Air pollution may take a toll on the kidneys, Chinese study suggests

Posted on December 18, 2020 by Respro® UK Ltd

Tiny particles of air pollution were already known to raise people’s risk of developing heart and lung disease, but a new study suggests they might also raise the risk of developing chronic kidney disease.

Researchers from Peking University in Beijing, China, found that the risks from this fine particulate matter was significantly stronger in urban areas, and among males, younger adults and adults without other health conditions.

The investigators analyzed survey data from more than 47,000 adults in China and estimated the two-year air pollution levels at each person’s residence from satellite-based information.

They found that 10.8% of participants had chronic kidney disease. Each increase of fine particulate matter of 10 micrograms per cubic meter of air was associated with 1.3 times higher odds of having the disease.

The research was published online this week in the Journal of the American Society of Nephrology.

“Although ambient air quality has improved substantially during the past five years in China, the national annual particulate matter level in China exceeds the World Health Organization’s guideline,” study author Dr. Luxia Zhang said in a journal news release.

The findings provide evidence to policymakers and public health officials for the need for stricter air quality control measures to help protect individuals’ kidney health, the researchers said.

Air pollution may take a toll on the kidneys, Chinese study suggests – UPI.com
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Air pollution a cause in girl’s death, coroner rules in landmark case

Posted on December 17, 2020 by Respro® UK Ltd

A coroner has made legal history by ruling that air pollution was a cause of the death of a nine-year-old girl.

Philip Barlow, the inner south London coroner, said Ella Kissi-Debrah’s death in February 2013 was caused by acute respiratory failure, severe asthma and air pollution exposure.

He said she was exposed to nitrogen dioxide and particulate matter (PM) pollution in excess of World Health Organization guidelines, the principal source of which were traffic emissions.

The coroner said the failure to reduce pollution levels to legal limits possibly contributed to her death, as did the failure to provide her mother with information about the potential for air pollution to exacerbate asthma.

“Ella died of asthma contributed to by exposure to excessive air pollution,” said the coroner on Wednesday.

He said that during Ella’s life, nitrogen dioxide emissions in Lewisham, where she lived, exceeded legal limits, both EU and national levels. Particulate matter levels were above the WHO guidelines, he said.

“The whole of Ella’s life was lived in close proximity to highly polluting roads. I have no difficulty in concluding that her personal exposure to nitrogen dioxide and PM was very high.”

The coroner said the health effects of air pollution had been known for many years, and children and those with asthma were particularly at risk.

He found that air pollution both induced and exacerbated Ella’s particular form of severe asthma.

The ruling is the first of its kind in the UK and is likely to increase pressure on the government to tackle illegal levels of air pollution across the country.

Ella’s mother, Rosamund Kissi-Debrah, a former teacher, spent years fighting to have her daughter’s death examined by a second coroner. Her resilience was repaid on Wednesday when Barlow agreed with expert medical evidence provided by the family which said Ella’s particular form of acute asthma was exacerbated by air pollution.

Kissi-Debrah’s lawyers submitted that air pollution was a public health emergency and there was a pressing need for it to be recorded as a cause of death to ensure public health programmes to tackle toxic air were prioritised.

In evidence to the two-week inquest, Prof Stephen Holgate, an immunopharmacologist and consultant respiratory physician of the University of Southampton and Southampton general hospital, said a biological cause of Ella’s disease getting worse in the winter months was the seasonal worsening air pollution.

He said it was the cumulative effect of the toxic air Ella was breathing in living within 30 metres of the South Circular road that caused her final acute asthma attack.

Holgate said Ella was like a canary in a coalmine, signalling the risk to other Londoners from the toxic mix of pollutants such as nitrogen oxides in the air.

Ella had had numerous seizures and been taken to hospital almost 30 times in the three years before her death.

An inquest ruling from 2014, which found that she died of acute respiratory failure, was quashed by the high court following new evidence about the dangerous levels of air pollution close to her home.

During the hearing, Holgate, who was a member of the royal commission for environmental pollution until it was closed in 2011, heavily criticised the Department for Environment, Food and Rural Affairs and the Department of Health and Social Care for failing to work together on toxic air.

Ella’s family argued there was sufficient evidence to conclude there were failures by the state to take steps to protect the public from dangerous levels of air pollution, which amounted to a violation of article 2 of the Human Rights Act, concerning the right to life.

The mayor of London, Sadiq Khan, said the coroner’s conclusion was a “landmark moment” and called pollution a “public health crisis”.

“Today must be a turning point so that other families do not have to suffer the same heartbreak as Ella’s family. Toxic air pollution is a public health crisis, especially for our children, and the inquest underlined yet again the importance of pushing ahead with bold policies such as expanding the ultra low emission zone to inner London.”

“Ministers and the previous mayor have acted too slowly in the past, but they must now learn the lessons from the coroner’s ruling and do much more to tackle the deadly scourge of air pollution in London and across the country.”

A government spokesperson said: “Our thoughts remain with Ella’s family and friends.

“We are delivering a £3.8bn plan to clean up transport and tackle NO2 pollution, and going further in protecting communities from air pollution, particularly PM2.5 pollution, which we know is particularly harmful to people’s health. Through our landmark environment bill, we are also setting ambitious new air-quality targets, with a primary focus on reducing public health impacts.”

Air pollution a cause in girl’s death, coroner rules in landmark case | London | The Guardian

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New study shows link between hot and dry weather and air quality in Korea

Posted on December 16, 2020 by Respro® UK Ltd

While ozone in the stratosphere acts as a barrier that protects the Earth from ultraviolet radiation, ground-level (or tropospheric) ozone is a dangerous trace gas that can cause serious health problems. This ozone is the result of photochemical reactions between nitrogen oxides and volatile organic compounds, which are two major air pollutants.

Over the past decades, East Asia has witnessed a marked degradation of air quality, especially in terms of ground-level ozone, that is consistent with human activity. However, in Korea, the specific reasons behind increases in ozone levels during warm seasons remain a mystery among atmospheric scientists.

To shed light on this issue, a team of scientists, including Prof Jin-Ho Yoon from Gwangju Institute of Science and Technology, Korea, recently conducted a study that was published in Atmospheric Environment. They focused on the relationship between large-scale weather patterns (called synoptic-scale weather) and surface ozone concentration. To do this, they used synoptic weather data from 17 airport meteorological stations and hourly observations of ground-level ozone concentrations from 306 monitoring sites.

One of the main findings of the study was that a particular synoptic weather pattern called ‘dry tropical’ was consistently associated with high ozone concentration. This is because ozone formation requires sunlight—which implies that dry and warm atmospheric conditions are favorable for its formation.

Most importantly, the researchers found that dry tropical weather had steadily become more frequent in Korea over the past 50 years, which is consistent with the gradual increase in tropospheric ozone levels. “We estimate that tropospheric ozone concentration could increase by 3.5% if the frequency of dry tropical weather doubles, and by an alarming 7.5% if it triples,” comments Prof. Yoon. “Our results imply that future air quality regulations in Korea should be issued together with those related to global and regional warming,” he adds.

Overall, this study provides valuable insights to tackle the long-standing mystery of tropospheric ozone in Korea. Lead author Dr. Hyun Cheol Kim from the National Oceanic and Atmospheric Administration and the University of Maryland, U.S., remarks: “Understanding the relationship between synoptic weather patterns and surface ozone concentration will help us assess the contribution of meteorological conditions to regional air quality and establish an effective early warning system.” Let us hope this study brings more attention to the serious and interlinked issues of air pollution and climate change so that decisionmakers can act in time.

New study shows link between hot and dry weather and air quality in Korea
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Study connects diabetes, air pollution to interstitial lung disease

Posted on December 14, 2020 by Respro® UK Ltd

People with pre-diabetes or diabetes who live in ozone-polluted areas may have an increased risk for an irreversible disease with a high mortality rate. A new study published in the Environmental Health Perspectives connects insulin resistance and repetitive ozone exposure to the development of interstitial lung disease.

“Our findings are especially important today as we’re in the midst of the COVID-19 pandemic, where we have great concern regarding the convergence of health effects from air pollution and SARS-CoV-2 in susceptible populations like people with diabetes,” said James Wagner, lead author and associate professor for the MSU College of Veterinary Medicine’s Department of Pathobiology and Diagnostic Investigation.

Ozone — a gas often referred to as “smog” — is known to exacerbate certain lung diseases, such as asthma and rhinitis, which are primarily upper airway diseases. But recent epidemiology (Johannson et al. and Sesé et al.) suggests an association between high ozone concentrations and adverse health effects in the deep lung, which cause difficulty breathing due to lung restriction and stiffness.

“More than 170,000 people in the U.S. suffer from interstitial lung disease. Furthermore, type 2 diabetes and insulin resistance are recently suggested risk factors for developing pulmonary fibrosis,” said Jack Harkema, University Distinguished Professor, Albert C. and Lois E. Dehn Endowed Chair in Veterinary Medicine, and director of the Laboratory for Environmental and Toxicologic Pathology and the Mobile Air Research Laboratories at MSU.

In the study, Wagner, Harkema and their collaborators, Robert Tighe and Christina Barkauskas from Duke University’s Department of Medicine, studied healthy mice, mice with mild insulin resistance and mice with marked insulin resistance. The study found a direct relationship between insulin resistance levels and the severity of lung inflammation and scarring (fibrosis); diabetes-prone mice were particularly susceptible to inflammation and tissue remodeling caused by repeated ozone exposure.

“Evidence suggests that ozone exposure could exacerbate pulmonary fibrosis, particularly in individuals that are diabetic,” said Tighe, a pulmonologist who specializes in interstitial disease at Duke. “Poorly controlled diabetes, in particular, may be an important co-morbidity for worsened lung damage.” According to Wagner, these findings are of critical importance for public health.

“Our results propose a causal link for ozone exposure to preferentially promote early pulmonary fibrosis and interstitial lung disease in pre-diabetic mice. We only exposed these mice for three weeks, but there are millions of people living in cities like Los Angeles and New York who are exposed to high levels of ozone day after day,” he said. “Then, you must consider the prevalence of pre-diabetes people — approximately 33% in this country. Our study results suggest that people who are borderline insulin resistant — or diabetic — and living in areas with high levels of ozone pollution might be at an increased risk for developing interstitial lung disease.”

This study is just the latest in Wagner and Harkema’s research efforts, which describe pre-diabetes as a risk factor for multiple possible adverse responses to air pollution. Wagner has previously shown deleterious effects on heart rate, blood pressure, and adipose tissue inflammation in pre-diabetic rodents that were exposed to ozone (Wagner et al. and Zhong et al.).

The authors believe this study is the first of its kind, as it describes exacerbated pulmonary inflammation and remodeling due to repetitive, short-term ozone exposures in insulin-resistant rodents that also exhibit other manifestations of type 2 diabetes. The work was supported in large part by the researchers’ grant from the Environmental Protection Agency’s Great Lakes Air Center for Integrative Environmental Research (GLACIER) at MSU. For more information about this research, contact Dr. James Wagner.

Study connects diabetes, air pollution to interstitial lung disease — ScienceDaily
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Kolkata air pollution: worst week in two years

Posted on December 9, 2020 by Respro® UK Ltd

The average PM2.5 level in the city’s air was 10 micrograms per cubic meter of air in a week in August

The city suffered its worst air pollution in two years in the first week of December, says a study by the Delhi-based Centre for Science and Environment (CSE).

According to the study, the average PM2.5 level in the city’s air was 10 micrograms per cubic meter of air in a week in August, when the air was the cleanest compared with other months of the year. It jumped to 130 in the first week of December.

Across the river, in Howrah, too, the December air has been found to be critically polluted. The corresponding PM2.5 level are 19 and 136.

Environment scientists said August was the cleanest because of a combination of reasons, including limited economic activity in early stages of unlocking and meteorological factors such as rain, which had considerably neutralised the pollution load.

“In the first week of December, Calcutta has experienced its worst week and peak in last two years so far with PM2.5 level,” the report states.

“There were a few days when Calcutta and Howrah air pollution levels were higher than Delhi,” it says.

Experts associated with the study — which analysed the winter air data from October 1 to December 6, generated at all automatic air pollution measuring stations in the city —  pointed out that the combination of heightened economic activity and meteorological factors have contributed to the jump in pollution.

Indian Meteorological Department (IMD) said visibility had dropped considerably, a tell-tale indicator of heightened pollution. The wind speed has been low, a typical winter phenomenon, leading to slow dispersal of pollutants.

“The visibility in Alipore this morning was between 60 and 100 metres. Under normal circumstances it remains about 1,000 metres. The wind speed also remained relatively low,” said G.K. Das, of IMD Calcutta.

The CSE study found that the air quality recorded by the automatic monitoring station on the BT Road campus of Rabindra Bharati University reached “severe” in the first week of December. At the other six stations in the city, the quality was “very poor”.

According to the study, the average PM2.5 level in the city’s air was 10 micrograms per cubic meter of air. It jumped to 130 micrograms in the first week of December. 

“The disturbing part is the finding that the share of PM2.5 has increased significantly within PM 10,” said Anumita Roy Choudhury, an air pollution expert of the CSE who led the study.

