Air pollution: Research links black carbon to increased cancer risk

Posted on April 1, 2021 by Respro® UK Ltd

Long-term exposure to black carbon, a constituent of fine particle air pollution, could increase lung cancer risk by 30%, according to researchers in France.

Could stepping out for a breath of fresh air come with its own health risks? Research from France’s national institute of health and medical research, Inserm, published Wednesday, March 24 , singles out black carbon as a constituent of air pollution that could increase cancer risk, especially for lung cancer. Black carbon is produced by incomplete combustion, particularly related to vehicle traffic. Although, in 2013, the International Agency for Research on Cancer (IARC) categorized all fine particles as known human carcinogens, they may not all have exactly the same health impacts.

Black carbon could increase lung cancer risk

Since 1989, Inserm has been annually following up the health of some 20,000 volunteers (the Gazel cohort). This includes data on where participants have lived, as well as their habits, allowing for a better understanding of the researchers’ findings. “Those with the highest levels of exposure to black carbon since 1989 presented an approximately 20% increased cancer risk compared to those with the lowest exposures. An increased risk that rose to 30% for lung cancer,” reveal study authors Emeline Lequy and Bénédicte Jacquemin.

In light of the situation, the researchers consider that: “At an individual level, it is difficult to recommend measures for limiting exposure to black carbon from ambient air particles. However, it is possible to adjust public policies if we can show which air pollutants cause the most harm. So we hope that our findings will help to expand knowledge in order to guide and refine these policies, for example by taking specific measures against black carbon, which mainly comes from automobile traffic.”

While continuing to research the health impact of black carbon, the researchers also aim to study the health impacts of other specific pollutants, notably metals.

Air pollution: Research links black carbon to increased cancer risk
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Urban and transport planning linked to 2,000 premature deaths per year in Barcelona and Madrid

Posted on March 31, 2021 by Respro® UK Ltd

Failure to comply with international exposure recommendations for air pollution, noise, heat and access to green space is associated with more than 1,000 deaths per year in Barcelona and more than 900 in Madrid, accounting for 7% and 3% of overall premature mortality, respectively.

This is the conclusion of a new study by the Barcelona Institute for Global Health (ISGlobal), a center supported by the “la Caixa” Foundation. This study is the first to estimate premature mortality impacts and the distribution by socioeconomic status of multiple environmental exposures related to urban planning and transport in the two cities.

Today, more than half of the global population lives in cities. In Spain, this trend is even more pronounced, with 80% of the population living in urban areas. Madrid and Barcelona are two of Europe’s most populous cities, and they also have some of the highest rates of socioeconomic inequality among inhabitants. Recent studies in European cities such as Vienna, Bradford and Barcelona have shown that a considerable proportion of the premature mortality burden—between 8% and 20%—is associated with poor urban and transport planning.

The new study, published in Environmental Research, estimated the impact of non-compliance with international exposure level recommendations for air pollution—fine particulate matter (PM2.5) and nitrogen dioxide (NO2)—as well as excess heat, traffic noise and lack of green space on residents over 20 years of age in Barcelona and Madrid, cities with different urban planning practices. Whereas Madrid is structured around a central nucleus where most economic activity is concentrated, Barcelona is a compact city whose economic activity is distributed across different neighborhoods.

The study focused on identifying environmental inequities. “Our goal was to identify the population groups that were most exposed and most vulnerable to the effects of poor urban and transport planning,” commented ISGlobal researcher Tamara Iungman, lead author of the study. As for methodology, the researchers used a tool called Urban and Transport Planning Health Impact Assessment (UTOPHIA), which was developed by a team at ISGlobal. “We compared current exposure levels with international recommendations and estimated the fraction of preventable premature deaths that could be avoided if we were to comply with those recommendations,” explained Iungman.

Attributable Deaths

The findings showed that non-compliance with WHO’s exposure recommendations for air pollution, noise, and access to green space, along with excess heat, were associated with 1,037 premature deaths per year in Barcelona. Fine particulate air pollution was the exposure associated with the highest premature mortality, accounting for 524 deaths per year (48% of total attributable deaths), followed by lack of green space (277 deaths), exposure to traffic noise (124 deaths), heat (112 deaths) and exposure to NO2 (12 deaths).

