Medical and scientific news

Massachusetts Medical Society: No to noisy leaf blowers

Photo credit: Hector Alejandro licensed under CC by 2.0

By Jamie L. Banks, PhD, MSc, Program Director, The Quiet Coalition

Are health concerns about gas-powered leaf blowers (GLBs) gaining momentum? On April 29th, the Massachusetts Medical Society (MMS) became the second in the nation to approve a resolution against GLBs, following the lead of the Medical Society of the State of New York (MSSNY). Other physician groups, such as Utah Physicians for Healthy Environment and Fresno Madera Medical Society, have also issued warnings on the use of GLBs and other fuel-powered lawn and garden equipment. The resolution brought by the society’s Committee on Environmental and Occupational Health and its chair Heather Alker, MD, MPH, recommends that the MMS:

  • Recognize noise pollution as a public health hazard, with respect to hearing loss;
  • Support initiatives to increase awareness of the health risks of loud noise exposure;
  • Urge the maximum feasible reduction of all forms of air pollution, including particulates, gases, toxicants, irritants, smog formers, and other biologically and chemically active pollutants; and
  • Acknowledge the increased risk of adverse health consequences to workers and general public from gas-powered leaf blowers including hearing loss and cardiopulmonary disease.

The growing concern on the part of the medical community over leaf blower noise is welcome news. Commercial GLBs can produce noise of 95 decibels and higher at the ear of the operator. This noise level exceeds safe occupational levels by an order of magnitude. The close proximity use of these powerful engines exposes both workers and others in the area to prolonged periods of excessive noise, not to mention toxic air pollutants. The presence of a low frequency component in the leaf blower’s frequency band distribution (i.e., the device’s sound signature) enables it to travel over long distances and through walls and windows.

The MMS resolution notes the harms to hearing and health from excessive noise produced by GLBs. Loud noise is known to cause hearing loss, tinnitus, and hyperacusis, as well as other health problems such as high blood pressure and heart disease. In addition, loud noise has negative effects on quality of life, communication and social interaction, work productivity, and psychological well-being.

The burgeoning use of GLBs and other fossil fuel powered equipment around our homes, schools, and other public spaces is a public health hazard, and a growing number of physicians and other health professionals are becoming concerned. The moves made by MMS and MSSNY are to be lauded, and other state societies and medical groups, including the American Lung Association and American Heart Association, need to prioritize this issue.  With the body of scientific evidence on the harms associated with noise and pollution, other state and national medical societies have a critical role to play in educating government officials and the public about the connections between environmental hazards and disease and the actions we can take to reduce risks in our communities.

Jamie L. Banks, PhD, MSc, is the Executive Director of Quiet Communities, Inc. and the Program Director of The Quiet Coalition. She is an environmentalist and health care scientist dedicated to promoting clean, healthy, quiet, and sustainable landscape maintenance, construction, and agricultural practices. Dr. Banks has an extensive background in health outcomes and economics, environmental behavior, and policy.

Source: Quiet Communities

Originally posted at The Quiet Coalition.

National Parks: Why quiet matters

By David Sykes, Vice Chair, The Quiet Coalition

On May 4, Science and Phys.org™ published news reports about a recent, significant, multi-year study about the pervasiveness of noise pollution in 492 national parks and natural areas across the U.S.

In “Noise Pollution is invading even the most protected natural areas,” Science writer Ula Chrobak notes that:

The great outdoors is becoming a lot less peaceful. Noise pollution from humans has doubled sound levels in more than half of all protected areas in the United States—from local nature reserves to national parks—and it has made some places 10 times louder, according to a new study. And the cacophony isn’t just bad for animals using natural sounds to hunt and forage—it could also be detrimental to human health.

Under the study, researchers from the National Park Service and Colorado State University “recorded noise at 492 sites across the country with varying levels of protection, [and] used the recordings to predict noise throughout protected areas in the rest of the country.” They also estimated naturally occurring ambient noise and compared the noise levels with and without humanmade noise. The results were damning: noise pollution doubled sound levels in 63% of protected areas and caused a 10-fold increase in 21% of protected areas.

