Noise Pollution: Environmental Impact and What You Can Do

Have you ever been somewhere truly free from the sounds of humankind? We become immune to the sounds of distant traffic and especially the subtle hum of planes above, but there are few places that don't have some form of noise pollution.

Noise pollution is noise that has surpassed ambient noise levels and has a harmful impact on humans and animals. This type of pollution is generated by humans and is a form of environmental degradation. It can serve as a source of stress on fauna, can have negative effects on animal welfare, and can even cause behavioral changes in birds, according to a study on the impacts of noise pollution on birds. 

Noise pollution can be problematic when frequencies that are produced disrupt information transmission in animals, specifically animals that use similar frequencies to communicate. These disturbances can also lead to higher anti-predator behaviors in situations that don’t require it, as well as change species vocalization, increase stress and stress-related diseases, and have the potential to decrease populations.

What is Noise Pollution?

Noise pollution can also be defined as an unwanted sound. The noise that is studied usually refers to occupational noise instead of social noise or environmental noise like construction.

In the E.U., around 56 million who live in areas with a population size of more than 250,000 people are exposed to more than average traffic noise. In the United States, noise has been shown to be increasing in California due to street traffic and increased at a rate of 6.7 dBA (A-weighted decibels). 

Noise pollution's impact on the environment can be classified as:

• Chronic Contamination / Continuous Noise: Constant exposure to noise; this type of pollution can lead to hearing impairment.
• Temporary Contamination with Physiological Damage: Exposure to a limited source of noise; an example is exposure to explosives.
• Temporary Pollution Without Damage: Continuous noise for a limited period of time, like street noise—this can lead to temporary hearing impairments.

Meanwhile, low-frequency noise is described as the background noise that comes from urban environments like air conditioning systems or vehicles. Traffic accounts for 80% of the environmental impact of noise. In animals, traffic noise can reduce foraging efficiency, and in birds can affect their reproductive system.

Examples of Noise Pollution

Barcelona, Spain

Barcelona is among the top cities exposed to noise pollution. Almost 48% of city blocks had an average noise level over 65dB, and only 5% of city blocks had noise levels under 55dB, according to research on environmental noise inequities in the city. The area with the highest noise level was the Eixample district; this district has high flows of street traffic and is also where the very popular La Sagrada Familia is located. This district, as well as the Sarria-Sant Gervasi district, experience levels over 70dB. In Barcelona, 94% of the population lives in city blocks that experience high-noise levels. In Madrid, 80% of all urban noise comes from road traffic, according to an impact assessment of traffic noise in Madrid. In general, the E.U. has shown that 65% of Europeans live in major urban areas that are exposed to high noise levels.

New York City, United States

Noise has been consistently reported as the number-one quality-of-life issue affecting residents in New York City. Sound pressure levels were reported at 70 to 85 dB in midtown Manhattan, which is above average and is at a level that poses health hazards, according to an assessment of noise pollution in NYC. More than two million people in New York City reported that they were disturbed from sleep by noise once a week; 78% of those people reported being disturbed three or more nights each week, according to a paper on the effects of ambient noise on sleep. Traffic noise caused 53% of sleep disturbances. Measured locations in New York City with noise levels greater than 70dB increased risk of hearing loss. These noise levels were especially high in areas with a lot of traffic, during the morning and evening commuting periods, and all around Manhattan, as reported in an assessment of street-level noise in New York City. The assessment also found that the highest noise measurement occurred when sirens, heavy pedestrian traffic, or construction was present. Street-level noises contribute to 4% of total noise exposed to the NYC public.

Noise Pollution and the Clean Air Act

The Clean Air Act Amendment added Title IV to the document, which relates to noise pollution. This amendment established the EPA Office of Noise Abatement and Control to study the effect of noise on public health and the effect on wildlife, the psychological and physiological effects it may have on people, and the effect of sporadic extreme noise. The sources of noise that are regulated by the EPA include construction equipment, trucks, transport equipment, low-noise emission products, and rail and motor carriers. It also regulates the labeling of hearing protection devices.  During the time this amendment was written, the EPA identified the average exposure to environmental noise to be 70 dB over 24 hours and average levels of 55 dB outdoors. However, the Office of Noise Abatement and Control was closed as the administration thought it was best if issues regarding noise were handled at the local and State level, according to the EPA.

The Noise Control Act of 1972 and the Quiet Communities Act essentially replaced the office and have yet to be rescinded, however the EPA’s website states they are “essentially unfunded.” Since the Clean Air Act and the previously mentioned amendment are no longer enforced, people can look at their state’s regulations. For example, Colorado limits the decibels produced by noise in residential, commercial, light industrial, and industrial zones between a set time. Their statute also considers periodic, intrusive, or shrill noises as a nuisance. The California Noise Control Act reiterates the harm excessive noise can have on physiological and psychological health, and also states that people in California are entitled to having a “peaceful and quiet” environment without noise that could be hazardous to their health.

Effects of Noise Pollution on Wildlife

The greatest effect of noise pollution on the environment is on animals. Noise pollution can affect an animal's ability to detect acoustic signals, affect courtship behaviors, cause birds to produce fewer eggs, and cause fewer offspring to reach reproductive age. On detecting acoustic signals, noise can also be produced in the same frequencies in which animals vocalize and can interrupt the transmission of information.

Noise affects many species of animals, from amphibians, arthropods, birds, and fish to mammals, mollusks, and reptiles.

According to the World Health Organization, noise is one of the most hazardous forms of pollution and has become omnipresent in aquatic and terrestrial ecosystems.

These disturbances can have long-term consequences. For example, some species may perform anti-predator behavior due to the confusion noise may create, as is the case with the impact of noise pollution on the saffron finch.

In this case, the noise created by traffic changed the behavior of saffron finches and made them less aggressive. In an environment with heavy noise, the male bird would display less aggressive behaviors when confronted by an intruding bird. This may be because they pay less attention to the intruder if unwanted noise masks the information that dictates the attributes of the intruder. The study predicts that if noise pollution were to continue, this species would continue to exhibit anti-predator behavior, as well as eat and reproduce less. This type of behavioral change was also found in the chipping sparrow.

What Can Be Done?

Trees can be used against noise pollution, according to an investigation on the effects of leaves, branches, and canopies on noise pollution. By decreasing the area in which noise is made and increasing tree presence with tree belts of at least 12 meters, trees could serve as a noise barrier in urban areas. Another study found that tree belts with a width of 30 meters could be planted on the roadside and have more than 6dB reduction of noise than a grassland would. The conclusion was that more trees, branches, and leaves could reduce noise pollution.

Regulations have also been placed in the U.S. statewide and local governments to reduce noise pollution. New York, for example, has a regulation that looks at occupational noise exposure; this ranges from monitoring noise to providing personal protective equipment. Many states and local governments in the U.S. have their own regulations regarding noise pollution; however, many focus on the human impacts that noise pollution has and not the environmental impacts.