H5N1

The changing risk and burden of wildfire in the US

Via the National Bureau of Economics: The Changing Risk and Burden of Wildfire in the US. The abstract:

Recent dramatic and deadly increases in global wildfire activity have increased attention on the causes of wildfires, their consequences, and how risk from fire might be mitigated. Here we bring together data on the changing risk and societal burden of wildfire in the US. 

We estimate that nearly 50 million homes are currently in the wildland-urban interface in the US, a number increasing by 1 million houses every 3 years. Using a statistical model that links satellite-based fire and smoke data to pollution monitoring stations, we estimate that wildfires have accounted for up to 25% of PM2.5 in recent years across the US, and up to half in some Western regions. 

We then show that ambient exposure to smoke-based PM2.5 does not follow traditional socioeconomic exposure gradients. Finally, using stylized scenarios, we show that fuels management interventions have large but uncertain impacts on health outcomes, and that future health impacts from climate-change-induced wildfire smoke could approach projected overall increases in temperature-related mortality from climate change. We draw lessons for research and policy.

Air pollution reduction and mortality benefit during the COVID-19 outbreak in China

Via The Lancet Planetary Health: Air pollution reduction and mortality benefit during the COVID-19 outbreak in China. The conclusion, with my bolding:

We found that, because of the quarantine, NO2 dropped by 22·8 μg/m3 in Wuhan and 12·9 μg/m3 in China. PM2·5 dropped by 1·4 μg/m3 in Wuhan but decreased by 18·9 μg/m3 across 367 cities (appendix p 3). The smaller reduction in PM2·5 in Wuhan is due to a similar decreasing trend in PM2·5 in 2016–2019. The pronounced decline in NO2 across China during the quarantine period was also detected by the Copernicus Sentinel-5P satellite with the NO2 tropospheric column density (figure). 

We estimate that improved air quality during the quarantine period avoided a total of 8911 NO2-related deaths (95% CI 6950–10 866), 65% of which were from cardiovascular diseases (hypertensive disease, coronary heart disease, and stroke) and COPD (figure, appendix p 4). Furthermore, we estimate that reduction in PM2·5 during the quarantine period avoided a total of 3214 PM2·5-related deaths (95% CI 2340–4087) in China, 73% of which were from cardiovascular diseases and COPD. Similar estimates were found with an alternative before quarantine period from Jan 1 to Jan 20 (appendix p 3–4). 

Our estimates should be interpreted with caution because of the potential overlap between PM2·5 and NO2-related mortality and the effect on mortality rate from disrupted health-care systems during the quarantine, which could have impacted the timely treatment of patients with chronic diseases. We used cause-specific CRFs from single-pollutant models because coefficients from two-pollutant models were not available. Although there might have been some risk of double counting, results from published literature suggest that this risk is small because effect estimates for NO2 and PM2·5 were similar between single-pollutant and two-pollutant models. Moreover, similar to previous epidemiological studies with outdoor air pollution, exposure measurement error is inevitable since most people stayed indoors. 

Our estimates suggest that interventions to contain the COVID-19 outbreak led to improvements in air quality that brought health benefits in non-COVID-19 deaths, which could potentially have outnumbered the confirmed deaths attributable to COVID-19 in China (4633 deaths as of May 4, 2020). Our findings show the substantial human health benefits related to cardiovascular disease morbidity and mortality that can be achieved when aggressive control measures for air pollution are taken to reduce emissions from vehicles, such as through climate mitigation-related traffic restrictions or efforts to accelerate the transition to electric vehicles.

Air pollution may be ‘key contributor’ to COVID-19 deaths – study

Via The Guardian: Air pollution may be ‘key contributor’ to Covid-19 deaths – study. Excerpt:

High levels of air pollution may be “one of the most important contributors” to deaths from Covid-19, according to research. 

The analysis shows that of the coronavirus deaths across 66 administrative regions in Italy, Spain, France and Germany, 78% of them occurred in just five regions, and these were the most polluted. 

The research examined levels of nitrogen dioxide, a pollutant produced mostly by diesel vehicles, and weather conditions that can prevent dirty air from dispersing away from a city. Many studies have linked NO2 exposure to health damage, and particularly lung disease, which could make people more likely to die if they contract Covid-19. 

