Gas flares tied to premature deaths

Posted on March 1, 2022 by Respro® UK Ltd

Newly published research by Rice University environmental engineers suggests flaring of natural gas from oil and gas fields in the United States, primarily in North Dakota and Texas, contributed to dozens of premature deaths in 2019.

Satellite observations and computer models can link gas flares to air pollution and health, according to Daniel Cohan of Rice’s George R. Brown School of Engineering and his colleagues, who published their findings in the journal Atmosphere.

Oil and gas producers flare excess gas when infrastructure to bring it to market is unavailable. While flaring reduces the direct venting of the powerful greenhouse gas methane into the atmosphere, it also produces black carbon particles, also known as soot or particulate matter. These particles, smaller than 2.5 microns in diameter, can impair lung function and cause respiratory disease, heart disease and strokes.

The Rice team partnered with researchers from the Clean Air Task Force to produce calculations, based on infrared satellite observations of oil fields where 97% of flaring takes place, showing that the United States emitted nearly 16,000 tons of black carbon in 2019. The researchers used computationally efficient reduced-form models to estimate that 26–53 premature deaths were directly attributable to air quality associated with flares.

“Our research shows that flaring not only wastes a valuable fuel but is deadly, too,” said Cohan, an associate professor of civil and environmental engineering, who led the study with first-year graduate student Chen Chen. “Particulate matter causes more deaths than all other air pollutants combined, and flares are an important source of it.”

Flares aren’t the only source of particulate matter in the atmosphere. Particles are also produced whenever fossil fuels are burned, including by vehicles, and by wildfires, cooking meat and other sources.

The researchers’ models accounted for the fact that the heat content of the burning fuel varies widely across oil and gas fields and has a strong impact on black carbon emissions.

“For this study, we used 10 different emission factors for flares, and using the reduced-form models made the calculations super-fast,” Chen said. “Other studies show a good relationship between full and reduced-form models, so we’re confident in our results.”

Cohan said black carbon emissions also contribute to climate change by absorbing solar radiation in the atmosphere, influencing the formation of clouds and accelerating snow and ice melt, though all of those consequences were beyond the scope of their study.

The researchers noted there are cost-effective technological alternatives to flaring, including gas-gathering pipelines, small-scale gas utilization and reinjecting excess back into the ground. While the Environmental Protection Agency (EPA) is considering regulations to reduce both methane emissions and associated gas flaring, there are currently no federal limits to the widespread practice of flaring, they wrote.

“We initially didn’t think about publishing a peer-reviewed paper,” Chen said. “We were asked by the Clean Air Task Force to estimate these health impacts to support their advocacy to reduce harmful pollution from oil and gas production. But because the clearly shows dozens of deaths per year due to flaring, we thought a paper would provide regulators with new angles to consider in their efforts to minimize the impacts of oil and gas air pollution.”

Gas flares tied to premature deaths
Posted in Air Quality, Health Effects of Air Pollution, USA, USA & Canada | Tagged , , , , , , , , , , | Leave a comment

Mopping can create air pollution that rivals city streets

Posted on February 28, 2022 by Respro® UK Ltd

Cleanliness may be next to godliness, but a new study suggests it could have an unexpected downside: A few minutes of mopping indoors with a fresh-scented cleaning product can generate as many airborne particles as vehicles on a busy city street. The finding suggests custodians and professional cleaners may be at risk of health effects from frequent exposure to these suspended tiny particles, known as aerosols.

“I was absolutely amazed that mopping produced potentially harmful aerosols at similar rates to those generated by traffic on a busy street,” says Nicola Carslaw of the University of York who investigates indoor air pollution but was not involved with the study. “The people who should be paying particular attention to this paper are NIOSH, the National Institute for Occupational Safety and Health,” adds Glenn Morrison, an environmental scientist at the University of North Carolina, Chapel Hill, who was also not involved. “There is a lot of particle formation during these cleaning events, even under conditions that we would consider very normal.æ

The air in homes, schools, and offices can sometimes be dirtier than the air outdoors, even in cities with pollution problems. Any kind of burning—candles, incense, cigarettes—is bad. Gas stoves and cooking food also spew unhealthy particles into the air, which can cause asthma and other health problems when breathed in. Other significant sources of indoor air pollution include personal care and cleaning products, whose fragrances contain volatile organic chemicals that react with ozone in the air to form small particles known as aerosols.

