Reference:23rd Annual Conference of the International Society for Environmental Epidemiology (ISEE) 2011, Barcelona, Spain, 13 Sep 2011 - 16 Sep 2011. Abstracts of the 23rd Annual Conference of the International Society of Environmental Epidemiology (ISEE). September 13 - 16, 2011, Barcelona, Spain. Environ Health Perspect :-. http://dx.doi.org/10.1289/ehp.isee2011. Sep 2011