What risks are associated with secondhand smoke for nonsmokers?

Secondhand smoke, also known as environmental tobacco smoke (ETS), has been declared by the U.S. Environmental Protection Agency as a "Class A carcinogen" - meaning that it is a major cause of cancer and other serious public health problems. The health of nonsmokers is adversely affected by secondhand smoke as seen in more than 3,000 cases of lung cancer and 40,000 heart attack deaths of nonsmokers each year who have been exposed regularly to ETS. Babies and young children, however, suffer the greatest risk from exposure to the toxic chemicals in smoke. Between 150,000 and 300,000 children who have been exposed to tobacco smoke in the environment are diagnosed each year with lower respiratory tract infections, such as pneumonia and bronchitis. These same children also suffer from a higher number of middle-ear infections, asthma attacks, and chronic coughing and wheezing. More recent studies have linked Sudden Infant Death Syndrome (SIDS) or "crib death" to infants whose mothers smoked during pregnancy or around them after birth.