Masks hanging in backyard to dry.

UCLA-led Research Finds Connections Between Air Quality and COVID Vulnerability

Even as governments across the United States consider lifting mask mandates and relaxing preventative measures as vaccination numbers creep up, new research from a UCLA-led team has found that such basic techniques significantly reduce the risk of getting COVID-19.

In addition, the research found that U.S. counties with higher exposures to poor air quality, historically, saw higher county-level COVID-19 mortality rates in 2020, with a 7.6% increase in in COVID-19 risk with a one-unit increase of 2.5 micrometers (µm), or PM2.5. The use of preventative measures – like stay home orders and masking – reduced the risk of COVID-19 by 8% and 15%, respectively, but did not reduce the increase of incidence in counties with poor air quality.

“This is evidence that long-term exposure to poor air quality increased the risk of COVID-19, during each surge, and cumulatively, in the United States,” said Dr. Zuo-Feng Zhang, UCLA Fielding School of Public Health (FSPH) distinguished professor of epidemiology and associate dean for research. “And although both state-level implementation of facemasks mandates and stay home orders were effective in preventing the spread of COVID-19, no clear effects were observed in terms of long-term exposure to fine particulate matter.”

The research – “Long-Term Exposure to PM2.5, Facemask Mandates, Stay Home Orders and COVID-19 Incidence in the United States” – is being published in the June edition of the peer-reviewed International Journal of Environmental Research and Public Health. The co-authors include researchers from UCLA, FSPH, the David Geffen School of Medicine at UCLA, and the State University of New York, Buffalo.

Both the importance of improving air quality and protective measures should be considered as among the “lessons learned” from the pandemic for policy makers and the public, said Dr. Jody Heymann, a UCLA distinguished professor of public health, public policy, and medicine, and a co-author.

“The burden of environmental risks is grossly unequal in the US and globally,” said Heymann, a physician and public policy expert who serves as director of the UCLA Fielding School of Public Health’s WORLD Policy Analysis Center. “This study raises profound concerns about one more way that elevated exposure to air pollutants likely has serious consequences for the health of all people in the US and fuels health inequalities experienced by communities of color and low-income communities. There is an urgent need to lower the long-term exposure to fine particulate matter for those with the greatest exposure in the U.S. and to create a healthy environment across all locations where adults live and work and children learn and play.”

Fine particulate matter, defined as inhalable pollutant-derived particles with a diameter equal to or less than 2.5 micrometers, has been linked to heart and lung diseases, including asthma. The risks are severe, despite the tiny size of the particles, authors said.

“How small is 2.5 micrometers? Think about a single hair from your head,” said Clairy Fang, a doctoral candidate with the FSPH department of epidemiology and a co-author. “The average human hair is about 70 micrometers in diameter – 30 times larger than the largest fine particle.”

Some 3,096 counties across the United States were included in the study; as of 12 September 2020, the average COVID-19 incidence in the U.S. was 2.6%, with a median of 1.27%. Counties with COVID-19 incidence greater than the national median had higher average fine particulate matter concentrations, earlier occurrences of the first case, more tests performed, and were less likely to reopen.

“The health problems, in turn, appear to be connected with increased susceptibility to COVID-19 via chronic respiratory inflammation, which predisposes individuals to the disease; increased vulnerabilities to any viral infection, including COVID,” said Dr. Jianyu Rao, FSPH professor of epidemiology and pathology. “Air pollution could lead to the over-expression of angiotensin-converting enzyme 2 (ACE2), which is the receptor SARS-CoV-2 binds to, thus increasing susceptibility to infection.”

Higher population densities, higher proportions of African American and Hispanic residents, a larger percentage of people living in poverty, higher populations with less than a high school education, and fewer owner-occupied properties were found in the counties with increased incidences of COVID-19.

“This is the first study to examine how the association between long-term exposure to fine particulate matter and COVID-19 incidence may be affected by state prevention policies, including facemask mandates and stay home policies,” said Dr. Yifang Zhu, FSPH professor of environmental health sciences and senior associate dean for academic programs. “Importantly, this study suggests a very real mitigation effect of stay home and face mask policies; facemask mandates, in fact, showed stronger protective effects toward the later course of the pandemic – exactly where we are today.”