And the impacts of that noise pollution affect all living things withing these areas.  Phys.org reports interviews Rachel Buxton, the study’s lead author and post-doctoral researcher, who states that “[t]he noise levels we found can be harmful to visitor experiences in these areas, and can be harmful to human health, and to wildlife.” The noise pollution findings means that “noise reduced the area that natural sounds can be heard by 50 to 90 percent,” which “also means that what could be heard at 100 feet away could only be heard from 10 to 50 feet.”

So what is the impact on humans and wildlife?  Phys.org explains:

This reduced capacity to hear natural sound reduces the restorative properties of spending time in nature, such as mood enhancement and stress reduction, interfering with the enjoyment typically experienced by park visitors. Noise pollution also negatively impacts wildlife by distracting or scaring animals, and can result in changes in species composition.

High levels of noise pollution were also found in critical habitat for endangered species, namely in endangered plant and insect habitats. “Although plants can’t hear, many animals that disperse seeds or pollinate flowers can hear, and are known to be affected by noise, resulting in indirect impacts on plants,” said Buxton.

The study results have been widely reported, showing that there is real interest in protecting our national parks and natural areas.  Researchers know that “many people don’t really think of noise pollution as pollution,” but they hope that this study will encourage more people to “consider sound as a component of the natural environment.”

The National Park Service’s huge portfolio of parks and natural areas provides a huge canvas for researchers concerned about the impacts of “noise pollution.” You may be surprised to learn that the National Park Service has a research division called “Natural Sounds and Night Skies Division” that has been looking for several years at the effects of noise not only on visitor experiences, but also on plants and animals. Their work is fascinating and resulted in a 2014 report from the National Academy of Engineering called “Preserving National Park Soundscapes.

David Sykes chairs/co-chairs four national professional groups in acoustical science: The Acoustics Research Council, ANSI S12 WG44, The Rothschild Foundation Task Force on Acoustics, and the FGI Acoustics Working Group. He is also a board member of the American Tinnitus Association, co-founder of the Laboratory for Advanced Research in Acoustics (LARA) at Rensselaer Polytechnic Institute, lead author of “Sound & Vibration 2.0 (2012, Springer-Verlag), and a contributor to “Technology for a Quieter America” (2011, National Academy of Engineering). A graduate of the University of California/Berkeley with graduate degrees from Cornell University, he is a frequent organizer of and speaker at professional conferences in the U.S., Europe, Asia, and the Middle East.

Feeling a bit stressed? Maybe this will help.

It’s true: The sound of nature helps us relax.  Researchers at the Brighton and Sussex Medical School (BSMS) have “found that playing ‘natural sounds’ affected the bodily systems that control the flight-or-fright and rest-digest autonomic nervous systems, with associated effects in the resting activity of the brain.” Science Daily reports that “[w]hile naturalistic sounds and ‘green’ environments have frequently been linked with promoting relaxation and wellbeing, until now there has been no scientific consensus as to how these effects come about.”

The researchers “conducted an experiment where participants listened to sounds recorded from natural and artificial environments,” during which their brain activity was measured and autonomic nervous system activity was monitored. The research team found that activity in the “default mode network of the brain (a collection of areas which are active when we are resting) was different depending on the sounds playing in the background.” Long and short, when listening to natural sounds “the brain connectivity reflected an outward-directed focus of attention,” whereas artificial sounds caused the brain connectivity to reflect “an inward-directed focus of attention, similar to states observed in anxiety, post-traumatic stress disorder and depression.”  Interestingly, the change in brain activity depended on the participant’s stress level–those showing the greatest stress before the experiment “showed the greatest bodily relaxation when listening to natural sounds,” but those who were already relaxed showed “a slight increase in stress” when “listening to natural compared with artificial sounds.”

While helpful for treating people with anxiety, the study results will have a much greater reach. Science Daily notes that “the study of environmental exposure effects is of growing interest in physical and mental health settings, and greatly influences issues of public health and town planning.” Could a restful natural spot will be coming to your town?

Link via UK Noise Association.

Top researchers work toward treatments, but prevention remains the best medicine.

By Daniel Fink, MD, Chair, The Quiet Coalition

Humans are born with only 15,000 cochlear hair cells. When these are destroyed by noise they don’t regenerate, unlike cochlear hair cells in other animals, such as chickens. If a way can be found to regenerate human cochlear hair cells, perhaps hearing can be restored.