One molecule of concern is limonene, a commonly added to cleaners and furniture polish to help remove oil and grease. The lemon-scented molecule reacts readily with ozone, an outdoor pollutant that is the main ingredient in smog. When ozone wafts into buildings, it reacts with limonene and similar molecules called monoterpenes, turning them into peroxides, alcohols, and other molecules that grow into airborne particles. Small particles can lodge deep in the lungs, irritating cells and—at high enough exposure—leading to health problems, such as asthma. In vulnerable people, particulate air pollution can cause heart attacks and strokes.

Previous studies found cleaning products can generate such pollution. But not all of these experiments were realistic or detailed. The new study was designed to reveal, minute by minute, what happens with airborne reactions during a typical floor cleaning. Researchers brought their lab instruments into a room with an air volume of 50 cubic meters, about half the size of a semitrailer container. In the morning, they mopped the floor for 12 to 14 minutes with a terpene-based cleaner. Then, they used state-of-the-art instruments to monitor the molecules and particles as they reacted over the next 90 minutes. “This is the first study that really looked at the entire chemical process under realistic indoor conditions,” says co-author Philip Stevens, an atmospheric chemist at Indiana University, Bloomington.

After the researchers collected data from the room, they calculated how many particles smaller than half a micron a person there would inhale during mopping. Using a standard computer model, the team reports today in Science Advances that an average person would breathe in about 1 billion to 10 billion nanoparticles each minute. That’s equivalent to vehicle traffic on a busy street in a typical U.S. or European city. It’s also about the same as cooking with a gas stove or lighting a candle.

The researchers also detected short-lived molecules called radicals, like hydroxyl and hydroperoxyl, that are known to drive reactions that create particles outdoors. But the new research shows they can also form indoors, from reactions between monoterpenes and ozone. “The rate at which it occurs indoors is surprising,” says co-author Colleen Rosales, a postdoc at the University of California, Davis. Carslaw adds that this “really important finding” should raise concerns about indoor air quality.What about opening windows? The ventilation in the laboratory, similar to a typical office building, was not powerful enough to remove the particles. Ventilation can also be a double-edged sword, researchers say. It removes particles, but it can also bring in more dangerous ozone from outdoors.

Keeping ozone levels below one part per billion—either by reducing ventilation or using activated carbon air filters—would help reduce particle formation, the researchers say. So would cleaning in the morning or evening, when ozone levels tend to be lower, and avoiding products with limonene or other kinds of terpenes. Portable air filters can also reduce the concentration of particles inside rooms, says co-author Brandon Boor, a civil engineer at Purdue University.

Fortunately, time also helps: In the hours after cleaning, the newly formed particles grow in size, after which they settle out of the air. While resting on surfaces, the particles are harmless.

The larger problem, Boor says, is the scarcity of regulations for the design and operation of buildings—and the use of various common chemicals inside them—with respect to air quality. “We need to pay closer attention to what’s going on in indoor environments.”

Mopping can create air pollution that rivals city streets | Science | AAAS
Posted in Air Quality, Asthma, Health Effects of Air Pollution | Tagged , , | Leave a comment

Could more nature and less air pollution prevent ADHD?

Posted on February 25, 2022 by Respro® UK Ltd

A study tracing the early lives of roughly 30,000 children in Metro Vancouver has found lower access to green space and increased levels of air pollution lead to higher levels of ADHD

The less air pollution and more green space a child is exposed to, the less likely they are to develop attention-deficit hyperactivity disorder (ADHD), a sweeping Metro Vancouver-wide study has found. 

The pathbreaking research, published in the journal Environment International, followed a cohort of nearly 30,000 children born in 2000 and 2001. 