“The results indicate that long-term exposure to this pollutant may be one of the most important contributors to fatality caused by the Covid-19 virus in these regions and maybe across the whole world,” said Yaron Ogen, at Martin Luther University Halle-Wittenberg in Germany, who conducted the research. “Poisoning our environment means poisoning our own body, and when it experiences chronic respiratory stress its ability to defend itself from infections is limited.”  

The analysis is only able to show a strong correlation, not a causal link. “It is now necessary to examine whether the presence of an initial inflammatory condition is related to the response of the immune system to the coronavirus,” Ogen said. 

A separate study published on 7 April looked at fine particle pollution in the US and found that even small increases in levels in the years before the pandemic were associated with far higher Covid-19 death rates. Another recent paper noted that the high death rates seen in the north of Italy correlated with the highest levels of air pollution. 

The new research, published in the journal Science of the Total Environment, compared NO2 levels in January and February in 66 administrative regions with Covid-19 deaths recorded up to 19 March. Ogen also assessed the atmospheric conditions to see where pollution was being trapped over the regions. 

He found that 78% of the 4,443 deaths were in four regions in northern Italy and one around Madrid in Spain. These five regions had the worst combination of NO2 levels and airflow conditions that prevented dispersal of air pollution.

Wildfire smoke worsens COVID-19 risk, putting firefighters in extra danger

Via The Conversation, an article by Professor Luke Montrose of Boise State University: Wildfire smoke worsens coronavirus risk, putting firefighters in extra danger. Excerpt:

As summer approaches, two forces of nature are on a collision course, and wildland firefighters will be caught in the middle.  

New research suggests that the smoke firefighters breathe on the front lines of wildfires is putting them at greater risk from the new coronavirus, with potentially lethal effects. 

At the same time, firefighting conditions make precautions such as social distancing and hand-washing difficult, increasing the chance that, once the virus enters a fire camp, it could quickly spread.  

As an environmental toxicologist, I have spent the last decade expanding our understanding of how wood smoke exposure impacts human health. Much of my current research is focused on protecting the long-term health of wildland firefighters and the communities they serve. 

‘Camp crud’ and the dangers of air pollution 

People have long understood that the air they breathe can impact their health, dating back more than 2,000 years to Hippocrates in his treatise on Air, Water, and Places. Today, there is a growing consensus among researchers that air pollution, specifically the very fine particles called PM2.5, influences risk of respiratory illness. These particles are a tiny fraction of the width of a hair and can travel deep into the lungs. 

Italian scientists reported in 2014 that air pollutants can increase the viral load in the lungs and reduce the ability of specialized cells called macrophages to clear out viral invaders. 

Researchers in Montana later connected that effect to wood smoke. They found that animals exposed to wood smoke 24 hours before being exposed to a pathogen ended up with more pathogen in their lungs. The researchers showed that wood smoke exposure decreased the macrophages’ ability to combat respiratory infection. 

Now, new evidence suggests that long-term exposure to PM2.5 air pollution, which is produced by sources such as wildfires, power plants and vehicles, may make coronavirus particularly deadly. 

Researchers from the Harvard T.H. Chan School of Public Health conducted a nationwide study of county-level data and found that even a small increase in the amount of PM2.5 from one U.S. county to the next was associated with a large increase in the death rate from COVID-19. While small increases in PM2.5 also raise the risk of death from other causes for older adults, the magnitude of the increase for COVID-19 was about 20 times greater. The results were released last week, before the usual peer review process was conducted, to help warn people of the risks.

Taken together, these findings suggest that air pollution, including wood smoke, could increase the risk that wildland firefighters will develop severe COVID-19 symptoms.

'It's positively alpine!': Disbelief in big cities as air pollution falls

Via The Guardian, some good news: 'It's positively alpine!': Disbelief in big cities as air pollution falls. The before-and-after photos are, un, breathtaking. Excerpt and then a comment:

The screenshots began to circulate on Delhi WhatsApp groups last week, captioned with varying expressions of disbelief. Having checked the air quality index, something of a sadistic morning ritual among residents of India’s capital, most could not believe their eyes. 

