Estimating the burden of disease attributable to lead exposure in South Africa in 2000

Abstract

Objectives: To estimate the burden of disease attributable to lead exposure in South Africa in 2000.

Design: World Health Organization comparative risk assessment (CRA) methodology was followed. Recent community studies were used to derive mean blood lead concentrations in adults and children in urban and rural areas. Population-attributable fractions were calculated and applied to revised burden of disease estimates for the relevant disease categories for South Africa in the year 2000. Monte Carlo simulation-modelling techniques were used for the uncertainty analysis.

Setting: South Africa.

Subjects: Children under 5 and adults 30 years and older.

Outcome measures: Cardiovascular mortality and disability-adjusted life years (DALYs) in adults 30 years and older and mild mental disability DALYs in children under 5 years.

Results: Lead exposure was estimated to cause 1,428 deaths (95% uncertainty interval 1,086-1,772) or 0.27% (95% uncertainty interval: 0.21 - 0.34%) of all deaths in South Africa in 2000. Burden of disease attributed to lead exposure was dominated by mild mental disability in young children, accounting for 75% of the total 58,939 (95% uncertainty interval 55,413 - 62,500) attributable DALYs. Cardiovascular disease in adults accounted for the remainder of the burden.

Conclusions: Even with the phasing out of leaded petrol, exposure to lead from its ongoing addition to paint, para-occupational exposure and its use in backyard 'cottage industries' will continue to be an important public health hazard in South Africa for decades. Young children, especially those from disadvantaged communities, remain particularly vulnerable to lead exposure and poisoning.