PM10
Hong Kong enjoys a breath of fresh air but it’s not enough to meet annual quality goals
Lower concentrations of harmful pollutants were recorded last year but roadside-dominant nitrogen dioxide remains a headache for the city
Lower concentrations of harmful pollutants were recorded last year, including the tiny particulates that can penetrate deep into the lungs – but roadside- dominant nitrogen dioxide remains a headache for the city, with most figures failing annual air quality targets.
And while ambient concentrations of hazardous ozone fell for the second consecutive year, they are proving stubbornly hard to cut having increased 15 per cent since 1999.
The preliminary air quality data for 2016 was released by the Environmental Protection Department yesterday.
At roadsides, concentrations of respirable suspended particulates (PM10) dropped by 15 per cent, fine suspended particulates (PM2.5) by 12 per cent, and sulphur dioxide
(SO2) by 10 per cent.
Similar drops were recorded at general stations. Fewer hours and days of high health risk air were recorded at both ambient and roadside stations last year.
But although roadside concentrations of nitrogen dioxide (NO2) – a product of fuel combustion – fell by 17 per cent, the average annual concentration of 82 micrograms per cubic metre of air was still more than double the annual air quality objective target of just 40.
All three roadside monitoring stations also fell short of the air quality objectives for acceptable annual NO2 levels last year.
“Roadside NO2 remains a very big challenge as reduction technologies available now are not that sophisticated,” assistant director of air policy Mok Wai-chuen said.
At roadsides, concentrations of respirable suspended particulates (PM10) dropped by 15 per cent, fine suspended particulates (PM2.5) by 12 per cent, and sulphur dioxide
(SO2) by 10 per cent.
Similar drops were recorded at general stations. Fewer hours and days of high health risk air were recorded at both ambient and roadside stations last year.
But although roadside concentrations of nitrogen dioxide (NO2) – a product of fuel combustion – fell by 17 per cent, the average annual concentration of 82 micrograms per cubic metre of air was still more than double the annual air quality objective target of just 40.
All three roadside monitoring stations also fell short of the air quality objectives for acceptable annual NO2 levels last year.
“Roadside NO2 remains a very big challenge as reduction technologies available now are not that sophisticated,” assistant director of air policy Mok Wai-chuen said.
He believed improvements in particulate pollution were a result of policy measures such as an ongoing scheme to phase out old diesel commercial vehicles progressively and new laws requiring ships at berth to switch to low- sulphur fuel.
“This proves our policies to tackle particulate matter have been effective,” he said, adding that other measures such as tightening emission controls are being looked at.
Mok claimed the most severely polluted days were a result of ozone, a regional problem, either from pollution blowing in from the Pearl River Delta or meteorological
conditions such as tropical cyclones.
Ozone is formed through a reaction of nitrogen oxides (NOx) and volatile organic compounds (VOCs) in the air and under sunlight. It is a main component of photochemical smog – which gives a dusk sky a lurid, orange tint – and at elevated levels, can cause or aggravate respiratory diseases.
Asked if the toxic smog plaguing northern China could have drifted south, he said “it could not be ruled out” but “was of low possibility”.
The Clean Air Network’s Loong Tsz-wai said Mok’s meteorological explanations diverted attention from the most pressing issue, which was roadside pollution and the
“uncontrolled growth” of road vehicles.
“Most of our exposure to bad air is at roadside,” he said. “NO2 concentrations may be going down but the effectiveness of exhaust pipe policies could be easily offset over the years if the number of private cars is not curbed.”
Wang Tao, chair professor of atmospheric environment at Polytechnic University, said the increase in regional ozone had indeed slowed since 2013, but not fallen. More control of precursors, such as VOC and NOX, were needed on both sides of the border, he said.
Source URL: http://www.scmp.com/news/hong-kong/healthenvironment/article/2059691/hong-kong-enjoys-breath-fresh-air-its-not-enough
Something in the air: Is Hong Kong’s pollution problem worsening?
https://www.timeout.com/hong-kong/blog/something-in-the-air-is-hong-kongs-pollution-problem-worsening-092116
The government is trumpeting recent figures that show air pollution is significantly decreasing but is the news as good as it sounds? And what other forms of pollution should Hongkongers worry about?
