SACRAMENTO >> Mike Thomson’s friends refuse to stay over at his house anymore.

Thomson lives about 50 yards from a busy freeway that bisects California’s capital city, one that has been increasingly used as a speedway for high-speed races, diesel-spewing big rigs, revving motorcycles — and cars that have been illegally modified to make even more noise.

About the only time it quiets down is Saturday night between 3 and 4 a.m., Thomson said.

Otherwise, the din is nearly constant, and most nights, he’s jolted out of sleep five or six times.

“Cars come by and they don’t have mufflers,” said Thomson, 54, who remodels homes for a living. “It’s terrible. I don’t recommend it for anyone.”

Thomson is a victim of noise pollution, which health experts warn is a growing problem that is not confined to our ears, but causes stress-related conditions like anxiety, high blood pressure, and insomnia.

Legislating noise

California legislators passed two laws in 2022 aimed at quieting the environment. One directs the California Highway Patrol to test noise-detecting cameras, which may eventually issue automatic tickets for cars that make noise above a certain level. The other forces drivers of illegally modified cars to fix them before they can be re-registered.

“There’s an aspect of our society that likes to be loud and proud,” said state Sen. Anthony Portantino (D-Glendale), author of the noise camera law. “But that shouldn’t infringe on someone else’s health in a public space.”

Most states haven’t addressed the assault on our eardrums. Traffic is a major driver of noise pollution — which disproportionately affects disadvantaged communities — and it’s getting harder to escape the sounds of leaf blowers, construction, and other irritants.

California’s laws will take time and have limited effect, but noise control experts called them a good start. Still, they do nothing to address overhead noise pollution from circling police helicopters, buzzing drones, and other sources, which is the purview of the federal government, said Les Blomberg, executive director of the Noise Pollution Clearinghouse.

Public health hazard

In October 2021, the American Public Health Association declared noise a public health hazard. Decades of research links noise pollution with not only sleep disruption, but also a host of chronic conditions such as heart disease, cognitive impairment, depression, and anxiety.

“Despite the breadth and seriousness of its health impacts, noise has not been prioritized as a public health problem for decades,” the declaration says. “The magnitude and seriousness of noise as a public health hazard warrant action.”

When there’s a loud noise, the auditory system signals that something is wrong, triggering a fight-or-flight response in the body and flooding it with stress hormones that cause inflammation and can ultimately lead to disease, said Peter James, an assistant professor of environmental health at Harvard University’s T.H. Chan School of Public Health.

Constant exposure to noise increases the risk of heart disease by 8% and diabetes by 6%, research shows. The European Environment Agency estimated in 2020 that noise exposure causes about 12,000 premature deaths and 48,000 cases of heart disease each year in Western Europe.

While California Highway Patrol officials will spend the next few years researching noise cameras, they acknowledge that noise from street racing and so-called sideshows — where people block off intersections or parking lots to burn out tires or do “doughnuts” — has surged over the past several years and disturbs people right now.

Cars in California are supposed to operate at 95 decibels — a little louder than a leaf blower or lawn mower — or less. But drivers often modify their cars and motorcycles to be louder, such as by installing “whistle tips” on the exhaust system to make noise or removing mufflers.

In 2021, the last full year for which data is available, the highway patrol issued 2,641 tickets to drivers for excessive vehicle noise, nearly double 2018’s 1,400 citations.