Dr. Joseph Graziano, interim department chair of environmental health sciences at Columbia University's Mailman School of Public Health, said the public should switch away from lead bullets -- even if the research is still developing.

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"There have been a lot of studies that indicate that there are probably other mechanisms, " says the senior author of the New York City study, Robin Whyatt, DrPH, a professor of clinical environmental health sciences at Columbia University's Mailman School of Public Health.

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Elaine Larson, professor of epidemiology at Columbia University's Mailman School of Public Health.

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