For Madrid, the total number of deaths attributable to non-compliance with international recommendations was 902. Lack of green space was the exposure associated with the highest premature mortality (337 deaths per year), followed by excessive heat (244 deaths), NO2 air pollution (207 deaths), PM2.5 air pollution (173 deaths) and noise (148 deaths).

An earlier ISGlobal study attributed 20% of premature mortality in Barcelona to poor urban and transport planning. “The lower values obtained in this health impact assessment of Barcelona and Madrid—7.1% and 3.4%, respectively—could be attributed to the fact that physical activity was not included in this study, in addition to improvements in adverse exposure levels in recent years, as well as the different methodology used to estimate the mortality attributable to noise,” commented Iungman.

Differences Between Barcelona and Madrid

With better urban and transport planning, Barcelona could avoid nearly twice as many deaths as Madrid: 72 versus 33 deaths per 100,000 inhabitants. “This difference can be partly explained by the fact that the scientific evidence associates higher mortality with exposure to PM2.5, which is higher in Barcelona; another explanation would be the greater traffic and population density in Barcelona than in Madrid, given that its area represents 1/6th of Madrid’s”, explained ISGlobal researcher Natalie Mueller, coordinator of the study.

With an annual average of 15 μg/m3, Barcelona exceeded the maximum level recommended by the World Health Organisation (WHO) for PM2.5 (10 μg/m3). For NO2 levels, however, the city’s annual average of 37 μg/m3 was under the recommended maximum of 40 μg/m3. Madrid exceeded the WHO recommendations on both counts, with an annual average of 11 μg/m3 for PM2.5 and 42 μg/m3 for NO2.

The main difference between the two cities was in air pollutants. The findings showed higher levels of fine particulate matter in Barcelona and NO2 in Madrid, as well as different spatial distributions: high levels of PM2.5 throughout Barcelona and higher levels of NO2 in the center of the Spanish capital. “While the main source of NO2 emissions is local motor-vehicle traffic, fine particulate matter has a higher dispersion capacity and is also associated with other combustion sources besides traffic,” commented Mueller. “The port and the large industrial areas near Barcelona could influence the high levels of fine particulate matter in the city.”

As for green space, the vast majority of the population in Madrid and Barcelona—84% and 95%, respectively—did not have adequate access to these natural environments according to the standards of the WHO, which recommends that people should live within 300 meters of a green space measuring at least half a hectare. This widespread lack of access to green space shows that “in order for green spaces to have health benefits—in addition to mitigating other exposures such as noise and excess heat—it is necessary to consider not only their availability in the city, but also their distribution so that residents can access them on foot,” commented Mueller.

With regard to noise, 97% of the population of Madrid and 96% of the population of Barcelona were exposed to traffic noise levels higher than the WHO’s recommended values. “Both cities had a considerable mortality burden attributable to traffic noise, which underscores how important it is to reduce noise to improve the health of the population,” argued Mueller.

Although there are no specific guidelines for heat, the researchers calculated the temperature corresponding to the smallest number of heat-related deaths in each city: 22.5°C for Barcelona and 21.5°C for Madrid and estimated the impacts of a potential reduction of 1º. “The two cities had similar attributable mortality rates and we found correlations between less green space and higher levels of heat and noise,” added Iungman.

Environmental Inequities

The findings show that poor urban and transport planning in Barcelona is associated with higher mortality in census tracts with lower socioeconomic status, whereas in Madrid the attributable mortality burden varied by environmental exposure. Although air pollution, lack of green space and excessive heat are widespread problems in Barcelona, attributable mortality rates were overall higher in the most deprived areas. Thus, populations in the most deprived census tracts had a mortality risk 1.26 times higher than that of the least deprived groups, probably because of an already higher underlying vulnerability.

In Madrid, the most deprived neighborhoods had higher exposure to PM2.5 and heat than the least deprived neighborhoods, while the inverse was true for NO2 and noise. This is probably due to the fact that lower socioeconomic population subgroups reside more peripheral and closer to industrial areas, where the cost of living is cheaper -and thus they are more exposed to PM2.5 and heat-, while middle and upper middle socioeconomic population reside in Madrid highly trafficked city center, with greater exposure to NO2 and traffic noise. With respect to green spaces, lack of access affected people of both low and middle socioeconomic status. This pattern was also reflected in its attributable mortality, where only the least deprived areas were the ones having less adverse impacts, probably due to lower underlying vulnerability and better general health status.

Co-author Mark Nieuwenhuijsen, Director of the Urban Planning, Environment and Health Initiative at ISGlobal, commented: “This analysis is in line with previous research showing that people living in more deprived neighborhoods tend to be more exposed to harmful environmental exposures compared to those living in wealthier areas, although this inequity varies according to the design characteristics and historical development of each city.”

“This study shows that environmental exposures have a large impact on premature mortality and underscores the importance of designing cities with health impacts in mind, valuing the specificities of each urban environment and prioritizing disadvantaged populations,” concluded Nieuwenhuijsen. “Health impact assessments are a powerful tool for guiding policymakers towards cities that are healthy, sustainable and fair for all residents.”

via Urban and transport planning linked to 2,000 premature deaths per year in Barcelona and Madrid

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Pollution forces Nepal schools to close for the first time

Posted on March 30, 2021 by Respro® UK Ltd

Nepal on Monday ordered schools to close as choking smog enveloped the capital Kathmandu, in the first-ever shutdown of the country’s education sector because of pollution.

Kathmandu is currently ranked among the most polluted cities in the world, with the air quality index (AQI) readings well above 300, the highest level of concern, during the weekend.

“It has been decided that educational institutions will be closed until Friday. As far as we are aware, this is the first time schools have been closed because of pollution,” Deepak Sharma, the Ministry of Education spokesman, told AFP.

The government has also urged people to stay indoors and to avoid construction and burning trash.

Experts say that raging wildfires in several parts of the country combined with stagnant atmospheric conditions have caused the thick smog to cover many districts.

“There is not enough movement in the atmosphere right now so pollutants, contributed also by the wildfires, have been trapped to cause the air quality to deteriorate,” said Min Kumar Aryal, a meteorologist at Nepal’s Meteorological Forecasting Division.

On Twitter, Kathmandu residents complained of “stinging eyes” and “itchiness” because of the pollution.

Low visibility caused by the smog has disrupted flights at Kathmandu airport, leaving passengers facing hours-long delays.

The country’s only international airport was temporarily closed on Friday as visibility dropped to 1,000 metres, according to an airport official, before reopening on the same day.

Pollution forces Nepal schools to close for the first time – France 24
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California’s Tougher Diesel Emissions Rules Cut Related Deaths in Half: Study

Posted on March 30, 2021 by Respro® UK Ltd

California’s strict limits on diesel air pollution appear to have paid off.

Since the limits were added in 1990, diesel exhaust-related deaths have been halved, with the largest reductions in deaths seen in lower-income communities, a new study finds.

By 2014, California saw a 78% decrease in diesel emissions, while diesel emissions in the United States fell by only 51%.

The number of annual diesel-related cardiopulmonary deaths in California between 1990 and 2014 was half what would have occurred if the state had the same reduction in diesel emissions as the rest of the country, the researchers estimated.

They added that California’s level of reductions in such deaths could be achieved nationwide if the rest of the country adopted similar restrictions.

“Everybody benefits from cleaner air, but we see time and again that it’s predominantly lower-income communities of color that are living and working in close proximity to sources of air pollution, like freight yards, highways and ports. When you target these sources, it’s the highly exposed communities that stand to benefit most,” said study author Dr. Megan Schwarzman, a physician and environmental health scientist at the University of California, Berkeley’s School of Public Health.

“It’s about time, because these communities have suffered a disproportionate burden of harm,” Schwarzman added in a university news release.

Diesel exhaust contributes significantly to a type of air pollution called fine particulate matter (PM2.5), which can affect children’s lung development, trigger airway inflammation and exacerbate asthma and cardiopulmonary diseases.

The researchers also pointed out that exposure to PM2.5 has been linked to poor outcomes from COVID-19, and that nonwhite communities are disproportionately affected by both.

Diesel exhaust has been designated a human carcinogen by California’s Office of Environmental Health Hazard Assessment (OEHHA).

“There are hundreds of studies around the world that link particulate matter exposure and premature death,” said study co-author Álvaro Alvarado, an air pollution specialist at OEHHA. “In cities with higher levels of air pollution, there are also higher hospitalization rates for respiratory and cardiovascular illnesses and more emergency room visits for asthma.”

