Noise Pollution and impact on Environment

We live in a noisy world, and much of that noise is made by humans. Traffic, machinery, electronics—it’s a constant barrage of sound. For many of us, the concept of pollution is limited to nature and resources. However, the noise that tends to disrupt the natural rhythm of life makes for one of the biggest pollutants. According to the National Park Service (NPS) in the United States, noise pollution has an enormous environmental impact and does serious damage to wildlife. Experts say noise pollution can interfere with breeding cycles and rearing and is even hastening the extinction of some species. How does our noise affect the animals around us? Unlike us, they can’t put in some earplugs, close a window or turn off the stereo. Recent studies are showing that our increasingly loud world is having negative effects on a range of animals, across a variety of habitats. ‘Wait!’ we hear many say, ‘Natural landscapes aren’t always quiet either.’ That’s true, nature can be noisy—from bird calls to wild winds, thunder, animal migrations and constant zooming sound of ocean waves and waterfalls, the natural environment creates and uses noise in a complex information network. Most animals, however, have specially adapted to the natural noises in their environment—they are aware of them, understand them and know how to use and interpret them. So do the human beings living in their vicinity. However, when we begin to add artificial, unfamiliar noises to natural sounds capes, it can alter the acoustic environment of these marine and terrestrial habitats. This can cause a range of problems. It can affect an animal’s ability to hear or make it difficult for it to find food, locate mates and avoid predators. It can also impair its ability to navigate, communicate, reproduce and participate in normal behaviors. Interest in the way sound affects wildlife has intensified over the last decade as more and more studies begin to explore how these changes in behaviour could have flow-on effects for not only individual animals and their populations, but for whole ecosystems. It is not the nature’s noise, but, the man-made noise that is of extreme concern today.

What is ‘noise pollution’? Noise pollution is generally defined as regular exposure to elevated sound levels that may lead to adverse effects in humans or other living organisms like animals, birds and insects. According to the World Health Organization, sound levels less than 70 dB are not damaging to living organisms, regardless of how long or consistent the exposure is. Exposure for more than 8 hours to constant noise beyond 85 dB may be hazardous. If you work for 8 hours daily in close proximity to a busy road or highway, you are very likely exposed to traffic noise pollution around 85dB. This type of pollution is purely man-made and so omnipresent in today’s society that we often fail to even notice it anymore. Even before taking a closer look at the various causes of noise pollution, let us first understand the two primary types of noise.

Man-Made Noise: This refers to the noise created due to man-made activities. It can be anything from construction work, noise from the air, vehicular traffic, household noise, noise from pubs and bars, to name a few. Ranging from 30 to a whopping 140 dB, this form of noise is extremely harmful to humans. These can be:

• Street-traffic sounds from cars, buses, pedestrians, ambulances etc.
• construction sounds like drilling or other heavy machinery in operation
• airports, with constant elevated sounds from air traffic, i.e. planes taking off or landing
• workplace sounds, often common in open-space offices
• constant loud music in or near commercial venues
• industrial sounds like fans, generators, compressor, mills
• train stations traffic
• household sounds, from the television set to music playing on the stereo or computer, vacuum cleaners, fans and coolers, washing machines, dishwashers, lawnmowers etc.
• events involving fireworks, firecrackers, loudspeakers etc.
• armed conflicts generate noise pollution through explosions, gunfire etc. The dysfunctions, in this case, are likely caused by the conflict and insecurity and less by the noise pollution in itself, although that compounds stress levels too.

Environmental Noise: Environmental Noise refers to the kind of noise occurring from a range of environmental activities. This can be anything from the mating call of animals to the sound of thunderstorms that often go up to 140 dB.

However, as mentioned earlier, it is the man-made noise that is of extreme concern today and needs to be controlled or curbed to an eco-friendly level so that all of us including the other species residing on Earth can live harmoniously without interfering with each others’ behavioural pattern.