Tracing a three-year exposure period, researchers from the University of British Columbia analyzed the combined impacts of satellite-measured green space, noise and concentrations of fine particulate matter smaller than 2.5 micrometres (PM 2.5) on the development of ADHD. Seven years after the exposure period, over 1,200 ADHD cases were diagnosed.

Noise was found to have no effect. But lower the amount of green space or increase the levels of air pollution, and the twin effects can heighten the risk of ADHD by up to 62 per cent, found researchers. The result: “children living in greener neighbourhoods with low air pollution had substantially lower risk of ADHD compared to those with higher air pollution and lower green space exposure,” concluded the study.

“I was surprised that we saw this much of a difference,” said Michael Brauer, a co-author on the study and a researcher examining the built environment and human health at UBC’s School of Population and Public Health. 

“Given that there’s not a lot of things about ADHD that we can change at a societal level, it is a pretty big effect.”

PM2.5 is the main constituent of wildfire smoke, something only expected to worsen in the coming decades. Outside of the fire season, Metro Vancouver says it’s also produced through the burning of fossil fuels in everything from transportation, industry and agriculture. It has been considered a carcinogen since 2013. Across the world, the World Health Organization estimates almost 80 per cent of the deaths related to PM2.5 could be avoided if its guidelines were followed. 

Not all air pollutants were correlated with an increased risk of developing ADHD. Nitrogen dioxide — which together with PM 2.5 and ground-level ozone contributes to over 15,000 annual deaths across Canada and 1,900 in B.C. — was not found to be connected with the development of ADHD.

Brauer says the biggest two sources of air pollution driving the variation in Metro Vancouver were traffic and space heating, including wood-burning and natural gas fireplaces, and gas boilers. 

Closer to the coast and at higher elevations, pollution levels tended to be lower due to ocean breezes and the tendency of pollution to settle in low-lying areas. The worst-hit areas tended to be near major traffic arteries, along highways, major truck routes and the region’s ports.  

A neurodevelopmental disorder, ADHD is thought to affect five to 10 per cent of children and adolescents. Throughout a person’s life, it can affect their academic performance and their ability to socialize and work.

As the researchers put it, ADHD has “considerable impacts on individual wellbeing, health care, and the economy.” 

The study is part of a wider attempt to understand the environmental health hazards from air pollution and how green spaces can dampen their impacts. 

In October 2021, another Metro Vancouver-wide study from several of the same UBC researchers concluded living near green spaces improves a children’s chances of hitting key developmental milestones, including emotional maturity, language skills and even general knowledge. 

Living near green spaces, found the 2021 study, could improve childhood development, partly by reducing the negative effects of air and noise pollution — both have been found to increase stress, sleep disturbances and central nervous system damage in children.

The latest round of research adds to a growing body of evidence of the benefits of green space on human health.

In other parts of the world, past research has found that access to green space can promote a huge range of positive health outcomes for all ages, from increased physical activity and social cohesion to reduced cardiovascular disease and dementia rates. Others have found similar benefits when people regularly expose themselves to bodies of water, known by some as “blue space.”

Increased density of trees can also create a buffer for extreme heat and, in the winter, act as a thermal blanket that will reduce heating bills should a deep freeze set in. But how green spaces are distributed across the Metro area can reveal some huge inequalities.

Of the nearly 600 British Columbians who died from extreme temperatures during late June’s heatwave, more were killed in low-income areas, where people lived alone and with little green space. On Vancouver’s Downtown Eastside, Canada’s poorest neighbourhood, hospitalizations tripled, with more people admitted to emergency rooms due to heat than anywhere else in the city.

Scientists know how trees protect us from heat. But how more access to green space makes people healthier over the long term is unclear. 

“Instead of saying green is good, we’re providing more concrete pathways,” Ingrid Jarvis told Glacier Media last fall.

At the time, Jarvis said the research shows that everyday “micro-contacts” with nature can positively affect a child’s long-term physical and mental health. 

“This is one more thing,” added Brauer, referring to the group’s latest study. “There’s not a lot known about factors that you can modify. So what we tend to do when kids are diagnosed with ADHD is put them on medication.”

“We could be raising healthier kids.”

