Addressing noise pollution on this World Hearing Day 2023

Key highlights:

Globally, one in five people live with hearing loss.
It is projected that by 2050 one in four people are likely to suffer from hearing related problems. Approximately, 700 million people will likely to suffer from moderate to high hearing loss globally.
80% of people with hearing loss live in low and middle income countries.
Global cost of addressing hearing problems is US $ 980 billion annually.
In South East Region, people living with hearing problems rose to 401 million in 2021.
In India, 63 million people suffer from significant auditory loss in India.

Abstract: Noise pollution receives far less attention than water or air pollution, writes, The Lancet. According the World Health Organization (WHO), one million Disability adjusted life years (DALYs) are lost annually due to traffic noise. Moradabad a city in Uttar Pradesh is said to be one of the most noise polluted city globally, Frontiers reports. Hearing problems not only affect one's health but one's productivity, education and mental health and well-being. Early identification is the first step in addressing the issue. Calling it is as the 'invisible disability' it remains undetected. People generally don't pay enough attention to the slow process of hearing loss. It is important to note that access to hearing care services data is poorly documented in many countries which lack of literature around it. From advocacy programs, to diagnoses and treatment should be further streamlined.

Hearing aids as an important management strategy to treat people with hearing problems is very effective. However, factors such as cost, stigma and perceived hearing disability are the reasons for non-use of hearing aids by many individuals.

Accessibility of hearing aids and cochlear implants is of great concern. It is studied that only 17% of population those who would benefit from using a hearing aid use them. Globally, 400 million people would benefit from using hearing aids, yet less than 68 million (17%) people actually use them. Total coverage gap is over 83% highest in African regions and lowest in WHO European regions. However, the number is highest in South-East Asia region.

Image 1 Number and percentage of those who need hearing aids but are not using one

Image 2: projected figures of prevalence of hearing loss (all kinds and grade) in WHO regions (2019-2050), WHO report on World Report on Hearing, 2021

In India, 63 million people suffer from auditory loss. Every year, one lac babies are born with hearing impairment in India. Hearing disability is higher in children (0-4 years) than in other age groups.

In 2006, The Indian Government launched the National Programme for Prevention and Control of Deafness (NPPCD) for controlling problems related to hearing impairments, their screening and diagnosis both at institution levels and community levels. This program comes under National Health Mission in the category of Non Communicable Disease Control Programs. However, this program has no specific targets for noise induced hearing loss (NIHL). In India, more than 50 million workers work in industries with very high sound levels, according to a recent review article. This exposure to high sound levels can cause hearing problems in the long run. Further, there is no strong provision for noise control under The factory act of India. In India, continuous noise exposure of 90 dB for 8 hours is the maximum limit recommended by the Directorate General of Factories Advisory Services and Labor Institutes. But this enforcement limit is questionable in many areas and services.

Availability of ENT specialists

When we say the prevention and care of hearing related problems are important, the suffix is dominated by the presence of availability of efficient health care manpower. Below image highlights the strong gap in the availability of ENT (Ear, nose and throat) specialists in WHO regions (138 countries):

Image 3: density of ENT specialists among WHO regions

Major problems lies with African region, where approximately 56% of countries have less than one ENT specialist per 1 million population. On the other hand, 67% of European countries has more than 50 specialists. Classified based on the income groups, 78% of the lower income countries has less than one specialist. Audiologists also play an important role in addressing hearing loss through hearing technology. Again the manpower is minimal in African countries (less than 1 audiologist per 1 million population).

The Report cited an example of a study conducted in Delhi showed that 1075 ENT specialists (in contrast to current 650 specialists) would be needed to identity and diagnose common hearing problems in patients of age 0-15 years.

Noise pollution in cities

According to the latest report by United Nations Environment Programme (UNEP), Frontiers 2022 documented the increase in noise pollution in cities and its impact on human health and well-being. (Frontiers_2022.pdf) Out of 13 polluted cities in South Asia, 5 belongs to India which recorded alarming levels of noise pollution namely: Kolkata (89 dB), Asansol (89 dB), Jaipur (84 dB), Delhi (83 dB) and Moradabad (114 dB). In India, noise limits for vehicles applicable at manufacturing stage (applicable) from the year 2005 ranges from 74-80 dB. Report_681-2018.pdf (cpcb.nic.in) These number is higher than what the WHO recommended levels shows.

Noise pollution which is a major environmental issue these days. Noise coming from construction areas, traffic, roads, airports, industries, loud music, etc. specially from urban areas are of concern. Decibels (dB) are of units that measure loudness of sound. It is documented that listening to music at the maximum volume (90-100dB) can cause hearing damage after 15 minutes of play. Regular exposure to 80 dB for eight hours can cause permanent hearing damage. Below image shows the World Health Organization recommendations on noise levels:

Image 4: WHO recommendations on noise levels

Anthropogenic noise can reduce one's ability to reproduction and cause mortality and emigration. Even it prevents the body mechanism to lower down the night time blood pressure which is very important. Annually, 12,000 premature deaths are due to the prolonged exposure to noise pollution in Europe. Further, there are 48,000 cases of ischemic heart disease annually.

Research shows, continuous exposure to noise pollution pose as a risk factor for developing cardiovascular diseases and metabolic disorders like high blood pressure, arterial hypertension, diabetes and coronary heart disease. Frontiers_2022.pdf

Conclusion

World Hearing Forum (WHF) established in 2018 by the World Health Organization has created a global advocacy alliance inviting its member countries & its stakeholders ( hearing care) to join hands and fighting off this disability. One very interesting program started in London in 2019 to build Ultra Low Emission Zone encompassing 3.8 million people. The main idea was to improve the air quality by encouraging electric vehicles, however it also resulted in bringing down the noise pollution in that zone. As the World Hearing Day 2023 is approaching near (3rd March), let us contemplate on the theme, "Ear and hearing care for all! Let's make it a reality and build a more strong primary care system.

References: