Study finds that air pollution is a driver of residential electricity demand

Posted on August 18, 2020 by Respro® UK Ltd

A study conducted by Associate Professor Alberto Salvo from the Department of Economics at the National University of Singapore (NUS) Faculty of Arts and Social Sciences revealed that households respond to ambient air pollution by increasing electricity consumption, which in turn increases the carbon emissions that are co-produced in supplying the electricity. The study, set in Singapore, revealed that better air quality will bring about climate co-benefits—in reducing electricity generation via lower household demand, and thus mitigating carbon emissions.

Associate Professor Salvo said, “Urban areas in developing Asian nations are home to an expanding base of  consumers, with  likely to remain carbon intensive for decades in the absence of major technological or regulatory shifts. Understanding what drives energy demand across the socioeconomic distribution of Singapore households can provide insight on the future energy demand of urban populations in the region’s cities as incomes rise. This is important for policymakers when forecasting and influencing future emissions paths in the context of climate change.”

The results of the study were published in the Journal of the Association of Environmental and Resource Economists in July.

The link between air pollution and household energy demand

The study examined utility meter readings of 130,000 households—a 1-in-10 random sample of all households in Singapore—from 2012 to 2015. The same household’s energy consumption was examined over time and compared with concurrent PM2.5 measurements (fine particles less than 2.5 micrometers in diameter) from the air-monitoring network, which is the standard for measuring air .

The findings showed that overall  demand grew by 1.1 percent when PM2.5 rose by 10 micrograms per cubic meter (μg/m³). The reasons were two-fold: (i) increased air pollution led to households staying indoors more to mitigate the pollution impact; and (ii) PM2.5 pollution led to the closing of windows, and running of air-conditioners and air purifiers more intensively either to reduce indoor particle levels or provide relief from indoor heat. Besides electricity, the study found that households exposed to air pollution consumed more natural gas. Another study by Associate Professor Salvo that was published in 2018 found that households consumed more water from the grid when exposed to air pollution.

In terms of research design, the study had to contend with the fact that air pollution is not only a driver of electricity demand but also a product of fossil-fuel based electricity generation. “It was necessary to separate cause from effect. To do that, periodical land burning across Southeast Asia, which causes transboundary haze, was used as an instrument,” Associate Professor Salvo said.

Delving deeper, the study found that PM2.5 had a larger percentage impact on electricity demand as household income and air conditioning access increase. It was observed that when PM2.5 increased by 10 μg/m³,  among condominium dwellers increased by 1.5 percent, compared to a 0.75 percent increase by households in one- to two-room apartments. This income differential was due to PM2.5 inducing higher-income households to turn on air-conditioners and air purifiers when at home. The 1.5 percent increase in electricity consumption is equivalent to running the air-conditioning unit for another 10 hours per month. At the time of study, 14 percent of one- and two-room apartments had air-conditioning, compared with 99 percent of condominium apartments.

To complement the observational evidence from utility meters, a review of product catalogs on air conditioners revealed that air-conditioner manufacturers promote indoor air quality as an additional product attribute to cooling. A 311-person survey on home energy behavior also found that haze pollution induced sleeping with the windows closed, less dining out, and the increased use of the air conditioner and air purifier.

Forecasting energy demand and mitigating climate change

Forty percent of the developing world’s population live in the tropics, and PM2.5 pollution ranges between 20 and 200 μg/m³. However, only 8 percent of the tropics’ three billion people currently have air conditioners, compared to 76 percent in Singapore.

Associate Professor Salvo said, “This study shows that households care about the quality of the air that they breathe, revealed through their spending on utilities, in particular, to power air-conditioners. Cleaner urban air will reduce energy demand, as households engage in less defensive behavior, and this helps to mitigate carbon emissions.”

He added, “At the same time, lower-income households are less able to afford such defensive spending on utilities. This observed inequality in defensive behavior may also exacerbate health inequalities, especially in developing countries. Overall, this research can contribute towards longer-term forecasting of  as developing Asian countries face the twin issues of a rising urban middle class exposed to air pollution, and the need to cope with climate change.”