A recent report from Harvard and MIT holds promise for treating hearing loss in the future. Researchers there were able to increase the number of stem cells from mouse cochlear hair cells in vitro using a cocktail of small-molecule chemicals. It’s hard to do basic science research on humans–one can’t hurt people doing research–but mice share 99% of our genetic material, and being small and inexpensive, they are good substitutes in the lab. The researchers hope to begin testing their approach in humans in 18 months.

This is great news for millions of Americans with hearing loss. It’s possible that with additional advances, one day their hearing could be restored. But I have one problem with the report: The researchers are developing a treatment, probably not an inexpensive one, for a problem that is entirely preventable.

The public health mantra is that prevention is always better and cheaper than treatment, which in turn is better and cheaper than rehabilitation. Noise-induced hearing loss is 100% preventable. How? Avoid loud noise. If you can’t avoid noise exposure, use hearing protection (earplugs and ear muff hearing protective devices). You can find these in your drugstore, in “big box” home improvement stores like Home Depot or Lowe’s, or online. There is even an online retailer devoted only to hearing protection.

So kudos to the researchers at Harvard and MIT. No doubt their work and the work of other researchers will eventually help the millions of Americans who already suffer from hearing loss and other hearing damage. But let’s put time, money, and effort in promoting a cheaper and safer approach to hearing health–prevention. No more research is needed, and we can avoid hearing loss today.

Dr. Daniel Fink is a leading noise activist based in the Los Angeles area.  He serves on the board of the American Tinnitus Association and is the interim chair of Quiet Communities’s Health Advisory Council and the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America.

Originally posted at The Quiet Coalition.

Progress Made Against Hospital Noise

By The Quiet Coalition

Some people care most about airport noise. Others focus on noise in schools or restaurants or stadiums. But one group of about 500 professionals has spent twelve years reducing noise in America’s hospitals and healthcare facilities.

Of course, airport noise is a public health problem—especially for people living near America’s 5,194 airports–but noise is a serious public health problem indoors too. This is particularly so for people whose health is compromised, i.e., the millions of patients in America’s 62,414 hospitals and healthcare facilities, not to mention the quarter-million medical and support staff who work there amid the din.

Healthcare facilities are oftentimes the noisiest, most sleep-deprived places you will find anywhere. Have you tried sleeping in an older-style hospital recently? Furthermore, the noise problem has escalated steadily for decades thanks to the burgeoning use of new technologies such as alarmed medical devices.

Fortunately, a group of about 500 professionals known as the FGI Acoustics Working Group has been working continuously for twelve years to address noise in healthcare facilities. So this story contains good news.

The group published it’s first comprehensive noise control criteria in 2010, which were quickly adopted by most states. To hear the difference, visit just about any recently constructed hospital and compare it to an older hospital.  The group’s criteria have now been “exported” to eighty-seven other countries that struggle with the same indoor noise problems (this was accomplished through partnerships with the International Code Council, the US Green Building Council’s LEED for Health Care initiative, and other groups).

But this group’s crusade against noise is not over. This November 2017, they and their hosts will publish more detailed and updated noise control criteria in three separate volumes, one covering America’s 5,564 hospitals, one for the country’s 25,750 healthcare clinics, and another one for it’s 31,100 residential care facilities. If you’re interested you can see their latest work here, FGI Bulletin #2, and here in their first edition (published in 2012).

The Quiet Coalition is proud that its chair, vice chair, and another TQC co-founder are both involved in leading this important work. According to our vice chair, David Sykes, “this decade-long work shows that a broad coalition of interested professionals–in this case, consisting of doctors, nurses, patients and families, public health advocates, hospital administrators, researchers, regulatory agency personnel, lawyers, planners, architects, engineers, designers, and contractors–can achieve meaningful, national progress toward ending the long-ignored public health problem of noise by taking a focused approach and addressing the needs of people who are particularly vulnerable.”

Originally posted at The Quiet Coalition.

Why do whales beach themselves?