Ultimately, their findings have big repercussions for how planners design neighbourhoods in a region expected to add another million people to its population by 2040.

In the past, the group of UBC researchers have sent findings to Metro Vancouver, where it was distributed to all 21 jurisdictions and various committees. 

Could more nature and less air pollution prevent ADHD? – Vancouver Is Awesome
Posted in Air Quality, Canada, Health Effects of Air Pollution, Medical Studies, USA & Canada | Tagged , , , , , | Leave a comment

Children with higher exposure to air pollution and lower exposure to green space have 62% increased risk of ADHD

Posted on February 24, 2022 by Respro® UK Ltd

Children living in areas with higher air pollution due to PM2.5 particles and very low levels of green space might have up to 62% increased risk of developing ADHD. On the contrary, children living in greener and less polluted areas have a 50% lower risk of developing the disorder. These are the conclusions of a paper published in Environment International with data from 37,000 children from Vancouver (Canada). The study was led by Matilda van den Bosch, researcher at the Barcelona Institute for Global Health (ISGlobal), a centre supported by the ”la Caixa” Foundation.

The aim of this scientific work was to investigate the possible associations between exposure to greenness, air pollution and noise in early life with later incidence of ADHD, one of the most prevalent neurodevelopmental disorders, which affects up to approximately 5-10% children and adolescents. One of the goals of the study was to evaluate possible joints effects of these exposures in relation to ADHD.

The study used administrative data of births in Metro Vancouver from 2000 to 2001 and retrieved data on ADHD cases from hospital records, physician visits and prescriptions. The percentage of green space in the participants’ neighbourhood was estimated with a novel and precise satellite metric, while the residential levels of two air pollutants —NO2 and PM2.5— as well as noise levels were estimated using available exposure models. Finally, the possible associations between the three environmental exposures and ADHD were assessed using a statistical model that allowed to determine hazard ratios.

The researchers were able to identify 1,217 cases of ADHD, equivalent to a 4.2% of the total study population. The green space analysis revealed that participants living in areas with a greater percentage of vegetation had a lower risk of ADHD. More specifically, the results show that a 12% increase in vegetation percentage was associated with a 10% reduction in the risk of ADHD.

Regarding air pollution, the opposite association was observed with PM2.5: participants with a higher exposure to fine particles had higher risk of ADHD (every 2.1 µg increase in the levels of PM2.5 translated into an 11% increase in the risk of ADHD).

No associations were found for the rest of environmental exposures assessed: NO2 and noise.

Joint effects of PM2.5 and vegetation

The results are consistent with previous studies, which found associations between green space and air pollution, respectively, with ADHD. However, most of the research conducted until now focused on the evaluation of single exposures and rarely evaluated joint effects of multiple environmental exposures.

“We observed that children living in greener neighbourhoods with low air pollution had a substantially decreased risk of ADHD. This is an environmental inequality where, in turn, those children living in areas with higher pollution and less greenness face a disproportionally greater risk”, explains lead author Matilda van den Bosch. “These associations are particularly relevant because exposures take place in early life, a crucial period for brain development where children are especially vulnerable. Importantly, these exposures are modifiable, meaning that the findings should be taken into account for healthier urban planning”, she adds.

“Our findings also show that the associations between PM2.5 and ADHD were attenuated by residential green space and vice versa, as if the beneficial effects of vegetation and the harmful effects of PM2.5 neutralized each other”, says Weiran Yuchi, researcher at the University of British Columbia (Canada) and first author of the study.

Children with higher exposure to air pollutio | EurekAlert!
Posted in Air Quality | Leave a comment

New study identifies link between household air pollution and child pneumonia

Posted on February 23, 2022 by Respro® UK Ltd

A new study published in The Lancet Global Health involving researchers from the University of Liverpool, provides greater understanding of the impact household air pollution can have on the development of child pneumonia.

Streptococcus pneumoniae (the pneumococcus) is a major human pathogen causing more than two million deaths per year; more than HIV/AIDS, measles and malaria combined. It is the leading cause of death due to infectious disease in children under five years of age, but is also part of the normal microbial community of the human upper airways (the nasopharynx). The burden of pneumococcal carriage and pneumonia is particularly high in sub-Saharan Africa.