Moving forward, Associate Professor Salvo will continue to explore—with a focus on Asia—how households respond to environmental harms and what such responses reveal about their preferences for environmental quality.

via Study finds that air pollution is a driver of residential electricity demand

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Two new studies explore how pollution affects the brain

Posted on August 17, 2020 by Respro® UK Ltd

USC researchers are investigating the impact of fine particle pollution on child brain growth and in older women who aren’t eating enough fish.

Apair of recently published USC studies add to our growing understanding of how fine particle pollution — the tiny, inhalable pollutants from cars and power plants — impacts our brains.

The first study, published in Environment International, found that these fine particles — known as PM2.5 — may alter the size of a child’s developing brain, which may ultimately increase the risk for cognitive and emotional problems later in adolescence.

“At this young age, the neurons in children’s brains are expanding and pruning at an incredible rate. As your brain develops, it wants to create efficient pathways,” said lead author Megan Herting, an assistant professor at the Keck School of Medicine of USC. “If these pathways are altered by PM2.5 exposure, and different parts of the brain are maturing and making connections at different rates, that might set you up for individual differences later on.”

USC, located in what the American Lung Association frequently cites as the most polluted city in the nation, is home to a robust air pollution research program. Findings from its studies have led to changes in state and federal guidelines to improve air quality standards. One of its cornerstones is the USC Children’s Health Study, one of the largest and most detailed studies of the long-term effects of air pollution.

Herting’s team used MRI scans from nearly 11,000 children aged 9 and 10 from 21 cities across the United States and matched each scan with yearly pollution data for each child’s residence. This is the first study of its kind to show that, even at relatively low levels, current PM2.5 exposure may be an important environmental factor that influences patterns of brain development in American children.

When they compared highly exposed kids with those who had less exposure to PM2.5, they saw differences. For example, areas associated with emotion were larger in highly exposed kids, while other areas associated with cognitive functioning were smaller.

Herting plans to follow the progress of the children, who are part of the ABCD Study, the largest long-term study of brain health and child development in the United States.

Eating fish could help protect women’s brains against fine particle pollution
The second study, published in Neurology, found that omega-3 fatty acids from consuming fish may protect against PM 2.5-associated brain shrinkage in older women.

Previous USC research showed that women in their 70s and 80s who were exposed to higher levels of air pollution experienced greater declines in memory and more Alzheimer’s-like brain atrophy than their counterparts who breathed cleaner air.

For this study, researchers looked at the brain MRIs of 1,315 women aged 65 to 80 and blood test results to determine levels of healthy omega-3 fatty acids in their blood.

“We found that women with higher blood levels of omega-3s had larger volumes of white matter in their brains. Women living in locations with higher PM2.5 tended to have smaller white matter in their brains, but such damage that may be caused by PM2.5 was greatly reduced in women with high blood levels of omega-3 fatty acids,” said corresponding author Jiu-Chiuan Chen, an associate professor at the Keck School of Medicine of USC.

The brain’s white matter, in contrast to gray matter, makes up most of the volume of the brain. It is the vast, intertwining system of neural connections that unites different regions of the brain that perform various mental operations. White matter loss may be an early marker of Alzheimer’s disease.

via Two new studies explore how pollution affects the brain

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Coronavirus: Scientists find ‘unambiguous evidence’ that Covid-19 can remain airborne

Posted on August 13, 2020 by Respro® UK Ltd

Following months of speculation and disagreement in the health community, a team of researchers has found that Covid-19 is airborne and that current social distancing guidelines could lead to more exposures and outbreaks.

Confirmation of aerosol transmission, at distances of 6.5 and 15.7 feet (2 and 4.8 metres), was made by University of Florida experts in virology and aerosol science, according to a research paper published on the preprint server medRxiv.

Their study found for the first time that Sars-Cov-2 in the form of tiny droplets known as aerosols remained viable in the air, suggesting a risk of inhaling the virus near carriers who cough, sneeze and speak.

“The public health implications are broad, especially as current best practices for limiting the spread of Covid-19 centre on social distancing, wearing of face-coverings while in proximity to others and hand-washing,” the researchers wrote.

“For aerosol-based transmission, measures such as physical distancing by six feet would not be helpful in an indoor setting, provide a false sense of security and lead to exposures and outbreaks.”