Ultrafine PM2.5 is considered much more lethal compared with the relatively coarser PM10. “The percentage share of PM2.5 in overall PM10 has gone up to 60 per cent during high pollution episodes from around mid-November and remained high at over 50 per cent since then,” the report says.

“The spike in pollution can be attributed to anthropogenic well as meteorological factors. The cooler December air leads to an inversion phenomenon that results in trapping pollutants closer to the ground. Heightened economic activity, too, has contributed to the rise in pollution,” said Roy Choudhury.

“This is a typical and predictable winter trend when continuous emissions from local sources, including vehicles, industry, construction and episodic pollution from biomass burning, get trapped because of meteorological changes,” said Avikal Somvanshi, from the CSE air pollution team.

Roy Chowdhury stressed the need for “systemic changes” to reduce the city’s air pollution. “Systemic changes like switching public transport to cleaner fuels or phasing out old commercial vehicles will take time, but these changes will lead to a drop in the city’s air pollution level,” she said.

The report published by the CSE said that the three-year annual average of Calcutta’s air quality was 41 per cent poorer than the standards set by the Central Pollution Control Board for the country. For Howrah, it was 42 per cent poorer.

Asked about the study, Kalyan Rudra, the chairman of the state pollution control board, said: “I have not seen the CSE report. Unless one critically considers the impact of meteorological factors, it becomes a one-sided report.”

Kolkata air pollution: worst week in two years – Telegraph India
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EU takes Greece, Bulgaria to court over toxic air

Posted on December 4, 2020 by Respro® UK Ltd

The European Commission will take Bulgaria and Greece to the EU Court of Justice after both countries breached air pollution limits for years despite multiple warnings, the Commission said late on Thursday.

The two cases are the latest in a string of EU legal actions over poor air quality in countries including France, Italy and Romania, as Brussels seeks to clamp down on violations that threaten human health and the bloc’s pollution targets.

The Commission said it will refer Bulgaria to the EU’s top court for exceeding legal limits on particulate matter from 2015-2019 even after the court ordered the country’s government to address the issue in 2017.

Bulgaria could face financial penalties for flouting the earlier ruling. Bulgaria is one of the heaviest offenders in the European Union in terms of exceeding both annual and daily limits on particulate matter, the Commission said.

EU laws have required countries to limit particulate matter pollution since 2005. However, most of the bloc’s 27 members are set to miss targets this year to tackle dirty air.

The Commission also referred Greece to the court for exceeding particulate matter limits in the city of Thessaloniki for all but one year since 2005. “Efforts by the Greek authorities have to date been unsatisfactory and insufficient,” it said.

Air pollution is the biggest environmental health risk in Europe. Particulate matter contributed to around 379,000 premature deaths in 2018 in the EU, although this was 13% lower than in 2009, the European Environment Agency said in a recent report.

The Commission also referred Poland to the EU’s top court on Thursday for failing to protect forests and the wildlife that live there.

EU takes Greece, Bulgaria to court over toxic air | in-cyprus.com
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Air pollution where girl died in London ‘should have been treated as emergency’

Posted on December 1, 2020 by Respro® UK Ltd

Inquest into Ella Kissi-Debrah’s asthma death hears Lewisham council was slow to tackle issue

Illegal levels of air pollution in the area where a nine-year-old girl lived and died should have been treated as a public health emergency, an inquest heard.

Instead the London borough of Lewisham moved at a “glacial pace” to take steps to address toxic air from traffic where Ella Kissi-Debrah lived and went to primary school, the inquest in south London was told on Monday.

In a landmark legal case a coroner is being asked to rule that air pollution caused the death from an acute asthma attack of the primary school pupil in February 2013, a finding that would make legal history. It has never been identified as a cause of death before in the UK and this is thought to be the first case of its kind in the world.

Philip Barlow, an assistant coroner for inner south London, opened the hearing in which witnesses gave evidence via video link.

Barlow said the inquest would examine whether air pollution caused or contributed to Ella’s death, as well as how toxic air levels were monitored, the steps taken to reduce illegal levels of air pollution and what information was given to the public about reducing exposure.

He said it had already been decided that article 2 – the right to life – of the Human Rights Act, which scrutinises the role of public bodies in a person’s death, applied to the hearing.

As such, representatives from Lewisham council, the mayor of London and government will give evidence about their knowledge of the levels of toxic air around where Ella lived, the health impacts and what was being done to reduce the pollution.