The study is subject to some limitations, the authors said, including that both exposure and COVID-19 incidence are measured at county/state level, not at individual level. Overall, however, these findings show that long-term exposure to fine particulate matter is a risk factor, and that the levels of exposure to in the U.S. are sufficiently high to increase the risk of COVID-19.

“Although 43% of the US population has been vaccinated and many of the states have been reopened and planned to reopen, individuals who have not yet vaccinated or not fully vaccinated will be at a high risk of infection by emerging COVID-19 variants,” said Dr. Lina Mu, with the SUNY Buffalo and a co-author. “These individuals should still practice face covering and social distancing to protect themselves from infection before they are fully vaccinated.”

Funding: This research was funded by National Cancer Institute grant number NIH/NCI T32 CA009142.

Data availability statement: All data analyzed are publicly accessible, and the sources are listed here:

Citation: Fang, Fang; Mu, Lina; Zhu, Yifang; Rao, Jianyu; Heymann, Jody; Zhang, Zuo-Feng. 2021. “Long-Term Exposure to PM2.5, Facemask Mandates, Stay Home Orders and COVID-19 Incidence in the United States” Int. J. Environ. Res. Public Health 18, no. 12: 6274.

The UCLA Fielding School of Public Health, founded in 1961, is dedicated to enhancing the public’s health by conducting innovative research, training future leaders and health professionals from diverse backgrounds, translating research into policy and practice, and serving our local communities and the communities of the nation and the world. The school has 631 students from 26 nations engaged in carrying out the vision of building healthy futures in greater Los Angeles, California, the nation and the world.

Originally published June 16, 2021 by UCLA Fielding School of Public Health at .

Image by Chris Zúniga

Rapid measurement of aerosol volatility using a deep learning-based portable microscope

Exposure to particulate matter (PM) has been associated with various adverse health effects. A large fraction of these particles consists of volatile or semi-volatile materials, such as emissions generated from cooking, automobiles and tobacco products. The dynamics of the evaporation process of such volatile particles has been an active area of research since the 19th century. However, existing measurement methods are either low throughput or unable to provide direct volatility measurement of particulate matter.

A team of UCLA engineers and environmental health scientists created a new method that can directly measure the volatility of particulate matter using a portable microscope that is powered by deep learning. UCLA team’s volatile particle measurement system is based on a cost-effective and mobile air quality monitoring device that records holographic images of aerosols that are captured on a transparent sticky sampling pad. These acquired holograms are then rapidly reconstructed using a deep neural network to dynamically image the evaporation process of aerosols and measure their volatility constants.

In their recent manuscript published in ACS Sensors, a journal of the American Chemical Society, researchers applied this volatility measurement system to characterize aerosols that are generated by electronic cigarettes (e-cigs). E-cigs have gained worldwide attention, primarily due to their unprecedented popularity over the last decade among never-smoking adolescents and young adults. The use of an e-cig generates an inhalable aerosol by heating and vaporizing a special liquid (also known as e-liquid), which typically uses propylene glycol and vegetable glycerin as the solvents to dilute nicotine and flavoring compounds. The UCLA team revealed a negative correlation between e-cig generated particle volatility and vegetable glycerin concentration in the e-liquid. Furthermore, the addition of other chemicals, such as nicotine and flavoring compounds, reduced the overall volatility of e-cig generated aerosols.

“The presented device can help us better examine the dynamic behavior of e-cig aerosols in a high-throughput manner, potentially providing important information for e-cig exposure assessment via, for example, second-hand vaping. This new method can also be broadly applied to rapidly characterize other types of volatile particulate matter” said Dr. Aydogan Ozcan, the Chancellor’s Professor of Electrical and Computer Engineering at UCLA and an associate director of the California NanoSystems Institute, who is the senior corresponding author of the work.

This research was led by Dr. Ozcan, in collaboration with Dr. Yifang Zhu, a Professor of Environmental Health Sciences (EHS) at UCLA. The other authors of this work are graduate students Yi Luo, Yichen Wu, Liqiao Li, Yuening Guo and Ege Çetintaş. Dr. Ozcan also has UCLA faculty appointments in bioengineering and surgery, and is an HHMI professor.

Link to paper:

Article by Maxim Batalin. Image by Ozcan labs. Originally published June 10, 2021 at

Indoor air purifier

As schools spend millions on air purifiers, experts warn of overblown claims and harm to children

Last summer, Global Plasma Solutions wanted to test whether the company’s air-purifying devices could kill COVID-19 virus particles but could find only a lab using a chamber the size of a shoebox for its trials. In the company-funded study, the virus was blasted with 27,000 ions per cubic centimeter.

In September, the company’s founder incidentally mentioned that the devices being offered for sale actually deliver a lot less ion power — 13 times less — into a full-sized room.

The company nonetheless used the shoebox results — over 99% viral reduction — in marketing its device heavily to schools as something that could combat COVID in classrooms far, far larger than a shoebox.

School officials desperate to calm worried parents bought these devices and others with a flood of federal funds, installing them in more than 2,000 schools across 44 states, a KHN investigation found. They use the same technology — ionization, plasma and dry hydrogen peroxide — that the Lancet COVID-19 Commission recently deemed “often unproven” and potential sources of pollution themselves.

In the frenzy, schools are buying technology that academic air-quality experts warn can lull them into a false sense of security or even potentially harm kids. And schools often overlook the fact that their trusted contractors — typically engineering, HVAC or consulting firms — stand to earn big money from the deals, KHN found.

Academic experts are encouraging schools to pump in more fresh air and use tried-and-true filters, like HEPA, to capture the virus. Yet every ion- or hydroxyl-blasting air purifier sale strengthens a firm’s next pitch: The device is doing a great job in the neighboring town.

“It’s a self-fulfilling prophecy. The more people buy these technologies, the more they get legitimacy,” said Jeffrey Siegel, a civil engineering professor at the University of Toronto. “It’s really the complete wild west out there.”

Marwa Zaatari, a member of the American Society of Heating, Refrigerating and Air-Conditioning Engineers’ (ASHRAE) Epidemic Task Force, first compiled a list of schools and districts using such devices.

Schools have been “bombarded with persistent salespersons peddling the latest air and cleaning technologies, including those with minimal evidence to-date supporting safety and efficacy” according to a report released Thursday by the Center for Green Schools and ASHRAE.

Zaatari said she was particularly concerned that officials in New Jersey are buying thousands of devices made by another company that says they emit ozone, which can exacerbate asthma and harm developing lungs, according to decades of research.

“We’re going to live in a world where the air quality in schools is worse after the pandemic, after all of this money,” Zaatari said. “It’s really sickening.”

The sales race is fueled by roughly $193 billion in federal funds allocated to schools for teacher pay and safety upgrades — a giant fund that can be used to buy air cleaners. And Democrats are pushing for $100 billion more that could also be spent on air cleaners.

WATCH: What impact is ‘the COVID slide’ having on students?

In April, Global Plasma Solutions said further tests show its devices inactivate COVID in the air and on surfaces in larger chambers. The company studies still use about twice the level of ions than its leaders have publicly said the devices can deliver, KHN found.

There is virtually no federal oversight or enforcement of safe air-cleaning technology. Only California bans air cleaners that emit a certain amount of ozone.

U.S. Rep. Robert “Bobby” Scott (D-Va.), chair of the education and labor committee, said the federal government typically is not involved in local decisions of what products to buy, although he hopes for more federal guidance.

In the meantime, “these school systems are dealing with contractors providing all kinds of services,” he said, “so you just have to trust them to get the best expert advice on what to do.”

These go-between contractors — and the air cleaner companies themselves — have a stake in the sales. While their names might appear in school board records, their role in selling the device or commission from the deal is seldom made public, KHN found.

A LinkedIn job ad with the logo for one air purifier company, ActivePure Technology, which employs former Trump adviser Dr. Deborah Birx as its chief medical and science adviser, recruited salespeople this way: “Make Tons of Money with this COVID-killing Technology!!” The commission, the post said, is up to $900 per device.

“We have reps [who] made over 6-figures in 1 month selling to 1 school district,” the ad says. “This could be the biggest opportunity you have seen!”

‘A tiny bit of ozone’

Schools in New Jersey have a particularly easy time buying air cleaners called Odorox: A state education agency lists them on their group-purchasing commodity list, with a large unit selling for more than $5,100. Originally used in home restoration and mold remediation, the devices have become popular in New Jersey schools as the company says its products can inactivate COVID.

In Newark, administrators welcomed students back to class last month with more than 3,200 Odorox units, purchased with $7.5 million in federal funds, said Steven Morlino, executive director of Facilities Management for Newark Public Schools.

“I think parents feel pretty comfortable that their children are going to a safe environment,” he said. “And so did the staff.”

Environmental health and air-quality experts, though, are alarmed by the district’s plan.

The Pyure company’s Odorox devices are on California air-quality regulators’ list of “potentially hazardous ozone generators sold as air purifiers” and cannot be sold in the state.

The company’s own research shows that its Boss XL3 device pumps out as much as 77 parts per billion of ozone, a level that exceeds limits set by California lawmakers for the sale of indoor air cleaners and the EPA standard for ground-level ozone — a limit set to protect children from the well-documented harm of ozone to developing lungs.

That level exceeds the industry’s self-imposed limit by more than 10 times and is “unacceptable,” according to William Bahnfleth, an architectural engineering professor at Penn State who studies indoor air quality and leads the ASHRAE Epidemic Task Force.

Jean-Francois “JF” Huc, CEO of the Pyure company, pointed out that the company’s study was done in a space smaller than they would recommend for such a powerful Odorox device. He cautioned that it was done that way to prove that home-restoration workers could be in the room with the device without violating work-safety rules.

“We provide very stringent operating guidelines around the size of room that our different devices should be put in,” he said. But school staffers are often not warned about the problems they could face if a too-powerful device is used in a too-small room, he acknowledged.

You can’t see or smell ozone, but lungs treat it like a “foreign invader,” said Michael Jerrett, who has studied its health effects as director of the UCLA Center for Occupational and Environmental Health.

Lung cells mount an immune-like response, which can trigger asthma complications and divert energy from normal lung function, he said. Chronic exposure has been linked to more emergency room visits and can even cause premature death. Once harmed, Jerrett said, children’s lungs may not regain full function.

“Ozone is a very serious public health problem,” Jerrett said.

By Lauren Weber and Christina Jewett of Kaiser Health News. First published by PBS News Hour on May 3, 2021.
Read  the full article at
Featured image by Aaron Yoo

workers maintaining a gas line

Natural gas leak that disrupted Downey and caused evacuations will extend overnight

Downey residents affected by a natural gas leak Thursday should expect evacuations to continue overnight, officials said.

The leak prompted a small evacuation but a wide warning alert after a contractor cut a gas main in a residential area, authorities said.

Downey’s fire and police departments arrived at Stewart and Gray Road and Rives Avenue at 10:32 a.m., said Tracy Gonzales, the Fire Department’s supervisor of communications. Southern California Gas responded shortly after and have worked with first responders to stop the flow of gas from the severed 6-inch main line.

At 3 p.m., SoCalGas estimated it would take four hours to cap the leak, said Juddy Montenegro, Downey’s public information officer. At about 8:30 p.m., the fire officials said repairs would take another eight hours.

Police have secured the area and road closures are in place on Stewart and Gray Road from Paramount Boulevard to Rives Avenue.

A 300-foot evacuation zone was set up around the leak. Montenegro said about 40 households were affected by the evacuation orders.

No injuries have been reported, but the department is providing shelter for those evacuated to shield them from the light rain, Gonzales said. Residents in the area may smell a natural gas odor while crews work, SoCalGas said in a statement.

As of 1 p.m., Los Angeles County’s large vaccination site in Downey was still open and unaffected by the leak.

An emergency alert was issued about 12:35 p.m., notifying L.A. County residents to avoid the area. Montenegro said the city was “testing a new system” but the alert was only intended for residents near the area.

“Unfortunately, it went out to more people,” she said.

Michael Jerrett, a professor of environmental health sciences at UCLA’s Fielding School of Public Health, said that the short duration of the evacuation order and the size of the evacuation zone signaled that there wouldn’t be a high concentration of air toxins that could endanger returning residents. But he did advise that residents open windows to increase the air flow in their homes.

“I wouldn’t be concerned about going back to my own house if it was the same circumstances,” he said.

Read the full article at:…

By Priscella Vega and Sammy Roth originally published April 22, 2021

Picture by Baltimore Sun

image of factory smoke

‘She Coughs When She’s Sleeping’: Life In Polluted Pacoima

When Amanda Rivera was diagnosed with asthma as a child, everyone told her she’d grow out of it. Instead, Rivera feels like she grew into it.

“It just got worse as I got older,” Rivera said. “I’ve been to like so many doctors, specialists and no one has been able to get rid of the cough.”

For her whole life, Rivera has lived in the same house in the east San Fernando Valley neighborhood of Pacoima, a region with poor air quality in already smoggy L.A. county. Over the years, she’s accrued a tote bag-full of asthma equipment: daily inhalers, rescue inhalers, and nebulizer machines. For Rivera, asthma is just part of her routine.

“Lost cause,” she laughs, then inhales deeply to catch her breath.

Her younger brother, Aaron Ortiz, can’t remember his sister without the condition. It’s part of how he recognizes her.

“She’s always coughing. That’s how you know she’s home,” Ortiz said. “She coughs when she’s sleeping… she can’t laugh without coughing.”

Ortiz took a particular interest in his sister’s condition as a UC Santa Cruz environmental science student. For one class, he researched Pacoima’s history of redlining, industry and high rates of respiratory problems.

“It just hit me… that’s like describing my life,” Ortiz said.

His sister doesn’t hold it against her hometown’s air for possibly causing and likely exacerbating her asthma. But Ortiz definitely does.

“It’s like this weird pain and anger, knowing that, like, you and your family are statistics,” he said.

Pacoima Businesses Are Big Producers Of Chemicals

According to Michael Jerrett, a UCLA public health professor, Pacoima faces multiple challenges when it comes to air quality. For starters, the geography of the region, a valley, causes air-toxic chemicals, like nitrogen dioxide and ozone to settle near ground level. It’s like liquid in a bowl. That’s where small particles get into people’s lungs, where they can cause inflammation.

Read the full article at:

By Caroline Champlin originally published April 22, 2021

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caution sign that reads "Pesticide spraying in progress: proceed at own risk" in front of blooming plants

Childhood Brain Tumors Linked to Mother’s Exposure to Pesticides

Research published in the peer-reviewed journal Environmental Research suggests that exposure during pregnancy to a wide variety of pesticides may lead to the development of central nervous system tumors during childhood.

And the increased risk of these tumors – estimated as much as twice to 2.5 times higher for some pesticides – occurs even if the mother is not a farmworker, but lived as much as 2.5 miles (4000 meters) away from the field where the pesticides are sprayed, researchers found.

“Exposure to certain pesticides, simply through residential proximity to agricultural applications during pregnancy, may increase the risk of childhood central nervous system tumors,” said Dr. Beate Ritz, UCLA Fielding School of Public Health (FSPH) professor of epidemiology and of environmental health sciences, one of the co-authors. “Policy interventions to reduce pesticide exposure in individuals residing near agricultural fields should be considered to protect the health of children.”

The research – “Residential Proximity to Pesticide Application as a Risk Factor for Childhood Central Nervous System Tumors” – is being published in an upcoming edition of the peer-reviewed journal Environment Research, and is available on-line. Pesticides have been investigated as possible risk factors for childhood cancer since the 1970s, and the U.S. Environmental Protection Agency has classified more than 100 as possible or probable carcinogens, based on toxicological and epidemiological data.

