Lead loadings in household dust in Delhi, India

Lead in household dust is dangerous to children who ingest lead from playing close to the ground, and having frequent hand-to-mouth contact. Although there have been several investigations of lead levels in India in air, blood and new paint, the literature is sparse on the levels of lead in household dust. This study analyzed 99 samples of dust taken from bare floors and 49 samples of dust taken from windowsills in a cross-section of Delhi, India houses for lead loadings. The arithmetic mean of lead loading for floor samples and windowsill dust samples was found to be 36.24 microg/ft(2) and 129.5 microg/ft(2), respectively. The geometric mean of dust lead loading for floor and interior windowsill samples was found to be 19.7 microg/ft(2) and 75.5 microg/ft(2), respectively. Comparing the results with US geometric mean dust lead levels from a national cross-section of US housing, which in 2000 were 1.1 microg/ft(2) and 9.4 microg/ft(2) on floors and windowsills, respectively as reported by Jacobs et al. (2002) suggests that the lead content of the dust in Delhi homes is much higher than that in the national data in the US and that the levels pose a hazard to children. Practical Implications The present study is first of its kind in this part of the world. In the context of ongoing efforts to eliminate lead from paints worldwide this research will help the scientists and policy makers in assessing the Children's exposure to lead in developing country as well. Since more than one half of the housing units tested had at least one dust lead sample exceeding US health-based standards, health care providers and public health officials need to give attention to possible lead poisoning in Delhi children. Routine blood lead screening of children should follow recommended public health practice for children at risk. Additional larger-scale studies are needed in Delhi and elsewhere to determine how representative these findings are and to attempt to delineate the sources of the high dust lead which are expected to vary depending on the location. Knowledge of the sources is needed to appropriately allocate resources. From other studies performed in India it is likely that lead-based paint is one of the sources and its continued use should be discontinued.