The findings were published March 25 in the journal Science.

More information The U.S. National Institute of Environmental Health Sciences has more on air pollution and your health.

SOURCE: University of California, Berkeley, news release, March 25, 2021

California’s Tougher Diesel Emissions Rules Cut Related Deaths in Half: Study | Health News | US News
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Air pollution and physical exercise: when to do more or less

Posted on March 30, 2021 by Respro® UK Ltd

Physical activity is important in preventing heart and blood vessel disease in young people so long as they don’t undertake very strenuous activity on days when air pollution levels are high, according to a nationwide study of nearly 1.5 million people published today (Tuesday) in the European Heart Journal [1].

Until now, little has been known about the trade-offs between the health benefits of physical activity taking place outdoors and the potentially harmful effects of air pollution. Previous research by the authors of the current study had investigated the question in middle-aged people at a single point in time, but this is the first time that it has been investigated in people aged between 20-39 years over a period of several years. In addition, the researchers wanted to see what happens when people increase or decrease their physical activity over time.

The researchers from Seoul National University College of Medicine (South Korea), led by Professor Sang Min Park, looked at information from the National Health Insurance Service (NHIS) in South Korea for 1,469,972 young Koreans living in cities, who underwent two consecutive health examinations during two screening periods: 2009-2010 and 2011-2012. They followed up the participants from January 2013 to December 2018.

At each health check-up the participants completed a questionnaire asking about their physical activity in the past seven days and this information was converted into units of metabolic equivalent task (MET) minutes per week (MET-mins/week). The participants were divided into four groups: 0, 1-499, 500-999 and 1000 or more MET-mins/week. European Society of Cardiology guidelines recommend people should try to do 500-999 MET-mins/week and this can be achieved by, for example, running, cycling or hiking for 15-30 minutes five times a week, or brisk walking, doubles tennis or slow cycling for 30-60 minutes five times a week. [2]

The researchers used data from the National Ambient Air Monitoring System in South Korea to calculate annual average levels of air pollution, in particular the levels of small particulate matter that are less than or equal to 10 or 2.5 microns in diameter, known as PM10 and PM2.5 [3]. The amount of exposure to air pollution was categorised at two levels: low to moderate (less than 49.92 and 26.43 micrograms per cubic metre, μm/m3, for PM10 and PM2.5 respectively), and high (49.92 and 26.46 μm/m3 or more, respectively).

Dr Seong Rae Kim, first author of the paper, said: “We found that in young adults aged 20-39 years old, the risk of cardiovascular diseases, such as stroke and heart attack, increased as the amount of physical activity decreased between the two screening periods in the group with low levels of exposure to air pollution.

“However, in the group with high levels of exposure to air pollution, increasing the amount of physical activity to more than 1000 MET-min/week, which is more than internationally recommended levels for physical activity, could adversely affect cardiovascular health. This is an important result suggesting that, unlike middle-aged people over 40, excessive physical activity may not always be beneficial for cardiovascular health in younger adults when they are exposed to high concentrations of air pollution.”

He continued: “Ultimately, it is imperative that air pollution is improved at the national level in order to maximise the health benefits of exercising in young adults. These are people who tend to engage in physical activity more than other age groups while their physical ability is at its best. If air quality is not improved, this could result in the incidence of cardiovascular diseases actually increasing despite the health benefits gained from exercise.”

The researchers adjusted their results to take account of factors that could affect them, such as age, sex, household income, body mass index, smoking and alcohol consumption. During the follow-up period there were 8,706 cardiovascular events. Among people exposed to high levels of PM2.5 air pollution, those who increased their exercise from 0 to 1,000 MET-min/week or more between the two screening periods had a 33% increased risk of cardiovascular disease during the follow-up period compared to those who were physically inactive and did not increase their exercise, although this result was slightly weaker than that needed to achieve statistical significance. This means an extra 108 people per 10,000 might develop cardiovascular disease during the follow-up period.

Among people exposed to low to moderate levels of PM2.5, those who increased their physical activity from none to 1,000 MET-min/week or more had a 27% reduced risk of developing cardiovascular disease compared to those who remained inactive, although this result was also not quite statistically significant. This means 49 fewer people per 10,000 might develop cardiovascular disease during the follow-up period.