“Many pesticides are neurotoxicants, and have even been found in cord blood, indicating placental transfer of these toxins to the developing fetus,” said co-author Shiraya Thompson, an epidemiology MS candidate at FSPH. “This, in turn, suggests prenatal pesticide exposure may increase childhood brain cancer risk.”

This latest work, however, is the first study to track exposure and estimate risks of 77 separate and specific pesticides, said co-author Dr. Julia Heck, associate dean for research at the University of North Texas College of Health and Public Service and an associate professor of epidemiology at FSPH.

“This study is the first, to our knowledge, to estimate effects for a large number of specific pesticides in relation to CNS tumor subtypes,” Heck said. “Our results suggest that exposure to specific pesticides may best explain the results of previous studies that reported relationships between broader pesticide types and central nervous system tumors.”

The research team, from UCLA, Cedars-Sinai Medical Center, and the University of Southern California, all in Los Angeles, and the University of North Texas, analyzed cases of childhood central nervous system tumors in California between 1998 and 2013, with a focus on those living near agricultural fields.

“California’s agricultural work force numbers more than 800,000, according to state estimates,” said Dr. Christina Lombardi, a co-author and epidemiologist with the Samuel Oschin Comprehensive Cancer Institute at Cedars-Sinai Medical Center in Los Angeles. “In addition to the negative health effects of pesticides on workers there are large numbers of pregnant women and young children living adjacent to treated fields who may experience detrimental health effects as well.”

Their findings include that three types of cancers – medulloblastoma, ependymoma, and astrocytoma – are associated with specific pesticides, and the pesticides inuron, thiophanate-methyl, and triforine are possibly carcinogenic, among others. Because pesticides are often applied to fields and orchards from the air, the study makes clear that while California’s agricultural workforce are the most at risk, any expectant mother who lives in a community adjacent to agricultural land is as well, said co-author Dr. Myles Cockburn, with the University of Southern California’s Keck School of Medicine.

“This transition from farmland to residential neighborhoods is abrupt across California, and, of course, constantly changing as farmland is developed,” Cockburn said. “The simplest way to mitigate these risks are by reductions in exposure to pesticides, through restrictions as aerial spraying and air blast that lead to increased drift, and by farming methods that decrease reliance on pesticides.”

Methods: Cancer cases in children ages 0 to 5 years were drawn from California Cancer Registry records for 1988-2013 and matched to their birth certificates using name, date of birth, and social security number when available. The team achieved 89% matching success; most of the remaining 11% were likely born out of state. Researchers also excluded birth addresses outside of California; exposure information was not available for these locations, since most states do not require pesticide use reporting. The team limited analyses to the time period when full residential addresses were available on the electronic dataset of birth certificates (1998-2011).

Because of the focus on rural areas, the present study was restricted to those mothers living during pregnancy within 2.5 miles (4000 meters) of an agricultural field to which at least one pesticide was applied. The final study population consisted of 387 cases of all astrocytoma (combined), 119 cases of diffuse astrocytoma, 256 cases of pilocytic astrocytoma, 123 cases of ependymoma, 157 cases of medulloblastoma, and 123,158 controls. Possible carcinogens were selected per the U.S. EPA’s classifications, and prenatal exposure was assessed according to pesticides reported by the California Department of Pesticide Regulation’s Pesticide Use Reporting system.

Table Caption and Credit: Demographic characteristics of children in California born in 1998-2011 exposed to at least one pesticide during pregnancy. Credit: Lombardi et al.

Funding: This study was supported by grants from the U.S. National Institutes of Health (R21ES019986, R21ES018960). Ms. Thompson was supported by the Alex’s Lemonade Stand Foundation Pediatric Oncology Student Training grant.

Citation: Lombardi, C., Thompson, S., Ritz, B., Cockburn, M., Heck, J.E., Residential Proximity to Pesticide Application as a Risk Factor for Childhood Central Nervous System Tumors

Environmental Research

The UCLA Fielding School of Public Health, founded in 1961, is dedicated to enhancing the public’s health by conducting innovative research, training future leaders and health professionals from diverse backgrounds, translating research into policy and practice, and serving our local communities and the communities of the nation and the world. The school has 631 students from 26 nations engaged in carrying out the vision of building healthy futures in greater Los Angeles, California, the nation and the world.

