Health experts have called for action to deal with the one in four homes and schools in South Africa that they say are coated with lead-based paint.
In an article in the latest SA Medical Journal, experts from the Medical Research Council (MRC) said tests should be carried out to identify high-risk buildings.
"Provision should be made for the safe management of lead-based paint in the worst-affected dwellings and schools using a combination of in-place containment and more permanent removal methods," they said.
Lead linked to delinquent behaviour
They also said that given the link between lead exposure, poor school performance and delinquent behaviour, it was "extremely important" for South Africa to set standards for children's blood lead levels, and to develop ways of responding to high levels.
Research was needed on the use of lead in various forms in cottage industries, and in traditional cultural practices, including medicines.
They said though lead reduction programmes had been launched in South Africa - including the elimination of lead in fuel - lead still had a significant health impact.
They said a survey in an informal settlement in the Durban metropolitan area had shown that half of the children there had a blood lead concentration of above ten micrograms per decilitre of blood.
That level, they said, was associated with "considerable health risk".
Lead can lead to bad health
Lead exposure can lead to gastrointestinal problems, anaemia, stunted growth, nerve disorders, behavioural and cognitive problems, hearing loss and death.
The MRC warning follows last week's worldwide recall of Chinese-made toys found to have been coated with lead-based paint.
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