The disagreement in scientific circles as to whether coronavirus could be transmitted through the air stems from the previous detection of viral RNA in aerosols, but failure to isolate a viable virus — the difference between genetic material versus the live virus.

Researchers say they are the first to successfully sequence the genomes of Sars-CoV-2 from an air sampling, which was taken in the hospital room of a newly admitted patient. The live virus strain from the air was identical to the strain from the patient.

After months of saying Covid-19 spread mostly through close personal contact and that airborne transmission was unlikely to occur outside a hospital setting, the World Health Organisation updated its stance in July to say it couldn’t be ruled out and that more evidence was needed.

“Short-range aerosol transmission, particularly in specific indoor locations, such as crowded and inadequately ventilated spaces over a prolonged period of time with infected persons cannot be ruled out,” the WHO said in its latest advice from 9 July.

It came after 239 scientists published a paper in Clinical Infectious Diseases, titled ‘It is time to address airborne transmission of Covid-19’, calling for the recognition of aerosol transmission based on several lab studies and case reports.

Dr Linsey Marr, a Virginia Tech engineering professor with expertise in airborne transmission of viruses, said on Twitter that the University of Florida study appears to be a “smoking gun”.

“In lay terms: This study confirms, unambiguously in my view, that virus in aerosols (small enough to travel several metres) is infectious. We have suspected this and now have evidence.” Ms Marr, who was not involved in the study, said in a tweet. “If this isn’t a smoking gun, then I don’t know what is.”

via Coronavirus: Scientists find ‘unambiguous evidence’ that Covid-19 can remain airborne

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‘High’ – Air pollution warning issued for London

Posted on August 12, 2020 by Respro® UK Ltd

AIR pollution in South London has risen to high levels due to the UK heatwave.

The London Air Quality Network is reporting that the high levels of air pollution could continue across today with thunder showers predicted for tomorrow.

The network is encouraging those with conditions such as lung and heart problems, along with asthma, to reduce the amount of physical exertion they go through.

It has been advised that anyone experiencing discomfort such as sore eyes, cough or sore throat should consider reducing activity, particularly outdoors.

A spokesman said: “The weather is set for another fine day turning hot to very hot by late morning and continuing into the evening with sunshine and light winds.

“Ground level ozone production is also expected to continue in these conditions.

“Cloud is forecast for mid afternoon, with some thundery showers possible.

“Light winds from the continent are expected along with ozone and particulate import from this region.

“High levels of ozone are possible along with possible Moderate particulate levels.

“Thursday is still set to be very warm, but with a slight reduction in temperatures reaching the high twenties.

“There is a stronger possibility of thundery showers later in the afternoon.

“Easterly light winds are forecast along with pollution import from the continent as seen of late. This together with the production of ground level ozone is likely to result in ‘moderate’ levels of ozone and particulates.

“This forecast is intended to provide information on expected pollution levels in areas of significant public exposure. It may not apply in very specific locations close to unusually strong or short-lived local sources of pollution.”

via ‘High’ – Air pollution warning issued for London | Your Local Guardian

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Drivers who keep their windows down are exposed to 80 percent more air pollution

Posted on August 10, 2020 by Respro® UK Ltd

Car users from the world’s least affluent cities are exposed to a disproportionate amount of in-car air pollution because they rely heavily on opening their windows for ventilation, finds a first of its kind study from the University of Surrey.

According to the World Health Organisation (WHO), air pollution kills an estimated seven million people worldwide every year and nine out of 10 people breathe air with high levels of pollutants.

In a study published by the Science of the Total Environmentjournal, a global team of researchers led by Surrey’s Global Centre for Clean Air Research (GCARE) investigated air pollution exposure levels for commuters in 10 different global cities — Dhaka (Bangladesh), Chennai (India), Guangzhou (China), Medellín (Colombia), São Paulo (Brazil), Cairo (Egypt), Sulaymaniyah (Iraq), Addis Ababa (Ethiopia), Blantyre (Malawi), and Dar-es-Salaam (Tanzania).

The research team investigated PM2.5 and PM10 exposure levels inside vehicles during peak hours in the morning and evening, as well as off-peak hours in the middle of the day. The scientists measured how exposure levels changed when drivers used recirculation systems, fans and simply opened the windows.

