Continuous exposure to passive smoking leads to decreased sensitivity to cough reflex in children and resultant reduction of their immunity to many environmental threats, according to a new study.
The cough reflex is one of the important defense mechanisms of the body. Usually, the lungs and the lower respiratory passages are germ-free. If dust or dirt enters the lungs, they could become a breeding ground for bacteria and cause pneumonia or infection in the breathing tubes. When one coughs a blast of air comes out at high speed, scrubbing and clearing the airway of dust, dirt or excessive secretions.
Julie Mennella and Paul Wise from Monell initiated to investigate the mechanism that play a major role in making children of smokers at a higher risk of many respiratory illness like pneumonia and bronchitis.
"Cough protects our lungs from potentially damaging environmental threats, such as chemicals and dust. Living with a parent who smokes weakens this reflex, one of the most vital of the human body," Dr. Julie Mennella, a developmental biologist, said in a statement.
Nearly 60 percent of children aged between three and 11 and 18 million adolescents in U.S. are victims of passive smoking.
The study included 38 healthy children, aged between 10 and 17. Participants inhaled capsaicin, a burning element in chilli peppers, and a chemical stimulus for cough. Of the total participants, 17 were exposed to smoke at home through a nebulizer.
The dosage of the chemical was increased after each inhalation. At the end of the study, the investigators found continuous exposure to the chemical making children less sensitive. According to the investigators, this finding explains the mechanism behind some children developing respiratory illness and influencing teenagers to start the smoking habit at a younger age.
"This study suggests that even if an exposed child is not coughing, his or her respiratory health may still be affected by secondhand smoke," Wise said.
Earlier this year, in May, a study published in the Archives of Pediatrics & Adolescent Medicine found children being exposed to passive smoking even though their parents didn't actively smoke. According to the investigators, children are at a higher risk of the smoke present in the environment and recommended conducting blood tests to measure the level of cotinine (the chemical found in the body after being exposed to nicotine) in the body.
Breathing smoke-filled air can bring in many health problems, including cancer, according to National Service choices (NHS). Secondhand smoke contains more than 4,000 toxic chemicals and causes SIDS, asthma, meningitis, cough and cold and middle ear diseases in children.