Gone was the familiar menacing red banner, indicating how each intake of breath is really just a toxic blast on the lungs, replaced instead by a healthy, cheerful green. Could it really be that Delhi’s pollution levels now fell into the category of … “good”? “It’s positively alpine!” exclaimed one message.  

A nationwide lockdown imposed across India almost two weeks ago to stop the spread of the coronavirus – the largest lockdown of its kind attempted anywhere – has led to widespread chaos and suffering, especially among the country’s 300 million poor. Yet in Delhi, the world’s most polluted city, it has also resulted in some of the freshest air the capital has seen in decades. 

It is a lockdown silver lining being repeated across the world, as toxic megacities such as Bangkok, Beijing, São Paulo and Bogotá, where varying coronavirus restrictions have been imposed, all reported an unprecedented decline in pollution. Yet it is countered with one cruel irony: with most residents of these cities strictly confined to their homes, few have any way to appreciate this newly fresh air, except through an open window or a during speedy trip to the supermarket. 

In Delhi, air quality index (AQI) levels are usually a severe 200 on a good day (anything above 25 is deemed unsafe by World Health Organization). During peak pollution periods last year they soared well into a life-threatening 900 and sometimes off the measurable scale. But as Delhi’s 11m registered cars were taken off the roads and factories and construction were ground to a halt, AQI levels have regularly fallen below 20. The skies are suddenly a rare, piercing blue. Even the birdsong seems louder.  

Dr Shashi Tharoor, a politician and author who has been vocal on environmental issues, said he hoped that it was a wake-up call. “The blissful sight of blue skies and the joy of breathing clean air provides just the contrast to illustrate what we are doing to ourselves the rest of the time,” said Tharoor. “Today the typical Delhi AQI hovers around 30 and one blissful afternoon, after a spurt of rain, it dropped to 7.” 

“Seven,” Tharoor exclaimed again in disbelief. “In Delhi! Pure joy!”.

But curb your enthusiasm: As of 8:00 p.m. Saturday, local time, Current Delhi AQI is the moderate to unhealthy range.

Air pollution linked to far higher Covid-19 death rates, study finds

Important, but unsurprising. Via The Guardian: Air pollution linked to far higher Covid-19 death rates, study finds. Excerpt:

Air pollution is linked to significantly higher rates of death in people with Covid-19, according to analysis.  

The work shows that even a tiny, single-unit increase in particle pollution levels in the years before the pandemic is associated with a 15% increase in the death rate. The research, done in the US, calculates that slightly cleaner air in Manhattan in the past could have saved hundreds of lives.  

Given the large differences in toxic air levels across countries, the research suggests people in polluted areas are far more likely to die from the coronavirus than those living in cleaner areas. The scientists said dirty air was already known to increase the risk of acute respiratory distress syndrome, which is extremely deadly and a cause of Covid-19-related deaths, as well as other respiratory and heart problems.  

A separate report from scientists in Italy notes that the high death rates seen in the north of the country correlate with the highest levels of air pollution. 

The scientists said their findings could be used to ensure that areas with high levels of air pollution take extra precautions to slow the spread of the virus and deploy extra resources to deal with the outbreak. Air pollution has already fallen because of widespread lockdowns, but the scientists said ensuring cleaner air in the future would help reduce Covid-19 deaths. 

The study, by researchers at the Harvard TH Chan School of Public Health in Boston, analysed air pollution and Covid-19 deaths up to 4 April in 3,000 US counties, covering 98% of the population. “We found that an increase of only 1μg/m3 in PM2.5 [particles] is associated with a 15% increase in the Covid-19 death rate,” the team concluded. 

A small increase in exposure to particle pollution over 15-20 years was already known to increase the risk of death from all causes, but the new work shows this increase is 20 times higher for Covid-19 deaths. 

“The results are statistically significant and robust,” they said. The study took account of a range of factors, including poverty levels, smoking, obesity, and the number of Covid-19 tests and hospital beds available. They also assessed the effect of removing from the analysis both New York City, which has had many cases, and counties with fewer than 10 confirmed Covid-19 cases. 

“Previous work showed that air pollution exposure dramatically increased the risk of death from [the] Sars [coronavirus] during the 2003 outbreak,” said Rachel Nethery, one of the Harvard team. “So we think our results here are consistent with those findings.”