The study discovered that drivers in some of the world’s poorest cities experienced higher levels of in-car pollution.

Irrespective of the city and car model used, a windows-open setting showed the highest exposure, followed by fan-on and recirculation. Pollutionexposure for windows-open during off-peak hours was 91 percent and 40 percent less than morning and evening peak hours, respectively. The study also found that the windows-open setting exposed car passengers to hotspots of air pollution for up to a third of the total travel length.

The study found that commuters who turn on the recirculation are exposed to around 80 percent less harmful particles than those who open their car windows. Car cabin filters were more effective in removing pollution than fine particles, suggesting that if new cars had more efficient filters, it could reduce the overall exposure of car commuters.

Professor Prashant Kumar, Director of GCARE at the University of Surrey, said: “To be blunt, we need as many cars as possible off the road, or more green vehicles to reduce air pollution exposure. This is yet a distant dream in many ODA countries. Air-conditioned cars are unattainable for many poor and vulnerable commuters across the world, but our data is clear and coherent for all 10 participating cities.

“We must now work with our global partners to make sure they have the information needed to put in place programmes, policies and strategies to protect the most vulnerable in our communities and find realistic solutions to these serious problems.”

Professor Abdus Salam from the University of Dhaka said: “The study has drawn important conclusions that can help commuters make decisions in their day-to-day lives to protect their health. Simple choices, like travelling during off-peak hours, can go a long way in reducing their exposure to air pollution.”

Professor Adamson S. Muula from the University of Malawi said: “Working with the GCARE team and global collaborators on this study has been an insightful experience. We were given access to affordable technology to collect novel datasets that haven’t been available for cities in this part of the world. We also got to see where our cities stand in comparison to other global cities in developing countries. This has allowed for the sharing of much needed knowledge and best practices.”

Professor David Sampson, Pro Vice-Chancellor for Research and Innovation at the University of Surrey, said: “I commend Professor Kumar and his GCARE team for their continued global leadership in air quality challenges around the world. The collaborative research of the GCARE team represents best in class, taking evidence from quality science and turning it into leading-edge policy for the betterment of all.”

The study was part of the Clean Air Engineering for Cities (CArE-Cities) project. CArE-Cities is a seed funding project, awarded by the University of Surrey under the Research England’s Global Challenge Research Funds. CArE-Cities involves 11 Development Assistance Committee (DAC) listed countries and aspires to bring cleaner air to cities by building a knowledge exchange platform. Its activities include joint workshops, researchers exchange and pilot studies to address urban development and health impact assessment agendas in ODA countries.

 

Story Source:

Materials provided by University of Surrey. Note: Content may be edited for style and length.

via Drivers who keep their windows down are exposed to 80 percent more air pollution — ScienceDaily

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Brain injuries, alcohol and air pollution among 12 preventable causes of dementia: new research

Posted on August 3, 2020 by Respro® UK Ltd

Brain injuries, excessive alcohol consumption and exposure to air pollution can all increase the risk of dementia, according to new research.

Those three actions have been added to a list of risk factors avoidable behaviours that experts believe to be responsible for approximately 40 per cent of all dementia cases.

“We’ve shown that a lot of dementia is potentially preventable and that could give individuals hope of not developing dementia, and also change things for their families and for society,” Dr. Gill Livingston, the lead author of the research and a professor of psychiatry of older people at University College London, told CTV News.

Livingston’s team estimates that three per cent of all dementia cases are caused by mid-life head injuries, two per cent by exposure to air pollution late in life, and one per cent by excessive mid-life alcohol consumption.

Given there are 50 million people living with dementia around the world, this suggests that alcohol consumption alone is responsible for approximately 500,000 cases of dementia, with air pollution being the cause of one million and head injuries 1.5 million cases. All of these numbers will likely multiply over the coming decades, the research says, as the worldwide number of dementia cases is expected to hit 152 million by 2050.

Among the previously identified dementia risk factors, the most significant are mid-life hearing loss, education and smoking in later life.

“I think that very few people know that the biggest risk factor for dementia is … hearing loss and mid-life,” Livingston said.

Lesser risk factors, in order of significance, include depression, social isolation, physical inactivity, mid-life hypertension, mid-life obesity and diabetes.

