Aug 22, 2016 09:30 UTC

Welcome to the 31st weekly episode of the series We Only Have One Planet to Live On. In this episode, we study noise pollution, which poses a threat against the environment.

In previous weeks, we spoke of water, air, and soil pollution and their impacts on the environment. One of the other pollutions that leave negative impacts on humans, plants, animals, and even inanimate objects is noise pollution.

Scientists opine that as the result of oscillation of air molecules and continuous changes in air pressure, sound is created. The sound waves spread in air longitudinally and can be perceived by mankind in a specific range of frequencies. Hence, sound waves are a form of mechanical waves which spread longitudinally and are heard upon reaching one’s ears. These waves can be spread in air in the form of different frequencies. However, the perceivable range of frequencies for mankind is between 20, and 20,000 Hertz. 

However, noise pollutions are unwanted sounds which sabotage our calm and/or individuals’ concentration at work. Hence, if music is performed at an inappropriate location and time, it is considered as a source of noise pollution. Sound is measured based on decibels and changes in air pressure and its value varies between zero decibel, which is the hearing threshold and 130 decibels which is the deafening threshold. Noise pollution is directly linked to industrial technology. In other words, concurrent with the growth of technology, the problem of noise pollution has taken new dimensions and has stirred more problems and concerns.

The sources of noise pollution are diverse. However, they mainly include traffic jams, air traffic, trains, industries, and constructions. In cities, specific sites, such as airports and train stations, car horns, auto’s exhaust pipes, and siren of ambulances, construction sites, and industrial machineries are the most important sources of noise pollution, while outside cities; roads and railways are the main sources of noise pollution. According to experts, presence of railways in a region can leave destructive impacts on that region’s plants and animals, because these railways pass through unique natural ecosystems and the noise pollution resulting from the passage of trains can leave an impact on those regions’ animals and plants and endanger the safety and security of the creatures and humans, who live next to these railroads, forcing rare creatures to migrate to other ecosystems; which in turn lays the ground for extinction of rare animal species.

Currently, noise pollution is considered as one of the most important environmental concerns in the majority of industrial states. A study shows that noise pollution causes several physical and mental ailments and imposes hefty costs on different communities. One of the most important impacts of noise pollution for mankind is a fall in hearing ability. Headache, dizziness, indigestion, constipation, stomach and intestine ulcers; itchiness, skin allergies; nervousness; high blood pressure, heart attack, and insomnia are the other negative impacts of noise pollution on mankind. Noise pollution boosts the secretion of adrenaline and cortisol hormones in blood. A rise in adrenaline leads to heart race, and a rise in cortisol mounts stress and anxiety in the individual. In the midst of noise pollution; blood pressure rises especially in skull, the volume of saliva falls, and mouth dries up. Noise pollution can also lead to miscarriage. Noise pollution is a stressor for mothers, while contracting womb veins, which provide food and oxygen for the fetus; thereby lowering the weight of newborns.

Noise pollution also poses a threat against animals. Laboratory studies have proven that sound waves beyond 85 decibels lower the hearing ability of animals. Even if noise pollution would not leave a significant negative impact on the hearing ability of animals; it can leave physical impacts on them such as a heart race and nervous reactions. Change of behavioral patterns such as a fall in reproduction and forgetfulness about the location of habitats are some of the negative impacts of noise pollution on animals. Meanwhile, studies on caged monkeys showed that their blood pressure rose by 30% upon exposure to noise pollution measuring at 85 decibels for a period of eight months.

A number of experiments which were carried out on mice showed noise pollution is a stressor factor in them, exposing mice to a wide range of ailments.

Untimely migration of wild animals and birds; miscarriage; ear bleeding; lack of appetite; aggressiveness; and shortage of lifespan are some of the other impacts of noise pollution on animals. Also, a body of studies proves that urban noise pollution lowers the population of birds and changes their behavioral patterns. Noise pollution also causes problems for bats in finding baits, and makes it difficult for frogs to find their mates. However, animals are not the only ones who face the consequences of noise pollution.

Many imagine that noise pollution leaves no negative impact on trees and plants; given that these living creatures have no ears or hearing ability like animals and human beings. However, new studies have revealed that noise pollution leaves countless impacts on trees. Animals can easily leave noisy and crowded habitats. Meanwhile, the trees of those regions experience lesser rate of pollination due to the declining population of animals, which leaves destructive impacts on trees. A precise and closer look at trees clearly shows the impacts of the noise pollution. For instance, the number of pine trees, which have been the habitats of many birds and animals, has declined due to noise pollution.

This comes while according to experts, trees can significantly contribute to reduction of noise pollution. They significantly decrease sound waves like a shield, with their leaves. Plants and trees can reduce noise pollution across highways if they maintain sufficient height, width, and density.

Meanwhile, noise pollution is one of the forgotten aspects of pollution of environment, and due to the limited knowledge of mankind about noise pollution, serious measures are yet to be taken against it. Nonetheless, scientists have concluded that noise pollution poses a major threat against the environment and bio diversity; and the international community should take measures against this type of pollution.