The Effects Of Noise Pollution

            Noise is becoming a severe disturbance to the human environment, and is deteriorating at a very fast rate, such that it is beginning to threaten human existence.  Sometimes, following a loud noise, we temporarily tend to get deafened, and it may take a while for hearing to return.  This transient loss of hearing is known as ‘temporary threshold shift’, and it often places the individual at a risk of developing permanent hearing loss.  The minute hair cells and present in the organ of Corti are very sensitive to harsh noises and get destroyed easily.  These delicate hair cells transmit electrochemical signals that are pricked up by the nerves in the inner ear and transmitted to the brain. Prolonged exposure to these harsh noises destroys the organ of Corti itself and results in permanent deafness (Bugliarello, et al., 1976).  Children may not learn to speak properly if they develop hearing loss.  Hence, parents should protect the child’s hearing so that other functions do not get affected (Bugliarello, et al., 1976).

            Hearing loss is beginning to affect the population, but it is seldom taken seriosuly.  Observations demonstrate that some humans are unable to hear high frequency sounds in the range of 20 Hz, although sounds in this frequency were classified as audible (Fletcher et al, 1953).  Hearing loss is of two types, namely, conductive and sensorineural.  In the conductive type, due to rupture of the eardrum or abnormalities in the ossicles of the middle ear (tiny bones which amplify the sound ways), the sound waves do not arrive at the cochlea.  Several hearing devices are available to counteract this type of hearing loss (Bugliarello, et al., 1976).  Sensorineural hearing loss worsens along with aging, but loud noises also play an important role.  The organ of Corti (that converts mechanical energy into electrical energy and transmits it to the brain) present in the inner ear is affected.  It is the most common type of hearing loss in the US.  Teenagers who are in a habit of listening to rock music played at loud volume for a long period of time are at a risk of developing this type of hearing loss (Bugliarello, et al., 1976).  Sensorineural deafness tends to be affected with prolonged exposure to higher noise levels, and is experienced as gradual hearing loss.  Specialized miniature devices implanted into the auditory canal can help to overcome this type of hearing loss (Nunez, D.G. et al, 1998).

            Noise disturbances can also affect sleep patterns and mental health.  Studies conducted previously demonstrated a clear relation between noise sensitivity, noise annoyance, sleep-disturbance and certain psychological symptoms; with exposure to noise pollution (both at the work-place and at home).  Community surveys conducted demonstrated that the effects of noise pollution often lead to impairment in the health status.  A study conducted demonstrated that exposure to higher noise levels during the night resulted in being awakened and sleeplessness for varying periods of time.  Another study was conducted to determine the noise exposure level at which annoyance would set in a human subject (along with physical changes like blood pressure).  Sounds above 80db lead to a change in the blood pressure.  However, some noises tend to be tolerated more easily than others (Smith, A. et al, 2002).

            Teenagers often prefer to use personal tape players, and this has also been associated with hearing loss.  However, the radio industry disagrees to this and instead says that hearing loss mainly arises due to improper use (hearing music for long periods at high volume).  The radio industry has been in place for a long time, but the problem regarding hearing loss has been observed only recently.  This is because people tend to use personal players in noise-polluted areas, and in an effort to counteract those noises, they increase the radio volume (Benarde, 1989).

            Noise pollution produced by aircrafts seems to cause some of the highest disturbance to sleep compared to any other sounds.  People living near airports more frequently are awakened by the aircraft noise, compared to any other sound.  The introduction of Boeings and jet aircrafts has really led to an increase in the noise levels.  Aircraft take-off and landings can especially very traumatic to the hearing.  Soon, supersonic and jumbo jets are to be introduced, and no one knows what the pollution levels are going to be like.  The aircraft industry is having several problems with the population.  Due to the increase in the population, residential areas often move in the direction of airports.  Besides, there has been a sudden rise in the demand for air travel, such that the pollution levels may be especially high during peak-flying hours.  Aircraft noise pollution can be associated with several symptoms such as rise in blood pressure, heart disorders, reading irritation, annoyance, and mental disturbances, in the residents who stay near airports.  Another study conducted by Jenkins et al., 1979, showed that mental illnesses were higher for people staying near airports, seemingly because of noise pollution (Nunez, D.G. et al, 1998).

            It may be seen that noise pollution is very hazardous to the health of the population.  People living and working in cities (especially near noisy prone areas, industries, traffic and airports) are at a risk of developing hearing loss and other health problems.  Some counties may have taken measure to control noise levels, but still the noise levels continue to remain high.

References:

Andrew Smith, Sheila Hayward, Susan Heatherley, David Nutt, Susan Wilson, Neil Rich “Noise and insomnia.” The Department of Health. 2002. NHS – UK. 15 Jan. 2007. http://www.dh.gov.uk/PolicyAndGuidance/HealthAndSocialCareTopics/NoisePollution/NoisePollutionGeneralInformation/NoisePollutionGeneralArticle/fs/en?CONTENT_ID=4031971&chk=ChjYP6

Bridget Shield and Julie Dockrell. “The effects of noise on the attainments and cognitive performance of primary school children.” The Department of Health. 2002. NHS – UK. 15 Jan. 2007. http://www.dh.gov.uk/PolicyAndGuidance/HealthAndSocialCareTopics/NoisePollution/NoisePollutionGeneralInformation/NoisePollutionGeneralArticle/fs/en?CONTENT_ID=4031962&chk=9Pe4Jx

Daniel G. Nunez. “Cause and Effects of Noise Pollution.” Interdisciplinary Minor in Global Sustainability, University of California, Irvine. 1998. UC Irvine School of Biological Sciences. 15 Jan. 2007. http://www.dbc.uci.edu/~sustain/global/sensem/S98/Nunez/Noise.html