Safety concerns of lead chromate in enamel paints: A study based on the Sri Lankan enamel paints industry after the lead paint regulatory enforcement

Although lead (Pb) paint testing has been carried out in a large number of studies in Sri Lanka, little work appears to have been done to investigate the chromium (Cr) levels, variation of Pb and Cr levels through different production batches of paint manufacturers and the possible sources of unusually higher Pb and Cr levels in paints. Thirty-six enamel paints manufactured after the lead paint regulatory enforcement, were randomly purchased from six popular brands in Sri Lanka to assess their Pb and Cr levels. Heavy metals in liquid paints were acid digested for the analysis by flame atomic absorption spectrometry (FAAS). From the thirty-six paints analysed (six colours from six brands) one yellow and one green paint showed highest Pb and Cr levels. Reported Pb levels in yellow and green paints were 11545 ± 6 ppm and 4060 ± 9 ppm and Cr levels were 2681 ± 2 ppm and 960 ± 7 ppm, respectively. These yellow and green paints were labelled as safe although they exceeded the Pb regulatory limit. Pb and Cr in the other 34 samples were below Sri Lankan regulatory limits. For paints with both Pb and Cr, Pb and Cr mole ratio was 1.079:1, suggesting the possible presence of lead chromate (PbCrO4) in certain paints although the manufactured paints adhered to safety standards. Batch-wise manufacturing variation was also reported. Thus, formulation of national policies and their proper implementation is necessary for manufacturing safe paints in Sri Lanka.