Don't Underestimate Effects of Noise Pollution

By Dr. Magdy Badran .. Consultant Ped Immunology

CAIRO, Nov. 23 (SEE) - Until now, noise has been the Cinderella form of pollution and people haven’t been aware that it has an impact on their health.

The World Health Organization estimates that 1.1 billion young people worldwide could be at risk of hearing loss due to unsafe listening practices. Nearly half of all teenagers and young adults are exposed to unsafe levels of sound from the use of personal audio devices.

Noise is one of the most common occupational health hazards. In heavy industrial and manufacturing environments, as well as in farms, cafeterias, the permanent hearing loss is the main health concern. Noise is thought to affect health by creating a state of constant stress. Production of stress hormones may cause long-term changes in the body that may be life-threatening.

Certain people may be more susceptible to noise-induced hearing loss than others. Genetic predisposition, age, chronic conditions such as diabetes and hypertension, and exposure to cigarette smoke can increase the risk of acquiring noise-induced hearing loss.

Noise-induced hearing loss among children is a serious public concern. Some studies on noise exposure in children have found increases in blood pressure, stress, annoyance, hyperactivity, behavior difficulties, and impaired sleep. Traffic noise at school affects children’s cognition, particularly memory and reading. Noise harms our children’s hearing, language acquisition, learning skills, and social interactions.

Traffic noise stresses and disturbs sleep. It has been associated with various diseases and has recently also been associated with lifestyle. Traffic noise alone may account for 3% of deaths from heart attacks and strokes, Given that seven million people around the world die each year from heart disease, the global death toll from traffic noise could be around 210,000.

Workplace chemicals that can pose a risk to hearing include organic solvents as toluene and ethylbenzene, heavy metals as mercury and lead. Asphyxiants as carbon monoxide, hydrogen cyanide and pesticides increase the chance of hearing loss.

Many women work in noisy jobs, especially women who work with machines, loud music, crowds of people, sirens, trucks, or airplanes. It was previously assumed that fetuses were well insulated from external noise, several studies have shown that noise, especially low-frequency noise, is physically conducted to the fetus.

The noise stimulates the inner ear through a soft tissue conduction route and could potentially affect the hearing of the fetus by damaging inner and outer hair cells within the cochlea, especially since the maturing cochlea is more sensitive to ototraumatic factors than the adult one.

The loud noise can alarm the fetus resulting in some unusual activity inside the womb. Prolonged exposure to sounds exceeding 90 to 100 decibels may elevate the unborn baby’s risk of hearing loss. It increases the chances of a premature delivery and giving birth to a low-birth-weight baby.

Loud noise is harmful to the inner ear (cochlea), it can damage cells and membranes in the cochlea. Listening to loud noise for a long time can overwork hair cells in the ear, which can cause these cells to die. Cigarette smoking may potentiate the harmful effects of noise on hearing and disturb the recovery mechanism in the cochlea.

Since noise-induced hearing loss is irreversible, prevention is the most effective strategy. Prevention tips include regular hearing check-ups personal hearing protection such as ear muffs or plugs, noise-canceling earphones or headphones can be used, limiting the time spent engaged in noisy activities and moving away from loud sounds.

Children and adolescents must be educated about the possible dangers of exposure to loud sounds from the misuse of personal audio devices and encouraged to develop safe listening habits. Noise exposure and noise levels should be reduced to acceptable levels. Pregnant women should not be exposed to loud noise.