Household air pollution from solid fuels increases the risk of childhood pneumonia. Nasopharyngeal carriage of Streptococcus pneumoniae is a necessary step in the development of pneumococcal pneumonia. More than 2.6 billion people are exposed to household air pollution worldwide. It is estimated that household air pollution from the burning of biomass and the inefficient use of fuel accounts for approximately 3.8 million premature deaths annually and approximately 45% of all pneumonia deaths in children aged younger than five years. However, there has been little evidence that identifies the causal pathway that links household air pollution and pneumonia.

In order to understand the connection between exposure to household air pollution and the risk of childhood pneumonia researchers from the UK, Malawi and the United States conducted the MSCAPE (Malawi Streptococcus pneumoniae Carriage and Air Pollution Exposure) study embedded in the ongoing CAPS (Child And Pneumonia Study) trial. The MSCAPE study assessed the impact of PM2.5, the single most important health-damaging pollutant in household air pollution, on the prevalence pneumococcal carriage in a large sample of 485 Malawian children.

Through exposure-response analysis, a statistically significant 10% increase in risk of Streptococcus pneumonia carriage in children was observed for a unit increase (deciles) of exposure to PM2.5 (ranging from 3.9 μg/m³ to 617.0 μg/m³).

Dr. Mukesh Dherani, the study principal investigator, indicated: “This study provides us with greater insight into the impact household air pollution can have on the development of child pneumonia. These findings provide important new evidence of intermediary steps in the causal pathway of household air pollution exposure to pneumonia and provide a platform for future mechanistic studies.”

Professor Dan Pope, one of the study authors and Director of the NIHR CLEAN-Air(Africa) Global Health Research Group led by the University of Liverpool stated: “Moving forward further studies, particularly new randomized controlled trials comparing clean fuels (e.g. liquefied petroleum gas) with biomass fuels, with detailed measurements of PM2.5 exposure, and studies of mechanisms underlying increased pneumococcal carriage, are required to strengthen causal evidence for this component of the pathway from household air pollution exposure to ALRI in children.”

Professor Nigel Bruce, co-principal investigator, stated: “This study provides further important evidence that emphasizes the need to accelerate to cleaner fuels, such as LPG, which are now being promoted by many governments across the continent in order to meet SDG7 by 2030.”

New study identifies link between household air pollution and child pneumonia
Posted in Africa, Air Quality, Europe, Health Effects of Air Pollution, Medical Studies, UK, USA, World News | Tagged , , , , , | Leave a comment

Dhaka’s air quality second worst in the world

Posted on February 21, 2022 by Respro® UK Ltd

The densely populated Bangladesh capital Dhaka continues to dominate the list of cities with the worst air quality in the world.

On Monday, Dhaka occupied the second position in the list as its air quality index (AQI) was recorded at 179 at 10.57am.

Pakistan’s Lahore and India’s Kolkata occupied the first and third spots, with AQI scores of 190 and 157, respectively.

An AQI between 101 and 200 is considered ‘unhealthy’, particularly for sensitive groups.

Similarly, an AQI between 201 and 300 is said to be ‘poor’, while a reading of 301 to 400 is considered ‘hazardous’, posing serious health risks to residents.

AQI, an index for reporting daily air quality, is used by government agencies to inform people how clean or polluted the air of a certain city is, and what associated health effects might be a concern for them.

In Bangladesh, the AQI is based on five criteria pollutants — Particulate Matter (PM10 and PM2.5), NO2, CO, SO2 and Ozone.

Dhaka has long been grappling with air pollution issues. Its air quality usually turns unhealthy in winter and improves during the monsoon.

A report by the Department of Environment (DoE) and the World Bank in March 2019 pointed out that the three main sources of air pollution in Dhaka ‘are brick kilns, fumes from vehicles and dust from construction sites’.

With the advent of winter, the city’s air quality starts deteriorating sharply due to the massive discharge of pollutant particles from construction work, rundown roads, brick kilns and other sources.