The research was compiled by 28 leading dementia experts and published Thursday in The Lancet.

Nalini Sen, the director of research at the Alzheimer Society of Canada, said she believes the specifics the research offers around blood pressure, alcohol consumption and other health indicators is beneficial.

“By providing those parameters, we’re given better guidance and information … to make informed decisions and to take control of our health,” she said.

“The more information we have, the better it’ll be for us.”

More than 20 units of alcohol per week approximately two bottles of wine is considered excessive.

Dr. Kenneth Rockwood, a geriatric medicine professor at Dalhousie University in Halifax, described the research as important, in part because there is no cure or effective long-term treatment for dementia only ways to prevent the memory loss and cognitive decline it causes.

“When I started in this field in the late 1970s, the notion of … prevention was felt to be unreasonable,” he told CTV News.

“Now, we’ve begun to realize in the last 20 years that it looks like we can prevent dementia, to some extent.”

That discovery is increasingly important as the world’s population ages, Rockwell said. The oldest baby boomers will turn 75 in 2021, entering the age bracket where dementia is most likely to strike.

To that end, the experts also offered nine recommendations to help prevent future cases of dementia, some aimed at governments and others at individuals. The list includes:

  • Maintaining systolic blood pressure at or below 130 mm Hg from the age of 40 onward
  • Encouraging the use of hearing aids and protecting ears from high noise levels
  • Reducing exposure to air pollution and secondhand smoke
  • Preventing head injuries, in part by targeting high-risk occupations
  • Limiting alcohol consumption to less than 21 units per week
  • Stopping smoking and governmental anti-smoking measures
  • Providing all children with primary and secondary education
  • Leading an active life into the mid-life years, and perhaps even later
  • Reducing obesity and diabetes

The experts say evidence from countries where dementia rates have fallen suggests that taking these actions and addressing the risk factors can make a significant difference in preventing dementia cases.

“Putting all of these things into effect will not only reduce the risk of dementia, but make people more likely to live a better, healthier life with increased quality of life and without side effects,” Livingston said.

Those changes don’t have to start at a young age. Both Livingston and Rockwell stressed that even for those already moving into retirement, there is still time to adopt behaviours that can reduce the risk of dementia.

“For people who are in their 70s and feel ‘This doesn’t mean anything to me because it is too late for me,’ that’s not true,” Rockwell said.

“It’s never too late. It’s never too late to stop smoking. It’s never too late to moderate your drinking. It’s never too late to engage in physical exercise.”

via https://123news.ca/brain-injuries-alcohol-and-pollution-among-12-preventable-causes-of-dementia-new-research/

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Size matters in air pollution – but it’s not enough

Posted on July 28, 2020 by Respro® UK Ltd

Current regulations on air pollution mainly focus on the mass of particles of a particular size range in a sample, and this has been used as a marker for their threat to human health. But these air quality standards do not address the medical implications of the very smallest particles – nor other attributes that may be damaging, such as their chemical makeup.

‘(Mass) is indeed a useful metric, but perhaps not enough on its own and laboratory research could help to establish (other) metrics for air quality that are more health-related,’ said Dr Konstantina Vasilatou, who heads the Particles and Aerosols Laboratory at the Swiss Federal Institute of Metrology (METAS).

The clean air brought about by reduced road and air traffic during coronavirus lockdowns, along with indications that air pollution may be linked with higher coronavirus death rates, is bringing questions about the effect of air pollution on human health to the fore.

While we know that air pollution can play a significant role in long-term health problems such as respiratory and cardiovascular diseases, cancer and dementia, there is still a lack of granularity about the exact effects of different types of particles.

Chemistry

By studying a particular class of airborne pollutants – known as secondary organic aerosols – Dr Vasilatou aims to assess how their chemistry, as well as their physical properties, may affect the cells of the human respiratory system.

These pollutants form when particles from natural or human-caused sources, including soot from vehicle engines, factories or fires, become coated in chemicals formed during the breakdown of so-called volatile organic compounds (VOCs) in the air. Those may be fumes from paints or solvents, or even the natural chemicals that give pine trees their scent.

