A study performed by Dr. Marcus S. Cooke, professor in Florida International University’s Robert Stempel College of Public Health and Social Work’s Department of Environmental Health Sciences, along with visiting scholars Dr. Chiung-Wen Hu, Dr. Mu-Rong Chao and Dr. Yuan-Jhe Chang, from Chung Shan Medical University in Taiwan, found that children are particularly vulnerable to exposure to environmental tobacco smoke.
For the study, published in Environment International (Volume 120, November 2018, Pages 238-245), the researchers looked at various markers in urine, to examine the levels of exposure to environmental tobacco smoke in adults and children. While cotinine, a byproduct of nicotine that can be found in the body, has been widely studied as a biomarker of environmental tobacco smoke, Cooke and his team also looked at different metabolites to better understand the effects of second- and third-hand smoke.
These metabolites, unlike cotinine, can combine with a person’s DNA and produce adducts that are directly linked to an increased risk of lung cancer.
The results showed that the distribution of urinary cotinine concentrations in both adults and children were similar, whereas the children had much higher levels of the DNA damaging metabolites, compared to the adults. This indicates that while the exposure is the same, the effects are vastly different. This is because children are less able to metabolize the toxins and excrete them from their bodies.
As smoking in the presence of children has declined, their exposure to second-hand smoke has become less of an issue. However, what is increasingly clear is that a significant proportion of the chemical present in smoke adheres to clothing, skin and hair of smokers, as well as furnishing and dust in the environment, all of which represent third-hand smoke.
“This is another proof point that exposure to second- and third-hand smoke is dangerous, especially for more vulnerable populations like children,” said Dr. Cooke. “We need to continue to raise public awareness of the dangers of environmental tobacco smoke. Many still believe that by simply not smoking around children, they are protected; but this study proves otherwise.”
According to the Centers for Disease Control and Prevention, while cigarette smoking among U.S. adults has declined, 38 million Americans still smoke.