The inquest was granted after years of campaigning by Ella’s mother, Rosamund Kissi-Debrah, when lawyers presented new evidence to the attorney general that directly linked Ella’s serious form of asthma and her death with the heavy traffic on London’s South Circular near her home. Her death coincided with one of the worst air pollution surges in her local area.

Giving evidence on Monday, David Edwards, the head of environmental health at Lewisham, accepted that levels of nitrogen dioxide (NO2) near the child’s home consistently exceeded the annual legal limit of 40µg/m3 between 2006 and 2010.

Asked by Barlow whether exposure to high levels of nitrogen oxides raised health concerns, he replied: “Yes, from my experience, yes it would.”

Representing the family, Richard Hermer QC asked: “For many years before Ella’s death Lewisham would have been aware that the levels of air pollution in the borough was placing the life and health of those who lived and worked there at risk?”

“Yes,” Edwards said.

The council official agreed the risk was particularly real to those suffering conditions such as asthma and was also increased for those who lived near high levels of traffic pollution.

Hermer said Ella’s home and school were in areas identified as of particular concern by the borough, both in terms of nitrogen oxide pollution and particulate matter.

“Taking what Lewisham would have known about what this meant in terms of deaths, what this meant about those at particular risk … this should have been treated as a public health emergency in the year before Ella’s death.”

Edwards replied: “Yes.”

But, Hermer said, it took the borough 10 years to draw up and adopt an action plan to try to tackle the problem. “That’s a glacial pace in the context of a public health emergency,” he said.

The borough was obliged when facing such a public health emergency to work to reduce air pollution levels and to inform those at risk.

Yet Ella’s mother, he said, in her evidence to be presented to the inquest, said she was never told about the risks of air pollution in relation to her daughter’s asthma.

“She is precisely the sort of person who should have been told about those risks, isn’t she?” Hermer asked.

“Yes,” Edwards replied.

Edwards told the hearing that ultimately the responsibility for tackling the levels of traffic using the South Circular through the borough lay with Transport for London and the national government.

“There are a number of people who have a greater impact than perhaps the local authority does,” said Edwards.

The hearing is due to last two weeks and will hear from government departments including Defra and the Department for Transport.

Ministers have repeatedly failed to bring air pollution from traffic within legal limits, for which they have been censured by judges several times.

In 2014 the first inquest into the child’s death made no mention of air pollution. The coroner ruled Ella had died of acute respiratory failure caused by severe asthma. This verdict was quashed in 2019 and a new inquest ordered after lawyers for the family presented evidence to theattorney general in 2018 from Prof Sir Stephen Holgate, one of the UK’s leading experts on air pollution.

The hearing continues.

Air pollution where girl died in London ‘should have been treated as emergency’ | Air pollution | The Guardian

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Potentially harmful aerosols concentrate in European urban centres

Posted on November 30, 2020 by Respro® UK Ltd

Atmospheric particles that increase levels of cellular oxidants when inhaled might be especially harmful. An analysis reveals which emissions should be limited to minimize the potential adverse health effects of such particles in Europe.

The inhalation of outdoor airborne particles can damage health and lead to premature death1,2. Writing in Nature, Daellenbach et al.3 report that certain components of atmospheric aerosols — those that have the potential to increase the oxidization of molecules in cells — might be responsible for most of the acute adverse effects of these particles in Europe. They also find that the distribution of these potentially harmful aerosols differs from that of the overall mass of aerosols, with hotspots in regions where the human population density is high. The overall mass concentration of particles is currently used as the key metric for assessing the risk of aerosols and to guide air-quality regulations. If the oxidation potential of aerosols is a stronger indicator of adverse effects, then the new results show that the evidence used at present to inform policymaking is deficient.

In many regions, the concentration of aerosol mass in the atmosphere has been monitored for decades. Correlations have thus been established1,2 between outdoor aerosol-mass levels and a diverse set of detrimental respiratory and cardiovascular diseases, along with a host of other conditions, such as diabetes and dementia.

However, the finding that a broad metric such as mass concentration is linked with these health effects is surprising, because aerosol particles are extremely complex. For example, they range continuously in diameter from tens of nanometres to tens of micrometres2,4. Particle size governs where particles are deposited in the respiratory system and whether they are transported to other organs, which in turn can influence the adverse effect produced2,4. Moreover, myriad chemical compounds can be found in aerosols, and the amount of each constituent varies continuously as particles grow and age4,5. Given the vast complexity of the particles we inhale, is there a better metric than mass concentration that could provide more-detailed insight into, and correlates more strongly with, the ill effects of aerosols on people?

