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Serra-Negra J, Paiva SM, Oliveira M, Ferreira E, Freire-Maia F, Pordeus I.Serra-Negra J, et al.Int J Environ Res Public Health. 2012 Jan;9(1):44-54. doi: 10.3390/ijerph9010044. Epub 2011 Dec 29.Int J Environ Res Public Health. 2012.PMID: 22470277Free PMC article.