 

Human Diseases Caused by Noise Pollution

Today, whether we realize we are subjected to it or not, noise pollution can be hazardous to our health in various ways, like:

• Hypertension is, in this case, a direct result of noise pollution caused elevated blood levels for a longer period of time.
• Hearing loss can be directly caused by noise pollution, whether listening to loud music in your headphones or being exposed to loud drilling noises at work, heavy air or land traffic or separate incidents in which noise levels reach dangerous intervals, such as around140 dB for adult or 120 dB for children.
• Sleep disturbances are usually caused by constant air or land traffic at night, and they are a serious condition in that they can affect everyday performance and lead to serious diseases.
• Child development. Children appear to be more sensitive to noise pollution, and a number of noise-pollution-related diseases and dysfunctions are known to affect children, from hearing impairment to psychological and physical effects. Also, children who regularly use music players at high volumes are at risk of developing hearing dysfunctions.
• Various cardiovascular dysfunctions. Elevated blood pressure caused by noise pollution, especially during the night, can lead to various cardiovascular diseases.
• Dementia isn’t necessarily caused by noise pollution, but its onset can be favored or compounded by noise pollution.
• Psychological dysfunctions and noise annoyance. Noise annoyance is, in fact, a recognized name for an emotional reaction that can have an immediate impact.

 Effects of Noise Pollution on Wildlife and Marine Life

We might think at least our marine creatures are okay! They swim in the quiet depths of the ocean with only the gentle lapping of waves to listen to. But, unfortunately, noise made by humans is increasingly disrupting life below the surface, with many marine animals being affected. Our oceans are no longer quiet. As per Dr Sylvia Earle, oceanographer, undersea noise pollution is like the death of a thousand cuts. Thousands of oil drills, sonar, seismic survey devices, coastal recreational watercraft and shipping vessels are now populating our waters, and that is a serious cause of noise pollution for marine life. Rising levels of intense underwater sound are produced by a range of sources—shipping traffic, industrial noise from oil and gas exploration, seismic surveys, military sonar and others. This cacophony can present a range of problems for marine species, many of which rely on hearing as their primary sense for mating, hunting and communicating. Whales are among the most affected, as their hearing helps them orient themselves, feed and communicate. Noise pollution thus interferes with cetaceans’ (whales and dolphins) feeding habits, reproductive patterns and migration routes, and can even cause hemorrhage and death. Each sound in itself may not be a matter of critical concern, but taken all together, the noise from shipping, seismic surveys, and military activity is creating a totally different environment than existed even 50 years ago. That high level of noise is bound to have a hard, sweeping impact on life in the sea. Whales, dolphins and porpoises (a small toothed whale with a low triangular dorsal fin and a blunt rounded snout) rely heavily on sound, and so are disrupted by our noise in the ocean. It’s not only the larger animals that are being affected. Squid and other cephalopods have also shown negative responses to noise pollution. Even short exposure to low-frequency, low-intensity sounds―such as those produced by offshore oil drilling and commercial fishing can disturb the balance systems of squid, octopuses and cuttlefish. 

Other than marine life, land animals and birds are also affected by noise pollution in the form of traffic, firecrackers etc. especially, the birds are especially affected by the increased air traffic. The researchers have concluded that ‘road noise can alter key survival behaviours’ and that ‘these findings highlight that the presence of animals in a location is no guarantee of population and ecological integrity’. So while noise pollution may not necessarily drive animals away from a site, it may alter their established behaviours and be having a less-obvious negative effect on their physical wellbeing. Many species of birds and animals rely on sound for communicating with each other and increased level of noise pollution can have detrimental effect on their behavioural communication pattern. Interestingly, noise pollution can also kill off your sex life—at least if you’re a frog. A study conducted in Melbourne, Australia, by Dr Kirsten Parris and colleagues found that, for some highly vocal frog species, noise pollution is correlated with an increase in the frequency of their calls. This increase partially compensates for the loss of communication distance in noise-traffic areas experienced by these frogs. The mating call of male pobblebonk frogs could historically be heard up to 800 metres away by interested females. At very noisy sites, this is reduced to just 14 metres. If male frogs alter their call to a higher frequency to be heard, the females may not like what they hear. Female frogs of some species prefer lower-pitched calls, which often indicate larger and/or more experienced males. Once again for the male frogs, it’s a tough call—to not be heard, or to be heard and rejected!

 

The body of evidence regarding the harmful effects of noise pollution on a range of animals—from the giant blue whale to the pobblebonk frog—is growing. But what can we do about it? We won’t suddenly all stop driving, close our industries or cease shipping and ocean exploration. Solutions will need to come from all sectors. Science can help us better understand the issues and problems these species are facing; technical innovation will need to provide improved, quieter technologies; governments will need to be active in passing legislation limiting or restricting periods and types of noise; and the rest of us can take small steps to mitigate our own noise output. After all, the problematic noise is being generated by the human world, and it is up to us to find ways to reduce and stop it. Managing our natural environment is about managing people; we need to act.