Working in noisy environment raises risk of high blood pressure: study

By Stephen Beech via SWNS

Working in a noisy environment such as a factory raises the risk of high blood pressure, according to new research.

The danger increases 10% for each year worked on noisy industrial machinery, say scientists.

Persistent noise exposure at work has already been linked to hearing loss, reduced concentration plus physical and psychological stress.

The new study found in adult power looms weavers, chronic noise exposure not only increased their blood pressure overall but also each year of exposure increased their odds of having high blood pressure by 10%.

Study lead author Dr. Golam Dastageer Prince said: “While the mechanism is still not well-explored, it is thought that the stress response by the body to chronic sound exposure causes hormonal imbalances that gradually lead to a permanent elevation of blood pressure.

“High blood pressure impacts more than a billion people worldwide and just one in five have it under control, yet it is a major cause of premature death.

"In addition to treating the high blood pressure through appropriate means, we must find ways to mitigate the exposure to the noise if we want to reduce the cardiovascular risk of these patients.”

Researchers at the Directorate of General Health Services (DGHS) in Bangladesh looked at 289 adult workers in selected weaving factories in the city of Narayanganj from January to December 2023.

Participants took part in a face-to-face interview to complete a questionnaire covering socio-demographic factors, behavior, dietary habits and family medical history.

Blood pressure, height, weight and noise intensity were measured following standard procedures by the researchers.

The participants were predominantly male and married and were an average of around 34 years of age.

A "notable" proportion of the participants were illiterate, according to the research team.

Workplace exposure duration averaged nearly 16 years, with noise intensity ranging from 96 to 111 decibels.

The recommended exposure limits for occupational noise exposures are 85 decibels on average over an eight-hour workday, according to the National Institute for Occupational Safety and Health in the United States. Sounds at or below 70 decibels are generally considered safe.

Dr. Prince, medical officer at DGHS Bangladesh, said none of the participants was found to be wearing ear protection.

He said: “Hopefully we can raise awareness of not only noise-induced hearing loss, but the impact of noise on blood pressure and workers’ behaviors and attitudes towards using personal protective equipment.

“Pushing for structural improvements to industries may also help us improve the health safety of these workers.”

The participants had a 31.5% rate of high blood pressure with an additional 53.3% being pre-hypertensive.

The study also found a positive correlation between blood pressure and noise exposure duration.

Each year of exposure was found to increase high blood pressure odds by 10%, even after adjusting for age, body mass index (BMI) and whether the participants smoked or not.

Dr. Prince said: “As the study focused on workers exposed to more than 85 decibels noise for long periods of time, any profession causing workers to experience similar exposure might experience similar blood pressure impacts."

He added: “We definitely need more exploratory studies to reveal more information about the potential mechanisms and long-term health outcomes.”

Dr. Prince said recent studies have shown that living near noise pollution - including busy roads, trains and air traffic - can have an impact on cardiovascular health. But the current study may not apply to noise experienced during daily life.

He said noise pollution experienced near home usually ebbs and flows, while the industrial exposures in the study are typically continuous in pattern due to the machinery and remain at a constant sound level.

The findings are due to be presented at the American College of Cardiology (ACC) Asia 2024 conference in Delhi, India.