Hubei struggles to handle a mountain of medical waste

Via Sixth Tone: Hubei Struggles to Handle a Mountain of Medical Waste. Excerpt:

In late January, Hubei Zhongyou Youyi EP Technology Co. — a waste treatment company based in the central Chinese city of Xiangyang — received a call from the local authorities. Officials requested the firm to send any workers and vehicles they could spare to Wuhan, the city at the heart of the COVID-19 epidemic, as soon as possible. 

A convoy of five Hubei Zhongyou garbage trucks made the 350-kilometer journey Jan. 29. Their mission was to help transport tons of used face masks, biohazard suits, and bedclothes from Wuhan’s hospitals to disposal sites for destruction.  

At first, the small team of 12 workers and volunteers thought the cleanup job would only take a week. But now, a month later, Hubei Zhongyou has as many as 85 people stationed in Wuhan as the virus-stricken city struggles to deal with unprecedented volumes of contaminated waste.  

The central province of Hubei, where Wuhan is located, has borne the brunt of the epidemic, with over 67,000 people infected and 2,800 killed as of Monday. The crisis has stretched local health systems to their breaking point, forcing the government to build new hospitals from scratch, convert exhibition centers into makeshift wards, and dispatch thousands of medical workers to the region. 

But while attention has been focused on Hubei’s shortage of hospital beds and supplies, cities have also faced severe shortfalls in staff, vehicles, and treatment facilities able to safely dispose of used medical equipment.   

Waste from hospitals has to be dealt with carefully, as it may be infected with harmful microorganisms and could become a secondary source of infection, health experts told Sixth Tone. 

“Protective clothing, surgical gowns, as well as bed sheets and duvet covers used by coronavirus patients — this stuff can’t be reused,” said Yin Kaiwen, head of logistics at a designated clinic for patients infected with COVID-19 based in Wuhan. 

Cities have specialized systems for disposing of medical waste, but they were quickly overwhelmed during the early stages of the epidemic. Before the outbreak began, Wuhan had one dedicated medical waste treatment facility with a processing capacity of 50 tons per day. By Jan. 24, however, the city was producing four times that amount.  

Bags of used equipment piled up in parking lots outside some hospitals in Wuhan due to the backlog at treatment plants and lack of waste transportation vehicles. Nearly 200 tons of additional waste remained inside storage facilities, according to government estimates.  

“The epidemic in Wuhan is the worst in the country,” said Yan Zuhai, deputy head of publicity at Wuhan’s ecology and environment bureau, in a phone interview with Sixth Tone Feb. 26. “Faced with this powerful enemy, the city currently doesn’t have the capacity to handle the (medical) waste.”  

China took emergency measures to deal with the crisis Jan. 28, handing local authorities the power to burn medical waste using nonstandard facilities, set up mobile treatment centers, and transport excess waste to nearby cities for disposal. 

In the weeks since, Wuhan has used incinerators designed for household and hazardous waste, industrial furnaces, and even cement kilns to destroy used medical supplies. It has also enlisted the help of treatment companies in other cities, including Hubei Zhongyou. 

“Wuhan’s medical waste disposal system isn’t designed to cope with an emergency,” said Sun Yu, director of enterprise management at Hubei Zhongyou. “We’re helping them relieve their shortage of transportation and treatment capacity.”

COVID-19 has temporarily reduced China’s CO2 emissions by a quarter

Via Carbon Brief: Analysis: Coronavirus has temporarily reduced China’s CO2 emissions by a quarter. Excerpt:

As China battles one of the most serious virus epidemics of the century, the impacts on the country’s energy demand and emissions are only beginning to be felt.  

Electricity demand and industrial output remain far below their usual levels across a range of indicators, many of which are at their lowest two-week average in several years. These include:  

• Coal use at power stations reporting daily data at a four-year low. 

• Oil refinery operating rates in Shandong province at the lowest level since 2015. 

• Output of key steel product lines at the lowest level for five years. 

• Levels of NO2 air pollution over China down 36% on the same period last year. 

• Domestic flights are down up to 70% compared to last month. 

All told, the measures to contain coronavirus have resulted in reductions of 15% to 40% in output across key industrial sectors. This is likely to have wiped out a quarter or more of the country’s CO2 emissions over the past two weeks, the period when activity would normally have resumed after the Chinese new-year holiday.