Dr Kim said: “These results are very close to statistical significance. In fact, a further analysis presented in Figures 2 and 3 of our paper shows that statistical significance was achieved for increasing and decreasing amounts of physical activity.” For low to moderate levels of PM10 air pollution, there was a statistically significant 38% or 22% increased risk of cardiovascular disease among people who started off doing 1,000 MET-min/week or more and then reduced their activity to none or to 1-499 MET min/week, respectively, compared to people who maintained the same high level of activity. These results were statistically significant and mean that 74 and 66 extra people per 10,000 respectively would develop cardiovascular problems during the follow-up period.

Professor Sang Min Park, who led the research, said: “Overall, our results show that physical activity, particularly at the level recommended by European Society of Cardiology guidelines, is associated with a lower risk of developing heart and blood vessel disease among young adults. However, when air pollution levels are high, exercising beyond the recommended amount may offset or even reverse the beneficial effects.”

The study cannot show that air pollution causes the increased cardiovascular risk, only that it is associated with it. Other limitations are that there was no information on whether or not the exercise took place indoors or outdoors; participants may not have remembered correctly the amount of exercise they took in the seven days before they attended their screening interview, although this is unlikely; PM2.5 data were only measured in three major cities; and the researchers did not investigate the short-term effects of exposure to air pollution.  

Air pollution and physical exercise: when to do more or less
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Sandstorms turn sun blue and sky yellow in Beijing

Posted on March 29, 2021 by Respro® UK Ltd

Thick dust carrying extremely high levels of hazardous particles blows in from drought-hit Mongolia

The second sandstorm to hit China in less than a fortnight has reversed the colours of the sky, turning the sun blue and the heavens yellow.

Beijing woke on Sunday morning shrouded in thick dust carrying extremely high levels of hazardous particles.

The sandstorm was fuelled by winds from drought-hit Mongolia and north-western China.

Visibility in the city was reduced, with the tops of some skyscrapers obscured by the sandstorm. Pedestrians were forced to cover their eyes as gusts of dust swept through the streets.

The China Meteorological Administration issued a yellow alert on Friday, warning that a sandstorm was spreading from Mongolia into northern Chinese provinces including Inner Mongolia, Shanxi, Liaoning and Hebei, which surrounds Beijing.

As the sandstorm hit Beijing on Sunday morning, air pollution levels rose to a maximum level of 500, according to Beijing’s real time air quality index. Levels of the pollutant PM10, which can penetrate the lungs, passed 2,000 micrograms per cubic metre.

Levels of PM2.5, smaller particles that can penetrate the bloodstream, reached 462. The World Health Organization recommends average daily PM2.5 concentrations of just 25.

The storm caused havoc at airports in Inner Mongolia, with more than half of flights cancelled from the Baotou and Chifeng airports due to poor visibility, the South China Morning Post reported.

The China Meteorological Administration said the recent sandstorms originated from Mongolia, where relatively warmer temperatures this spring and reduced rain resulted in larger areas of bare earth.

“The dynamics for sandstorms and transmission of dust are good now,” Zhang Tao, chief forecaster for China’s Central Meteorological Observatory told state-run People’s Daily on Monday.

Zhang said north and northwestern China had less snow cover and rain this year and that temperatures since February had been higher, leading to further drying and dusty weather, kicked up by stronger than usual winds.

Average temperatures in Mongolia and northern China were about 6°C higher than normal in March, according to Zhang.

Northern China has long suffered sandstorms as deserts in the region spread further south, with deforestation intensifying the frequency during Mao Zedong’s Great Leap Forward period from 1958 to 1961.

Large-scale deforestation is also considered a factor in China’s dust storms. Beijing has planted a “great green wall” of trees to trap incoming dust, as well as trying to create air corridors that channel the wind and allow sand and other pollutants to pass through more quickly.

via Sandstorms turn sun blue and sky yellow in Beijing | Air pollution | The Guardian
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Lockdown did not reduce air pollution from tyre wear in London

Posted on March 26, 2021 by Respro® UK Ltd

Less traffic meant less congestion, but the remaining vehicles went faster

I asked William Hicks how he felt when lockdown suddenly happened in the middle of his year-long air pollution investigation. “Excited,” he replied. Not the answer that I expected. “It was like moving the field laboratory to a whole new road.” Hicks, and his team from Imperial College London, were studying tiny particles from tyres, brakes and road surfaces on London’s Marylebone Road.