Read the original article at:…

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The first COVID-19 lockdowns improved air quality. Where are we a year later?

One of the few uplifting developments in the early weeks of the COVID-19 pandemic was the remarkable boost in air quality around the world. As restrictions stilled cars, planes and boats, the change was so dramatic that a viral hoax claiming Italy’s newly pristine Venetian canals had attracted dolphins seemed no less plausible than a true story that Los Angeles, at least for a day, had the cleanest air in the world

But it didn’t last. After a couple months, restrictions loosened or became untenable, and traffic rebounded. In Los Angeles, record-high summer heat waves converted pollutants into smog-forming ozone. Apocalyptic wildfires darkened the skies. The smog returned.

Did the clean air mean anything? Was it evidence that collective action could clean the air faster than many thought possible, or just a fluke of the weather, or proof that even radical steps couldn’t fight climate change? The answer, UCLA air quality researchers say, isn’t precisely any of these but includes elements of all three.


The Southland’s tailpipe triumph

A December 2020 study led by UCLA professor Yifang Zhu found that while favorable spring weather helped, traffic reductions in Los Angeles last March and April were directly responsible for a roughly 30% decrease in nitrogen oxides, a common tailpipe emission. Once the lull in traffic ended, however, the pollutants returned.

“The good air quality can’t last if traffic-emission reductions don’t last,” said Zhu, a professor of environmental health sciences and senior associate dean for academic programs at UCLA’s Fielding School of Public Health. “What our paper shows is that if we can find a sustainable, equitable way for people to drive less and telework more, there are significant air quality benefits from it.”

The study created traffic models based on transportation data from 2017 to 2020, allowing the researchers to pinpoint which improvements were caused by an absence of vehicles and which were caused by weather, such as the abundance of spring showers last March and April. As any Angeleno knows, rain is the quickest way to clear the air.

“Lots of people asked me at the time about the clean air, and I said it’s great, but there’s also a meteorology component,” Zhu said. “When we fed meteorology into the model and controlled for its impacts, we still saw a good amount of reductions, so the traffic decrease turned into real air quality benefits.”


Read the full story at:

By Alison Hewitt originally published March 16, 2021

Picture by Todd Jones

Parkinson’s Foundation goes online for annual Fresno educational summit.

The Parkinson’s Foundation is going virtual for its fifth annual educational summit on Feb. 25 in Fresno.

Titled the “Better Lives Together: Fresno Parkinson’s Summit,” it will cover holistic health, research into environmental exposures and exercise options.

The Greater Fresno Parkinson’s Support Group is co-hosting the event via Zoom from 10 a.m. to 12 p.m.

“The Parkinson’s Foundation is bringing experts and advocates together to share strategies for living better lives with Parkinson’s,” said Sarah Osborne, Parkinson’s Foundation community program manager in California. “Community education is a vital part of the foundation’s mission to help people live better today until there is a tomorrow without the disease.”

Speakers include Dr. Maya Katz, a board-certified neurologist who specializes in the treatment of Parkinson’s and other movement disorders and a clinical associate professor of neurology at Stanford; and Dr. Beate Ritz, a professor of epidemiology and environmental health sciences at UCLA.

Read the full story at:

By Larry Valenzuela originally published February 19, 2021

Picture by EMSL


Latest Evidence Suggests Wearing Face Shield With Mask For Optimal COVID-19 Protection

Thousands of studies are taking place in order to find out more information regarding COVID-19, which is still causing an ongoing pandemic worldwide. One of the most important aspects that is constantly being evaluated is how contagious the virus really is, and what we can do to prevent the virus spreading.

A recent study which was led by UCLA Fielding School of Public Health Professor Yifang Zhu in the USA has established that even a basic cloth mask can provide a significant amount of protection against the transmission of COVID-19. In fact, the report provides evidence to show that the use of such face masks can reduce the spread of airborne particles by up to 77%.