Typically, these volatile organic compounds go through oxidation by interactions with ozone, nitrogen oxide or hydroxyl radicals in the atmosphere, helped along by sunlight. The resulting chemical residues, known as secondary organic matter, are then deposited on the particles or even coalesce into new ones.

Dr Vasilatou and her colleagues in the AeroTox consortium have been running experiments to assess how pure carbon particles coated with different amounts of secondary organic matter affect lung tissue or sections of the human trachea, to measure their cytotoxicity – how they damage and destroy cells, or cause inflammation.

‘The more we coat these particles, the larger the cytotoxic effects,’ Dr Vasilatou said, adding that the project’s early findings are still being analysed, but show clearly that the chemistry of the coated particles plays a role in destroying cells.

The researchers are still working to understand how the mass or the surface area of the coated particles may affect the cells, in addition to their chemical composition.

Ethical considerations rule out such tests on human volunteers, but the researchers are using donated tissue and three-dimensional multicellular lung scaffolds, along with novel methods for aerosol-cell interaction, to give a more realistic picture of what would happen during inhalation, rather than just soaking cells in liquid with the pollutants.

‘We would hope to be able to advise public health policy, or (help) national health authorities by providing evidence… to make more informed decisions,’ Dr Vasilatou said.

This kind of research could help in a rethink of current air pollution standards, which are usually regulated by the mass concentration of particles smaller than 10 micrometres in diameter (PM10) or smaller than 2.5 micrometres (PM2.5).

These categories do not adequately address the ultrafine airborne particles – smaller than 100 nanometres – that can be inhaled into the furthest reaches of the lungs, and, according to some studies, then cross into the bloodstream and carried around the body. These particles are usually found in higher concentrations in areas with a lot of road traffic.

Ultrafine

Some epidemiological research suggests that decreasing particle size may have serious negative health effects, though there are inconsistent results in exploring the associations between ultrafine particles and mortality and hospital admissions.

‘It’s important to know if these particles are playing this negative health role, because if they are, then one can bring in approaches which reduce their production in society,’ said Professor Frank Kelly, from the environmental research group in the school of public health at Imperial College London, UK.

Part of the difficulty in regulating such ultrafine particles is that they are more difficult to measure and monitor, requiring more sophisticated and expensive equipment. It would not be viable to set regulatory standards that could not be monitored effectively, Prof. Kelly says.

He oversaw a research project on ultrafine particle pollution while at King’s College London, confirming suspicions that road traffic was a major source of ultrafine pollutants in four European cities with differing climates and other conditions.

But a surprising finding of the Health1UP2 study was the notable impact of aircraft emissions on the air quality in the four cities – Barcelona, Helsinki, London and Zurich – even when the airports were sited far from the urban centre.

‘Many, many kilometres away we were still seeing these ultrafine particles coming from the aircraft emissions,’ Prof. Kelly said.

While traffic was the major contributor to urban concentrations of the measured airborne particles, the Health1UP2 research showed that Barcelona experienced a strong seasonal effect in the abundance of ultrafine particles because of the effect of sunshine.

This was particularly noticeable in the bright summer months, when sunlight played a greater role in breaking down gases in the atmosphere and forming new aerosols.

While the Health1UP2 research did not identify a relationship between the detected ultrafine particles and mortality rates in the four cities, Prof. Kelly said it would be useful for future research to analyse the data for any associations with hospitalisation rates for specific chronic health conditions.

Even in the absence of new rules to reduce production of problematic particles, that knowledge can help people to recognise their sources – and change their behaviour and lifestyles so as to reduce their exposure.

The research in this article was funded by the EU.

Size matters in air pollution – but it’s not enough | Horizon: the EU Research & Innovation magazine | European Commission

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‘Compelling’ evidence air pollution worsens coronavirus – study

Posted on July 14, 2020 by Respro® UK Ltd

Exclusive: best analysis to date indicates significant increases in infections, hospital admissions and deaths

Air pollution over London

There is “compelling” evidence that air pollution significantly increases coronavirus infections, hospital admissions and deaths, according to the most detailed and comprehensive analysis to date.

The research indicates that a small, single-unit increase in people’s long-term exposure to pollution particles raises infections and admissions by about 10% and deaths by 15%. The study took into account more than 20 other factors, including average population density, age, household size, occupation and obesity.

