This volume stems from the Second International Conference on Environmental Stressors in Biology and Medicine, which occurred October 5-7, 2011 in Siena, Italy. Included are short reviews and perspectives on the basic mechanisms of environmental stressors; physical and chemical stressors and related diseases; air pollutants and related diseases; protection afforded by food and pharmaceuticals; and food as a source of stressors. NOTE: Annals volumes are available for sale as individual books or as a journal. For information on institutional journal subscriptions, please visit www.blackwellpublishing.com/nyas. ACADEMY MEMBERS: Please contact the New York Academy of Sciences directly to place your order (www.nyas.org). Members of the New York Academy of Science receive full-text access to the Annals online and discounts on print volumes. Please visit http://www.nyas.org/MemberCenter/Join.aspx for more information about becoming a member.