Secondhand smoke is accountable for 42,000 deaths annually to nonsmokers in the United States, including nearly 900 infants, according to a study.
Altogether, annual deaths from secondhand smoke represent nearly 600,000 years of potential life lost — an average of 14.2 years per deceased person — and $6.6 billion in lost productivity, amounting to $158,000 per death, reported researchers with the University of California, San Francisco.
The study, which the researchers said involved the first use of a biomarker to gauge the physical and economic effects of cigarette smoke, revealed that secondhand smoke exposure disproportionately affects African Americans, especially infants.
More broadly, despite public health efforts to reduce tobacco use, secondhand smoke continues to take a substantial toll on nonsmokers.
“In general, fewer people are smoking and many have made lifestyle changes, but our research shows that the impacts of secondhand smoke are nonetheless very large,” Wendy Max, PhD, the studys lead author and a professor of health economics at the UCSF School of Nursing, said in a news release.
“The availability of biomarker-measured exposure allows us to more accurately assess the impact of secondhand smoke exposure on health and productivity,” added Max, also co-director of the UCSF Institute for Health & Aging. “The impact is particularly great for communities of color.”
Exposure to secondhand smoke is linked to a number of fatal illnesses including heart and lung disease, as well as conditions affecting newborns such as low birth weight and respiratory distress syndrome.
About a decade ago, the Centers for Disease Control and Prevention — using data from the California Environmental Protection Agency — reported that 49,400 adults died annually as a result of secondhand smoke exposure. Additionally, the CDC reported that 776 infants annually died as a result of maternal exposure in utero.
Those widely-cited statistics relied on self-reporting to gauge the impact of secondhand smoke. The new study shows that the statistics on fatalities resulting from ischemic heart disease are 25% lower than previously reported (34,000 deaths compared with 46,000), but statistics are nearly twice as high for lung cancer deaths (7,333 deaths compared with 3,400). The new study also shows higher infant mortality (863 deaths compared to 776).
The researchers used serum cotinine, a biomarker that detects the chemical consequences of exposure to tobacco smoke in the bloodstream, to measure exposure to secondhand smoke. That measurement reflects secondhand exposure in all settings, not just home or work, the authors wrote.
The scientists gauged the economic implications — years of potential life lost and the value of lost productivity — on different racial and ethnic groups. Mortality was measured in two conditions for adults: lung cancer and ischemic heart disease; and four conditions for infants: sudden infant death syndrome, low birth weight, respiratory distress syndrome and other respiratory conditions of newborns.
Of the 42,000 people who died from secondhand smoke, 80% were white, 13% were black and 4% were Hispanic. The vast majority of deaths were caused by ischemic heart disease. Black babies accounted for what the researchers called a startlingly high 24% to 36% of all infant deaths from secondhand smoke exposure even though blacks represented only 13% of the total U.S. population in 2006.
The value of lost productivity per death was highest among blacks ($238,000) and Hispanics ($193,000). The authors wrote that black adults had “significantly greater exposure rates than did whites in all age groups.” Black men ages 45 to 64 and 20 to 44 had the most secondhand smoke exposure. Black women ages 20 to 44 had a higher exposure rate (62.3%) than did any other women.
“Our study probably underestimates the true economic impact of secondhand smoke on mortality,” Max said. “The toll is substantial, with communities of color having the greatest losses. Interventions need to be designed to reduce the health and economic burden of smoking on smokers and nonsmokers alike, and on particularly vulnerable groups.”
The study appeared Sept. 20 on the website of the American Journal of Public Health. The study abstract is available at http://ajph.aphapublications.org/doi/abs/10.2105/AJPH.2012.300805.