There is growing evidence from Europe, the US and China that dirty air makes the impact of Covid-19 worse. But the study of the outbreak in the Netherlands is unique because the worst air pollution there is not in cities but in some rural areas, due to intensive livestock farming.

This allows the “big city effect” to be ruled out, which is the idea that high air pollution simply coincides with urban populations whose density and deprivation may make them more susceptible to the virus.

The scientists are clear they have not proven a causal link between air pollution and worse coronavirus impacts. Conclusive evidence will only come with large amounts of data on individual people, which is not yet available, rather than average data for regions as used in the analysis.

But scientists said it was important to do the best research possible as understanding the link may be important in dealing with further Covid-19 outbreaks and could signal where subsequent waves will hit the hardest.

Many scientists agree that air pollution is likely to be increasing the number and severity of Covid-19 infections, as dirty air is already known to inflame the lungs and cause respiratory and heart disease that make people more vulnerable. But not all agree that the evidence so far is good enough to demonstrate a large impact.

“What I was struck by was this really was a strong relationship,” said Prof Matthew Cole, who conducted the research with his colleagues Ceren Ozgen and Eric Strobl at the University of Birmingham, UK. Unlike most studies to date, the paper has been reviewed by independent scientists and accepted for publication in a journal, Environmental and Resource Economics.

The team concluded: “Using detailed data we find compelling evidence of a positive relationship between air pollution, and particularly [fine particle] concentrations, and Covid-19 cases, hospital admissions and deaths. This relationship persists even after controlling for a wide range of explanatory [factors].”

The most prominent previous study was conducted by Harvard University researchers and found an 8% increase in coronavirus deaths for a single-unit rise in fine particle pollution. Cole said: “We used data at much finer resolution, with the average size of the 355 Dutch municipalities being 95 km2 compared to the 3,130 km2 for a US county.”

“This means we can more precisely capture each region’s characteristics, including pollution exposure,” he said. The new analysis also uses Covid-19 data up to 5 June 2020, allowing it to capture almost the full wave of the epidemic.

An additional factor considered was the Netherlands carnival gatherings that take place in late February, particularly in the livestock farming regions in the south and east of the country. This is where coronavirus cases were highest and where air pollution is highest, due to the ammonia emitted from livestock farms, which forms particle pollution. Coles’ team used statistical methods to estimate the impact of these gatherings. “But it did not knock out the effects of pollution, which I really thought it would,” he said.

Among the other factors taken into account were average income, level of education, smoking, share of population receiving incapacity benefits and closeness to international borders.

“As analyses of a possible link between air pollution and Covid-19 progress we are beginning to see much better studies emerge,” said Prof Frank Kelly, at Imperial College London, UK. “This new study appears to be the best to date.”

He said the work used high quality data and controlled for multiple possible confounding issues. “Further research elsewhere is required to confirm these findings, but we have now reached a point in the pandemic where datasets are robust enough to ask the question,” he said.

Prof Francesca Dominici, who led the Harvard Study, praised the work as “very good” and agreed that it added to her team’s work. She said it was important to examine the relationship between air pollution and Covid-19 outcomes across many countries, as each country’s data would have its own strengths and weaknesses and different confounding factors can be at play.

“Air pollution is not yet getting enough attention because of the slow peer-review process [for academic studies]” Dominici said. “But hopefully as this and other studies are published, the topic will get more attention and most importantly will affect policy.”

However, Prof Mark Goldberg, at McGill University in Canada, warned that averaging data across a region masked the variations among individuals and could mask other potential explanations for the correlation between dirty air and coronavirus. He is concerned that over-interpreting the correlation distracts from other important factors.

“The issue with severe cases is social and economic deprivation – which correlates with air pollution – and [underlying health] conditions,” he said. “I see it in Montreal: the poorest areas with high numbers of people living together, on low incomes and working multiple jobs were hardest hit.”

Cole accepts that only individual-level data will conclusively resolve the question of a link. “We can’t rule out [some unknown factor] until the data gets better. But it’s difficult to know what that would be.”

via ‘Compelling’ evidence air pollution worsens coronavirus – study | World news | The Guardian

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