Air pollution consistently ranks among the top risk factors for death and disability worldwide. Breathing polluted air has long been recognised as increasing a person’s chances of developing a heart disease, chronic respiratory diseases, lung infections and cancer, according to several studies.

As per the World Health Organization, air pollution kills an estimated seven million people worldwide every year, largely as a result of increased mortality from stroke, heart disease, chronic obstructive pulmonary disease, lung cancer and acute respiratory infections.

Dhaka’s air quality second worst in the world
Posted in Air Quality | Leave a comment

Air pollution may affect sperm quality, says study

Posted on February 18, 2022 by Respro® UK Ltd

Research into samples of 30,000 men in China suggests ability of sperm to swim in right direction could be affected

Air pollution may affect semen quality, specifically sperm motility — the ability of sperm to swim in the right direction — according to a new study analysing the sperm of over 30,000 men in China.

The research, published today in the journal JAMA Networks, also suggests that the smaller the size of the polluting particles in the air, the greater the link with poor semen quality.

“Our findings suggest that smaller particulate matter size fractions may be more potent than larger fractions in inducing poor sperm motility,” wrote the authors of the paper. The researchers believe that these findings highlight yet another reason for the need to reduce exposure to air pollution among men in their reproductive age.

Researchers have long been trying to establish whether there’s a link between air pollution and sperm quality, but it’s been unclear whether the former has adverse health effects on male fertility because the results from studies are often inconsistent among themselves and complicated to put into perspective. There does appear to be reason to believe that pollution may negatively affect fertility in general for the whole of the population, as suggested in this international literature review published in December 2021.

Researchers at the School of Medicine of Tongji University in Shanghai looked at data records from a total of 33,876 men from 340 Chinese cities, aged 34 on average, with a varied degree of exposure to air pollution among them, and whose wives got pregnant through assisted reproduction technology with their sperm between January 2013 and December 2019.

They then looked for patterns between semen quality in relation to whether the participants had been exposed to amounts of particulate matter smaller in diameter than 2.5 micrometres, between 2.5 and 10 micrometres, and 10 micrometres, in various key moments of the 90 days before their visit to the hospital for semen ejaculation. To establish the quality of the semen, the researchers concentrated on factors such as sperm count, concentration, and sperm motility.

Although the researchers couldn’t find a significant link between air pollution and sperm quality in terms of sperm count or concentration — they did find that the more a participant was exposed to smaller particulate matter, the lower both the progressive and the total sperm motility was. Progressive sperm motility is the sperm’s ability to swim forward, while total sperm motility simply refers to the sperm’s ability to swim in general.

Specifically, when exposed to particulate matter smaller in diameter than 2.5 micrometres. there was an estimated decrease in sperm motility of 3.6%, while when exposed to particulate matter of 10 micrometres in diameter, there was 2.44% less sperm motility. Meaning that it’s possible that different size fractions of particulate matter might have differing effects on semen quality, maybe because the smaller the particulate matter, the more likely it is to travel deeper into the human lungs.

The data indicates that the effects of pollution are more prominent when exposure takes place during the initial part of the 90 days of sperm creation — the one called spermatogenesis — rather than the other two phases. This, in turn, may mean that particulate matter affects sperm on a genetic level, according to the researchers, but these are just speculations, and there’s more research to be done in this area.

“The possibility of a link between air pollution and semen quality has been suggested in a number of studies over the years, although not all of them have agreed with this conclusion,” said Allan Pacey, professor of andrology at the University of Sheffield, who was not involved in the research. “This paper adds to the evidence base suggesting the link is real, and is impressive because it uses semen quality data from over 30,000 men.”

“But the level of decline in sperm motility seems to be quite low,” said Pacey, stressing that correlation is not causation. He noted that the paper failed to provide any information about the morphology, shape and size of the sperm, which made it impossible to determine whether pollution might be responsible for deformation of sperm and that’s why their motility is decreased, or whether there were other reasons.

According to Pacey, it is important to take these findings with a pinch of salt. Although the data suggests that pollution may have a negative effect on sperm mobility, there still isn’t enough information to infer whether this can have a significant clinical effect at large, and result in the overall decrease of the ability of men in high pollution areas to become fathers. More research out in the field might help answer that question with more certainty in the future.