The inside of the field laboratory is a noisy environment full of the rattle of pumps, as an array of equipment measures the size and chemical nature of the air pollution. Hicks was measuring metal particles in the air to work out how much pollution came from each source. Barium particles are released from brake pads and zinc, used to volcanise rubber.

During my visits to the field laboratory I like to take a few minutes to climb up among the sampling equipment on the roof and watch the remarkably regular daily pattern of the traffic, but in lockdown 32% of the traffic disappeared. Less traffic meant less congestion, but the remaining traffic went faster. Brakes particles decreased with less stop-start conditions but the air pollution from tyres stayed the same. Faster traffic meant more tyre wear from each vehicle.

A 2017 study estimated that tyre wear-and-tear accounts for between 5% and 10% of microplastics entering our oceans each year. Another estimate from International Union for Conservation of Nature and Natural Resources puts this figure at about 28%. These figures make wear-and-tear from tyres at least as important as plastic bottles, bags and fibres released from clothing during washing. Heavier vehicles also produced more particle pollution than lighter ones; lorries and buses produced about four times more brake and tyre wear compared with cars and vans.

The UK and governments around the world plan to clean up exhausts and eventually to abolish combustion engines all together, but as Hicks explained, “pollution from brakes, tyres and road surfaces are here to stay”. Although electric lorries may be some time off, regenerative braking in hybrid, and electric, cars, buses and vans should decrease the toxic metal particles from brakes. This involves using the electric motor, instead of friction brakes, to slow the vehicle, recharging the battery. But controlling tyre and road wear will not be easy. The polluted roads of the future may not be the slow congested streets in city centres but the busy faster trunk roads. Less and slower traffic may be one solution, along with lighter vehicles.

Lockdown did not reduce air pollution from tyre wear in London | Pollution | The Guardian
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Health Risks Linked to Air Pollution at Levels Below WHO Targets

Posted on March 25, 2021 by Respro® UK Ltd

Hazy air days often followed by uptick in cardiovascular, respiratory deaths

A short-term rise in nitrogen dioxide air pollution could be tied to a bump in local mortality rates the next day, researchers showed in a large international study.

Across 398 cities (located mostly in the U.S., Europe, and Asia), each 10 μg/m3 increase in ground-level NO2 concentration was associated with increases in mortality the next day that persisted after adjustment for other air pollutants:

– Total mortality up 0.46%

– Cardiovascular mortality up 0.37%

– Respiratory mortality up 0.47%

Concentration-response curves, based on data from 1973 to 2018, were almost linear with no minimum threshold for harm, reported Haidong Kan, MD, PhD, of Fudan University in Shanghai, and colleagues in an epidemiological study published online in The BMJ.

“This result suggests that NO2 is associated with considerable health risks even at levels below health based standards and guidelines, including the current WHO air quality guidelines,” the group wrote.

Cities participating in the study had a median average annual nitrogen dioxide concentration of 26.9 μg/m3. The WHO sets a target of 40 μg/m3 in annual mean concentration of NO2 in air quality guidelines.

Ambient nitrogen dioxide primarily comes from vehicle and power plant emissions. The U.S. Environmental Protection Agency concluded in 2016 that there is a causal relationship between short-term exposure to NO2 and respiratory effects; evidence was deemed insufficient to blame exposure for total mortality and cardiovascular effects, however.

“Our findings from this multi-location analysis add to the supporting evidence for causal associations between short term exposure to NO2 and non-respiratory endpoints,” Kan and colleagues wrote.

“Although reduction of NO2 to zero is infeasible, our analysis provides insight into the public health benefits of substantial reductions in NO2, suggesting considerable health benefits from stricter control of NO2 emissions and tightening of the regulatory limits of NO2 in future revisions of WHO air quality guidelines,” they noted.

For their epidemiological study, the investigators drew upon the Multi-City Multi-Country Collaborative Research Network. Mortality data, obtained from local authorities within each country, captured 62.8 million total deaths from 1973 to 2018.

That most data were obtained from select developed areas precluded global generalization of the findings, Kan’s team cautioned.

Furthermore, their database was subject to potential exposure misclassification and coding errors.

via https://www.medpagetoday.com/publichealthpolicy/environmentalhealth/91793

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