A new study suggests that they are trying to escape noise, reports news.com.au. The study “has found that startled beaked whales swimming away from low frequency sonar boost their energy consumption by more than 30 per cent.” Why is this important? Because the “study showed a big difference in the energy cost of whales swimming normally and attempting to escape danger,” and suggested that “In some cases fleeing whales might run out of steam and become washed up on beaches.”

Noise is not just a nuisance.

Link via Hyperacusis Research.

Another Silent Spring

By Daniel Fink, MD, Chair, The Quiet Coalition

In 1962, Rachel Carson’s “Silent Spring” described the harmful effects of insecticides and herbicides on birds, beneficial insects, animals, and humans.  Her book helped start the environmental movement. For too many people, this will be another silent spring, caused not by a dearth of birds but because people can’t hear birds sing. They have hearing loss from another environmental pollutant, noise.

Carson described how nature’s balance controlled pest species naturally, and how these species became problems only when humans changed the environment. She noted the difference between apparent short-term safety of agrichemicals and longer-term danger. People could get sprayed with pesticides or even ingest them without apparent immediate harm, with cancer and birth defects coming later.

If Carson were alive today, she might write about noise pollution, which interferes with animal feeding, communication, mating behaviors, and navigation in forests, fields, and oceans, and causes hearing loss and other medical problems in humans.  In nature’s quiet, animals developed exquisite hearing to find food or avoid being eaten. An owl can find a mouse under a foot of snow, and zebras can hear lions approaching in the veldt.

Humans are also born with excellent hearing.  Brief exposure to loud noise usually doesn’t cause obvious auditory damage in humans, but longer or repeated exposure does. The relationship between noise and hearing loss was first noted in medieval times in bell ringers and miners, then in boilermakers during the industrial revolution.  Noise wasn’t a widespread problem, and except in large cities life was usually quiet.

Industrialization, mechanization, and urbanization made life noisier.  Noise was recognized as a public health hazard in the early days of interstate highways and jet travel, but was also considered an environmental pollutant. In 1972 Congress passed the Noise Pollution and Abatement Act, empowering the Environmental Protection Agency (EPA) to establish noise standards and require noise labeling for consumer and industrial products.

During the Reagan administration, however, Congress defunded EPA noise control activities. Little has been done since to control noise, and our country has gotten noticeably louder. Sound levels of 90-100 decibels or louder are reported in restaurants, clubs, retail stores, movie theaters, gyms, sports events, concerts, and parties, from sirens, vehicles, landscape maintenance equipment, and construction, and for those using personal music players.

The National Institutes of Health states that prolonged exposure to noise at or above 85 decibels can cause hearing loss. This is misleading, because no exposure time is given and hearing damage occurs at much lower levels. The 85-decibel standard is an occupational noise exposure standard, not a safe noise level for the public.. The EPA adjusted the occupational standard for additional noise exposure outside the workplace to calculate the noise level for preventing hearing loss to be a daily time-weighted average of only 70 decibels.

Hearing is the social sense, required for spoken communication. About 40 million American adults age 20-69 have noise induced hearing loss, half of them without noisy jobs. Why is this happening? They are exposed to loud everyday noise.  Cumulative noise exposure eventually causes hearing loss, affecting 25% of those in their 60s, half in their 70s, and 80% in their 80s, and is correlated with social isolation, depression, dementia, falls, and mortality. Due to denial, stigma, and cost only 20% of older Americans with hearing loss acquire hearing aids, after an average seven-year delay, and 40% of people with hearing aids don’t use them much, largely because hearing aids don’t help users understand speech well in noisy environments.

Preventing noise-induced hearing loss is simple: avoid loud noise. If it sounds too loud, it is too loud. Free or inexpensive smart phone sound meter apps make it easy to measure sound levels, but if one can’t converse without straining to speak or to be heard, ambient noise is above the auditory injury threshold of 75-78 decibels and auditory damage is occurring.

A quieter world is easily attainable. Whisper-quiet dishwashers, cars with quiet interiors and exhausts, the Airbus A380, and a few quiet restaurants and stores prove this.   Effective noise control technologies have long existed, including noise reduction via design and material specifications and sound insulating, isolating, reflecting, diffusing, or absorbing techniques.  Indoors, all that may be necessary is turning down the background music volume, which costs nothing.

