if rainfall caused the hazardous material to spread further.
"We've been sounding the alarm increasingly since November," Gayton said.
Clean up, known as remediation, cannot be carried out during the rainy season and treatment can only begin once remediation is complete.
Lead was dispersed in several Zamfara areas by the processing of ore for gold extraction using unsafe mining techniques. Illicit gold mining is more lucrative than agriculture for the impoverished farming communities.
Local communities had initially largely concealed or denied the fatalities and illnesses from lead poisoning for fear that authorities would ban their mining activities.
Gayton said that when the cleanup is complete, additional funds will be needed to put in place safer mining practices.
Most Nigerians live on less than $2 per day despite the oil wealth in the country, which has long been held back by corruption and mismanagement.