Over the same period in 2019, China released around 400m tonnes of CO2 (MtCO2), meaning the virus could have cut global emissions by 100MtCO2 to date. The key question is whether the impacts are sustained, or if they will be offset – or even reversed – by the government response to the crisis. 

Initial analysis from the International Energy Agency (IEA) and Organization of the Petroleum Exporting Countries (OPEC) suggests the repercussions of the outbreak could shave up to half a percent off global oil demand in January-September this year.  

However, the Chinese government’s coming stimulus measures in response to the disruption could outweigh these shorter-term impacts on energy and emissions, as it did after the global financial crisis and the 2015 domestic economic downturn.

Analysis: Coronavirus has temporarily reduced China’s CO2 emissions by a quarter

Via Carbon Brief, an eye-opener: Analysis: Coronavirus has temporarily reduced China’s CO2 emissions by a quarter. Excerpt (but read the whole thing), and then a comment:

As China battles one of the most serious virus epidemics of the century, the impacts on the country’s energy demand and emissions are only beginning to be felt.  

Electricity demand and industrial output remain far below their usual levels across a range of indicators, many of which are at their lowest two-week average in several years. These include:  

• Coal use at power stations reporting daily data at a four-year low. 

• Oil refinery operating rates in Shandong province at the lowest level since 2015. 

• Output of key steel product lines at the lowest level for five years. 

• Levels of NO2 air pollution over China down 36% on the same period last year. 

• Domestic flights are down up to 70% compared to last month. 

All told, the measures to contain coronavirus have resulted in reductions of 15% to 40% in output across key industrial sectors. This is likely to have wiped out a quarter or more of the country’s CO2 emissions over the past two weeks, the period when activity would normally have resumed after the Chinese new-year holiday.  

Over the same period in 2019, China released around 400m tonnes of CO2 (MtCO2), meaning the virus could have cut global emissions by 100MtCO2 to date. The key question is whether the impacts are sustained, or if they will be offset – or even reversed – by the government response to the crisis. 

Initial analysis from the International Energy Agency (IEA) and Organization of the Petroleum Exporting Countries (OPEC) suggests the repercussions of the outbreak could shave up to half a percent off global oil demand in January-September this year.  

However, the Chinese government’s coming stimulus measures in response to the disruption could outweigh these shorter-term impacts on energy and emissions, as it did after the global financial crisis and the 2015 domestic economic downturn.

Regardless, Bejiing's air quality index as of 7:00 a.m. Thursday morning, local time, is in the 170s and 180s (unhealthy).

Coal mines need miners amid COVID-19 travel restrictions

Via Caixin Global: Coal Mines Need Miners Amid Virus Travel Restrictions. Excerpt and then a comment:

China’s coal heartlands are still operating well below their gigantic capacity, government statistics show, even after the official return to work after an extended Lunar New Year holiday due to the coronavirus. 

Ordos, in North China’s Inner Mongolia autonomous region, has 333 coal mines and can produce more of the fossil fuel than any other city in China — 838 million tons a year. But as of Wednesday only 72 mines have resumed operations, representing a little more than two-fifths of the city’s total production capacity, according to the local energy administration.  

The situation in Ordos is replicated throughout the world’s largest coal producing nation. According to China’s top economic planner, the National Development and Reform Commission, only 57.8% of China’s coal mines had resumed work as of Monday, the first official work day after the government lengthened the normally week-long Lunar New Year break to curb the spread of the highly contagious coronavirus. 

 “This is because (coal mines are) short-handed, so they cannot run to full capacity,” said a person familiar with the industry in Northwest China’s Shaanxi province, a major coal mining region. Another coal industry analyst said some mines have had to reassign workers from production to safety-checking due to staffing issues, which has further depressed output.  

Travel restrictions that aim to keep the virus in check after it has infected tens of thousands of people and spread both around the country and world have prevented many miners — who are often migrant workers from other parts of the country — from traveling back to their workplaces after the Lunar New Year holiday. It’s still unclear when these restrictions will be lifted, an industry insider said.

It's some consolation that the outbreak is at least helping reduce CO2 emissions and air pollution.