In the 1950s and 1960s, half of all American men smoked and public spaces and workplaces were filled with tobacco smoke. When research showed that tobacco smoke caused cancer and heart disease, governments restricted smoking, leading eventually to today’s largely smoke-free society. Smokers can still smoke, but can’t expose others involuntarily to their smoke.

Noise causes hearing loss. Governments should set and enforce indoor and outdoor noise standards, to reduce each person’s daily noise dose. Adults have the right to make and listen to all the noise they want, but not where others can hear them. If we can breathe smoke-free air, we can make a quieter world, so future generations won’t have to endure another silent spring.

Dr. Fink is a leading noise activist based in the Los Angeles area.  He serves on the board of the American Tinnitus Association and is the interim chair of Quiet Communities’s Health Advisory Council and the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America.

Originally posted at The Quiet Coalition.

Hearing loss may double in the U.S. by 2060

Photo credit: Thomas Widmann

CBS News reports on a new study that concludes that millions of Americans face the prospect of losing their hearing as they age. The study by researchers at Johns Hopkins University estimates that “[a]mong American adults 20 and older, hearing loss is expected to increase from 44 million in 2020 (15 percent of adults) to 73.5 million by 2060 (23 percent of adults),” with the greater increase among older Americans. As a result, “there will be an increased need for affordable interventions and access to hearing health care services.”  Says lead study author Adele Goman, “[h]earing loss is a major public health issue that will affect many more adults,” and “to address this issue, novel and cost-effective approaches to hearing health care are needed.”

Or perhaps prevention would be a better tactic?

Dr. Debara Tucci, a spokesperson for the American Academy of Otolaryngology, Head and Neck Surgery, would agree. She tells CBS News that “people aren’t doomed to lose their hearing as they age.” “The most common cause of hearing loss is prolonged exposure to loud noise,” adds Dr. Tucci, “which includes loud music and a noisy workplace.”  Prevention, then, should be a rallying call among the medical profession, particularly public health officials.  This is especially important since the litany of horribles that befalls older adults who suffer hearing loss goes well beyond difficulty hearing.  The list includes: higher incidences of depression and anxiety, higher rates of hospitalization and of falls, and even “evidence of an association between hearing loss and mental decline.”

Coupled with the recently released and updated information concerning hearing loss from the Centers for Disease Control and Prevention, this study is a wake-up call to the medical and audiology professions and the public. Simply put, there is a low-cost and 100% effective way to tackle noise-induced hearing loss–preventing it from occurring in the first instance.

 

 

 

Red wine and dark chocolate can protect against hearing loss?

Sign me up! Ok, a red wine and dark chocolate diet may sound pretty fabulous, but obviously one cannot embrace it as a way of life no matter how concerned you are about your hearing. And, in any event, Debbie Clason’s post at Healthy Hearing adds that while “a glass or two of red wine can guard against the type of inflammation that causes [noise-induced hearing loss], excessive drinking deposits toxic levels of alcohol in your bloodstream which can permanently damage your hearing.” As for the protective benefits of dark chocolate, it’s not the chocolate in dark chocolate that protects hearing.  Rather, chocolate “contains zinc, which is known for boosting the immune system and guarding against infections that plague the ear.”

So, as with most other things, enjoy some red wine and dark chocolate in moderation.  And who knows?  It may actually help to protect your hearing.

Click the first link above to learn more about inflammation, hearing loss, and how “[h]ealthy eating and exercise habits, combined with reducing exposure to excessive environmental and occupational noise, can help preserve hearing acuity into old age.”

The world sounds different than it did a century ago

and it’s not for a good reason. Claire Asher, BBC, reports on how climate change and animal extinctions have altered the way our world sounds.  Asher writes that human activity is changing our natural soundscape irreversibly:

In 2015, a US team of scientists and engineers reported that the loudest sound in some waters now comes from millions of tiny bubbles, which are released by melting glaciers and icebergs. In the fjords of Alaska and Antarctica, the average noise level is now over 100 decibels – louder than any ocean environment recorded before.

And it is more than our oceans that are affected.  Asher notes that “natural spaces are now polluted with human-made noises. As we change forests into farms and drive species to extinction, we are fundamentally changing how our world sounds.”

Click the first link to read this interesting, if depressing, article.

Link via @jeaninebotta.