High levels of lead in adults may not be as harmful as people thought earlier, according to a study conducted by Pal Osterberg and colleagues at the university hospitals of Lund and Malmo, Sweden. Previous studies had suggested that adults who have high levels of lead in their body have poor concentration and failing memory. The researchers did not find any symptom of lead toxicity in workers who had worked at a smelting plant for about 10 years. However, some experts say that the researchers did not use the most sensitive tests to measure lead toxicity and the results could be flawed ( New Scientist , Vol 155, No 2092).