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Alexopoulos EC, Geitona M.Alexopoulos EC, et al.Int J Environ Res Public Health. 2009 Sep;6(9):2456-69. doi: 10.3390/ijerph6092456. Epub 2009 Sep 15.Int J Environ Res Public Health. 2009.PMID: 19826556Free PMC article.