One area of research has focused on a physiological mechanism known as oxidative stress to explain many of the varied adverse health outcomes of aerosols6,7. The idea is that particles carry oxidants into the lung and/or — probably a much worse effect — that specific components of the aerosol catalytically generate oxidants in cells when deposited in the lung or transported to other regions of the body. The oxidant load in cells is normally controlled, but if it becomes too high, the resulting damage to cellular components leads to oxidative stress and produces an overall inflammatory response.

Chemical assays have therefore been developed to analyse either the oxidants on particles or the aerosol components that generate oxidants in vivo, thereby allowing the oxidative potential (OP) — the capacity of particles to induce oxidative stress — to be measured. An ideal OP assay would comprehensively account for all the compounds that produce oxidative stress8 and their possible inter-actions with each other. Current assays arguably do not do this because they are sensitive to a few specific compounds.

To address this problem, Daellenbach et al. used three assays: one that quantifies the amount of oxidants on particles and two that assess the possible in vivo response. The authors loosely refer to all three as measures of aerosol OP, but agreement on more-precise terminology is needed in this field to clarify the source of oxidants (whether they were delivered by aerosols or formed in cells from aerosol components), and to aid consistency in the reporting of future results.

The authors collected about 90 samples of PM10 — particulate matter with a diameter of 10 micrometres or less — at each of 9 sites in Switzerland and Liechtenstein, and assessed the OP of the samples using the three assays. The authors then developed an air-quality model that predicted OP throughout Europe by extrapolating the data from the nine measurement sites, assuming that these locations were representative of all of Europe. They finally combined the model data with population-density data to calculate and compare human exposure to aerosol mass and OP. No comparisons were made to actual health data.

Daellenbach and co-workers found that OP was closely linked to human activities. The main sources of OP included organic aerosols produced indirectly from combustion, for example by residential wood burning, and metals from vehicle non-exhaust-pipe emissions (such as those produced by the use of brakes). This link to human activities resulted in the formation of OP hotspots at certain places with high population densities (Fig. 1).

By contrast, the overall mass distribution of PM10 was found to be more spatially uniform, because it was dominated by wind-blown mineral dust, organic aerosols derived indirectly from vegetation emissions, and sources of inorganic species, such as sulfate, nitrate and ammonium salts. An earlier study9 of aerosol-mass concentration also found that these salts contributed widely to aerosol mass and linked them to agricultural emissions (ammonium nitrate, for example, is a widely used fertilizer), thus suggesting that agricultural emissions should be a focus of efforts aimed at lowering premature mortality from aerosols over Europe. However, Daellenbach and colleagues show that these inorganic salts have low OP, and therefore are less concerning for human health. Clearly, any policy for protecting people from aerosols will be very different depending on which particle property — mass concentration or OP — is used to develop it.

It should be noted that evidence supporting the use of OP assays as indicators of health risks is mixed. The results of some toxicology tests of aerosol components do indeed correlate with OP determined by specific assays, and Daellenbach and colleagues show that this is the case for one of their assays. Several epidemiological studies have also shown that OP determined by some assays is more closely linked to specific adverse respiratory and cardio-vascular effects than is aerosol mass, but other studies do not10.

Moreover, it is difficult to compare studies that examine the effects of aerosol-mass concentration on human health with those that look at the effects of OP, because large data sets are needed for robust comparisons, and these are available only for mass-concentration studies. Instead, human exposure to OP is often predicted using computational models derived from a limited set of measurements, increasing the uncertainty of the results11,12. This is also an unavoidable limitation of Daellenbach and colleagues’ study.

Periodic reviews of the scientific bases for aerosol health effects by the World Health Organization1 and the US Environmental Protection Agency2 have so far found little evidence for replacing aerosol-mass concentration with metrics that focus more on the composition or source of the aerosols. But aerosol data founded on plausible biological mechanisms should be a better guide for future research addressing aerosol links to adverse health. Furthermore, as regulations and emissions driven by climate change alter the ambient aerosol composition in many regions, the usefulness of a mass-concentration metric might diminish. It is therefore prudent to explore other aerosol metrics, as Daellenbach et al. have done. Greater evaluation is now needed to help connect these metrics to human health data, to assess their utility.

Nature 587, 369-370 (2020)

Potentially harmful aerosols concentrate in European urban centres
Posted in Air Quality, Europe, Health Effects of Air Pollution, Medical Studies, World News | Tagged , , , , , , , , , , | Leave a comment