The noise pollution people living near an airports are subjected to puts them at risk for serious health conditions — and they may not even know it, research shows.
"In the U.S., noise has been an overlooked environmental pollutant," Junenette Peters, an associate public health professor at Boston University, told The Brink, a university publication that highlights research, earlier this year. Peters helped lead a recent study that found people who are exposed regularly to even low levels of aircraft noise are more likely to self-report higher body mass indexes, an indicator of obesity. Obesity can lead to high blood pressure, stroke and other health complications.
"In our modern world, noise is continually around us and our bodies may not have adjusted to this constant input of noise," Peters said. "Noise influences stress responses, which may start a series of events that can lead to higher BMI and later to disease."
The latest research, published last month, shows the adverse impact aircraft noise has on sleep. Researchers at the University of Leicester in England found that even with a full-night's sleep, people exposed to high levels of aircraft noise, defined as 55 decibels or more, moved more during their sleep – a sign of sleep disruption. People exposed to higher aircraft noise levels also had disrupted sleep-wake cycles, indicating that their sleep was less regular compared to people exposed to 45 decibels or less.
A library typically has a noise level of 40 decibels; a conversation at home is about 50 decibels.
"The key message for the public is that higher night-time aircraft noise was linked with disturbed sleep quality, even if people didn't realize it," the study's lead author Xiangpu Gong said in a news release. "Sleep disturbance could have long-term effects on health, so it's important for policies to address and reduce noise pollution from airplanes."
Previous research has found that people living near airports are more likely to sleep less than seven hours a night. Chronic sleep disturbance from airplane noise can affect mood, memory and judgment. It also has been linked to a 36% increased risk of colorectal cancer, a 48% increased risk of heart disease and a nearly three-times higher risk for type 2 diabetes, according to Johns Hopkins Medicine. It also has been tied to a weakened immune system and higher blood pressure.
For the latest study, researchers examined data from more than 80,000 people living near London Heathrow and three other major airports. The study participants wore wearable devices while they slept so researchers could analyze data about their movements during sleep. They also answered surveys about their sleep quality, how long they slept and whether they napped during the day.
Philly International Airport has sought to reduce noise
There are several factors that impact the amount of aircraft noise heard on the ground, according to the Federal Aviation Association. They include the plane's model, engine, flight path and whether the plane is taking off or landing.
"Noise experienced on the ground also depends on flight schedules, which can vary depending on the time of day, season of the year, or other operational factors," the FAA says on its website. "Weather also plays a large role, since sound attenuates (dissipates) differently depending on weather conditions (wind speed and direction, temperature, etc.)."
That means homes near airports may experience varying levels of noise exposure over a day, week or year.
Philadelphia International Airport's noise monitoring system – an FAA requirement – measures noise levels in nine areas throughout the region at all times.
In 2012, the airport's Noise Office developed a program to educate pilots about flight routes that could reduce noise in residential areas. The program also instituted other policies, like one requiring engine tests after maintenance work to be approved ahead of time and not run longer than 20 minutes.
The airport also asks planes to fly down the middle of the Delaware River until they reach sufficient altitude to perform a turn between 10 p.m. and 6 a.m. Doing so reduces noise exposure to the nearby communities. Voluntary compliance in recent years was more than 99% each month, airport officials have said.
Despite increasing air traffic, the Noise Office reports that noise pollution has steadily decreased since 1980. People with concerns about aircraft noise near their homes can email the Noise Office. They are asked to include their name and address, the date and time of the flight, a description of the aircraft and its sound, and their contact information.