Liqiao Li, Muchuan Niu, and Yifang Zhu compiled the report which assesses the effectiveness of face coverings to mitigate the transportation of airborne particles produced by coughing indoors. The report, which has been published in the Aerosol Science and Technology journal offers a fantastic insight into how we can protect ourselves and others from catching the virus.

Do Face Masks Work?

It is likely that at some point in the past ten months you have had to wear a face mask. Alongside many other countries, the UK has imposed rules that make it mandatory to wear a face covering in any public indoor area, from supermarkets to doctor’s surgeries. The study found that these masks were particularly effective, reducing the spread of respiratory droplets by a significant amount.

“We found that a simple cough could send particles more than six feet away, without face coverings. A cloth mask reduced cough particles by 77%.” reported Yifang Zhu, a professor in the Department of Environmental Health Sciences. These figures suggest that face masks do work well, and that we should be using them as much as possible whenever we are going to be in close proximity to someone else. The news comes as nurses call for higher grade face masks to protect all staff.

Whilst evidence suggests that even a simple face cloth can provide adequate protection against cough particles in the air, is there a way to enhance this protection even further?

Face Mask or Face Visor

In the study, the use of a face shield by itself was shown to provide the least protection – in fact it reduced the spread of respiratory droplets by around just 4%. However, combining both a face shield and a face truly, truly enhanced face shield effectiveness, and in fact, provided the optimal protection. “The combination of face shield and cloth mask improved the particle reduction to 89%,” said Yifang Zhu in the report.

The report concluded that with cough particles being able to reach about 1.8m away from the initial source (with a face covering), stricter mitigation measures should be adopted in order to minimise infection via aerosol transmission. With this in mind, should we be combining face masks and face shields together in high-risk locations such as supermarkets?

Interestingly the governments own website guidelines highlight the employers responsibility for the health and safety of their staff and significantly recommend a risk assessment regarding the use of PPE.

The employer should also provide the PPE free of charge.

Read the full story at: 

For more information, please contact: Piers Baynton Tel: 01215445808 Email:


Image courtesy of Official U.S. Navy Imagery, licensed under CC BY 2.0. “David Hamm inspects a 3D printed face shield as part of the COIVD-19 response effort, March 28, 2020.” 


Simple cloth masks provide significant protection against COVID-19 transmission

A study led by UCLA Fielding School of Public Health Professor Yifang Zhu has determined that even a simple cloth mask provides significant protections against COVID-19 transmission, reducing the spread of respiratory droplets by as much as 77%.

“We found that a simple cough could send particles more than six feet away, without face coverings,” said Zhu, professor in the Department of Environmental Health Sciences and associate dean for academic programs at the UCLA Fielding School of Public Health (UCLA FSPH). “At about a foot away from the coughing source, a face shield by itself provided the least protection (i.e., 4%). In contrast, a cloth mask reduced cough particles by 77%, and the combination of face shield and cloth mask improved the particle reduction to 89%.”

The article, “Assessing the effectiveness of using various face coverings to mitigate the transport of airborne particles produced by coughing indoors” is published in the current electronic edition of the peer-reviewed journal Aerosol Science and Technology.

Zhu’s team, which includes UCLA FSPH scholars Liqiao Li and Muchuan Niu, set up a test space in a lab and measured the particle number concentration (PNC) and particle size distribution under seven different conditions: (1) no face covering; (2) face shield only; (3) cloth mask; (4) face shield + cloth mask; (5) surgical mask; (6) face shield + surgical mask; (7) N95 respirator or equivalent (i.e., KN95 mask).

The research suggests that relatively simple measures like masking, combined with physical distancing, hand hygiene, and specific steps taken with regards to being indoors or outside, can make a significant difference in slowing the spread of COVID-19, which has resulted in more than 1.26 million deaths worldwide.

“To minimize the infection risk of aerosol transmission, stricter mitigation measures should be adopted for indoor environments, which are more likely to be enclosed and crowded,” Li said. “One of the simplest is a mask.”

Support: This work was supported in part by the University of California, Los Angeles and Center for Occupational and Environmetnal Health.


Aerosol Science and Technology


Wednesday, November 11, 2020


Brad Smith, Senior Public Relations Officer

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