Lead is a naturally occurring toxic metal found in the Earth’s crust whose widespread use has resulted in extensive environmental contamination, thus making it a public health threat.^1,2,3 The various uses of lead include use in petrol, paint, playgrounds, toys, households, glass, cellular phones, computers, protective clothing, candles and cosmetics.^4,5,6 There is no level of exposure known to be without harm in both adults and children, but children are particularly vulnerable and can absorb four to five times as much ingested lead as adults.¹ The history of lead distribution in the human environment and its recognition as a neurotoxin spans over 2000 years,⁵ and yet there are countries with no regulations for lead in paint.⁷ Lead is neurotoxic and even low levels of exposure in childhood can result in reduced intelligence, increased intellectual disability rates, lower educational attainment and reduced future earnings.^8,9,10,11,12 Lead affects all body systems and can cause anaemia, growth stunting and renal and cardiovascular diseases later in life.^{8,11,12,13,14}

One of the most well-evidenced and feasible sources of childhood lead poisoning to address is lead paint.¹⁵ Lead paint is a primary source of lead poisoning globally and is widespread in Africa.^3,6,11,16,17 There has been no research to date investigating whether paint is a source of lead exposure in Zimbabwe. Zimbabwe currently has no lead paint.⁷

Table 1 summarises the lead concentration data for the paint samples in Zimbabwe and Botswana. Seventy percent of paint samples from Zimbabwe were above 90 ppm, presenting significant health risks and were above the limit suggested by the World Health Organization (WHO) and United Nations (UN).^15,19 Sixty percent of samples were above the higher limit of 600 ppm, and 20% of samples were above 10 000 ppm, indicating an extremely high lead concentration. Regarding the samples from Zimbabwe, the mean concentration was 4863 ppm, the median concentration was 6900 ppm and the maximum concentration was at 12 000 ppm.

All the 19 paint samples from Botswana were found to be below the laboratory reporting limit. Of the seven brands tested, six were manufactured in South Africa, which had a 600 ppm lead paint law in place.⁷

Figure 1 compares the results of this study to previous studies in Southern Africa.¹⁷ Zimbabwe and Botswana had the highest and lowest rates of lead for the group, respectively. Botswana had the lowest ‘exceedance’ rates (the proportion of samples above a given limit) for the group at 90 ppm, 600 ppm and 10 000 ppm limits. Zimbabwe had the highest exceedance rates for the group at 90 ppm and 600 ppm limits and the second-highest exceedance rate at the 10 000 ppm limit.

The lead content of samples from Zimbabwe was greater in coloured paints. All white or cream paint samples (n = 2) did not have lead content above 90 ppm. All (100%) of red, yellow or orange (n = 6) samples were above 90 ppm. Fifty percent of green samples (n = 2) were above 90 ppm.

Three samples made claims of no added lead on can labels, but two of these had lead concentrations of 6900 ppm. Of the seven samples with no claims about lead content on labels, five had lead concentrations over 90 ppm.

This study found high levels of lead in a majority of paints and brands sampled in Zimbabwe. The average and median concentration of all paints tested was over 50 times the recommended regulatory limit of 90 ppm and sufficient to present serious health risks.¹⁵ Some tested paints were above 10 000 ppm, an extremely high level that presents even greater health risks.

However, the study also found that 30% of Zimbabwean samples had lead concentrations below 90 ppm. These samples included both white and coloured paints and were manufactured in Zimbabwe. These results suggest that producing and selling lead-free paint is possible in Zimbabwe.

These results support previous studies, which have found that white paint is less likely to contain lead.¹⁶ This finding suggests that lead is being added to paint in Zimbabwe as a pigment.³ Transitioning to non-lead pigments is both feasible and cost-effective.¹⁵

False claims of ‘no added lead’ were identified in this study. Mandating clear warnings and verified lead-free claims will be an important part of any future regulatory solution.

Paints available in Botswana do not appear to contain high concentrations of lead. However, lead paint may still be present on existing structures. Botswana does not regulate lead paint, so there are no barriers to lead paint entering the market through local producers or importation. Botswana’s positive results are likely because six out of the seven brands were imported from South Africa, which does regulate lead paint. This is a fragile solution, and a more robust remedy would be for Botswana to introduce lead paint regulation.

Regulating the presence of lead in household paints is a clear and effective path to reduce lead exposure.³ Regulation that limits lead concentrations in paint to below 90 ppm is a global standard and already in place in 79 countries.⁷

This study was limited by its small sample size, only including 10 paints in Zimbabwe and 19 paints in Botswana. Nevertheless, given that all main brands available in the largest city of each country were represented, it is likely that larger studies of the paint market would corroborate our key finding of excessive lead in Zimbabwe’s paints. Our study is also limited by its focus on paint currently available on the market. Field studies of the lead content of paint on existing surfaces in Zimbabwe and Botswana would further inform the extent to which lead paint is a source of exposure in the two countries.

This study demonstrates for the first time that some solvent-based paints sold in Zimbabwe contain extremely high levels of lead, suggesting that paint may contribute to lead exposure in the Zimbabwean population. A larger study may provide a clearer picture of the size of the problem, the effects thereof and the need for regulation.