Air pollution may affect sperm quality, says study | Air pollution | The Guardian
Posted in Air Quality | Leave a comment

Air Pollution May Trigger Psoriasis Flares

Posted on February 17, 2022 by Respro® UK Ltd

A JAMA Dermatology study found that greater exposure to air pollutants, such as carbon monoxide and fine particulate matter, were significantly associated with later psoriasis flares.

Higher exposure to air pollutants may increase the risk of flare and more severe disease in patients with psoriasis, according to study findings published today in JAMA Dermatology.

Characterized by a relapsing-remitting course, psoriasis flares have been noted to be triggered by environmental factors, including infections, stressful life events, and drugs. Moreover, worsening of other diseases that share common inflammatory pathways to psoriasis, such as atopic dermatitis, have been associated with exposure to air pollution.

“After inhalation, pollutants can circulate in the bloodstream, exerting oxidative damage and causing inflammation…air pollutants can directly come into contact with the skin,” said the study authors. “Whether air pollution could trigger psoriasis flares is not known.”

Seeking to investigate whether short-term exposure to environmental air pollution is associated with psoriasis flares, they conducted an observational study, comprised both case-crossover and cross-sectional analyses. They retrospectively analyzed longitudinal data from September 2013 to January 2020 on patients with chronic plaque psoriasis consecutively attending the outpatient dermatologic clinic of the University Hospital of Verona.

Mean and cumulative (area under the curve [AUC]) concentrations of several air pollutants were compared in the 60 days preceding the psoriasis flare and control visits, including for carbon monoxide, nitrogen dioxide, other nitrogen oxides, benzene, coarse particulate matter (PM; 2.5-10.0 mcm in diameter, PM10) and fine PM (< 2.5 mcm in diameter, PM2.5).

Patients recruited for the case-crossover analysis had at least 1 disease flare, defined as Psoriasis Area and Severity Index (PASI) increase of 5 or greater between 2 consecutive assessments in a time frame of 3 to 4 months, whereas patients selected for the cross-sectional analysis included those who received any systemic treatment for 6 or more months, with grade 2 or higher consecutive PASI assessment.

Overall, the study included data on 957 patients with plaque psoriasis with 4398 follow-up visits (mean [SD] age, 61 [15] years; 62.9% male) and more than 15,000 measurements of air pollutant concentrations from the official, open-source bulletin of the Italian Institute for Environmental Protection and Research.

A total of 369 (38.6%) patients with psoriasis flare were included in the case-crossover study and 4072 follow-up visits from 957 patients were used for the cross-sectional analysis.

In findings of the case-crossover study, concentrations of all pollutants (as mean and AUC) were shown to be significantly higher in the 60 days before psoriasis flare (median [interquartile range] PASI, 12 [9-18]), compared with the control visit (median PASI, 1 [1-3); P < .001).

Further sensitivity analyses applying different definitions of psoriasis flare, such as 50% and 100% increases in PASI, indicated that 515 (35.8%) patients had at least a 50% increase and 452 (47.2%) had at least a 100% increase in PASI compared with the control visit, respectively.

Regarding the cross-sectional analysis, exposure to mean PM10 over 20 mcg/m3 and mean PM2.5 over 15 mcg/m3 in the 60 days before assessment were associated with a higher risk of PASI 5 or more points worsening (adjusted OR [aOR], 1.55; 95% CI, 1.21-1.99; aOR, 1.25; 95% CI, 1.0-1.57, respectively). Sensitivity analyses that stratified for trimester of evaluation, with various lag of exposure and adjusting for type of treatment, were found to yield similar results.

“Further study is needed to examine whether these findings generalize to other populations and to better understand the mechanisms by which air pollution may affect psoriasis disease activity,” the concluded researchers.

Biosimilars Available for 3 Drugs Costing More Through Hospitals, Physicians
Posted in Air Quality, Health Effects of Air Pollution, Medical Studies | Tagged , , , , , , | Leave a comment