Christie Tse and Joyce Au find out
“See the people walking by right now? Leisurely walking past, enjoying life, breathing the fresh air?” asks Dr Bob Tsui, vicechairman of NGO Clear The Air, as he points out his office window overlooking the streets of Jordan. You are being ‘attacked through your eyes, your cornea, your nostrils, your mouth and your skin” all the time, he follows up. As you’re reading this, tiny deadly pollution particles called magnetites are slowly moving up your nostrils, penetrating your brain tissue, nervous system and lungs. In a crowded, polluted city like Hong Kong, your body is constantly under attack, every second of every day according to Dr Tsui.
According to government statistics, though, air pollution has been decreasing for several years now. The Environmental Protection Department reckons that between 2011 and 2015, average concentrations of PM10, PM2.5, nitrogen dioxide and sulphur dioxide at roadside monitoring stations fell by 26 percent, 21 percent, 19 percent and 33 percent, respectively. The figures sound impressive and the government has been running adverts on TV trumpeting its success at clearing the air.
However, all is not rosy. Recent studies conducted by scientists in Mexico City have discovered a correlation between 100 and 200 nanometer magnetites released through the exhaust pipes of taxis and buses and the development of Alzheimer’s disease. This new information has sparked concern in the local scientific community since roadside pollution remains one of the leading causes of air pollution in our jam-packed city. “In the past 20 years, Hong Kong has not once met its own Air Quality Index standard or that of the World Health Organisation’s,” exclaims Patrick Fung, CEO of NGO Clean Air Network. Paul Zimmerman, Southern District councillor, believes this is unforgiveable, as ‘it’s almost like violence is around you the whole time’, he tells us.
And that’s not the half of it. You may think you can avoid pollution by simply turning recluse and staying at home, but you’d be very wrong.
Studies conducted at the University of Hong Kong reveal that our own kitchens discharge carcinogenic particles into the air every time food is made with vegetable oil. Dr Tsui states that vegetable oil is ‘the most dangerous oil you can use’ since it contributes to air pollution. Clear The Air has published an article that details the process by which vegetable oil, when subjected to high temperatures, oxidises into cancer causing chemicals. “People wonder how they get sick because they eat well all their lives,” Dr Tsui remarks, “but they don’t realise they’re constantly surrounded by these cancerous particles.”
The worst part of all of this is that the toxic kitchen discharge is completely preventable. According to Dr Tsui, the government has the ability and resources to go into restaurants and check their deep friers for dangerous particles.
“It’s a simple test strip and they can do it very easily,” he tells us. “But I have made this announcement for years and the government has not taken any action!” By placing steam jet filters in the kitchen stove, the carcinogenic particles could be released into water. This wouldn’t contaminate the water, according to Dr Tsui, because by the time the dangerous particles pass through the filter and hit the water, many things happen chemically to make the particles no longer harmful.
And cooking oil and air pollution are not the only worries we need have in Hong Kong. After the waves of rubbish that washed up on our beaches over the summer, Hongkongers should be acutely aware of the problem of landfill. Around 30 percent of landfill is made of Styrofoam and in 500 years, that same Styrofoam will still not have decomposed. What’s worse, Styrofoam is mainly composed of styrene, an extremely dangerous chemical that has been linked to cancer, vision and hearing loss, impaired memory and concentration, damage to the nervous systems and depression. “Styrene is dangerous,” Dr Tsui declares. “Styrene is vicious. Styrene should not exist in the food chain and yet, every restaurant [in Hong Kong] today still uses Styrofoam takeout boxes.” Worryingly, when we eat hot food or drink hot liquid from Styrofoam plates, boxes or cups, it’s possible for us to consume the styrene that leaches out of the hazardous material.
Once we’ve ingested these dangerous chemicals, they can swim into our bloodstreams, penetrate our organs and cause irrevocable damage to our bodies. Even Styrofoam that’s out in the ocean can ultimately affect us since when marine life, such as fish, consume it, styrene enters the food chain and eventually, Dr Tsui believes, ‘we’ll eat the darn thing’.
Dr Tsui asks: “How can the government be so blind and be so idiotic to allow this to go on?” Just as toxic kitchen discharges are preventable, so too is the use of Styrofoam. Not just in the food industry but all industries. Instead of using Styrofoam boxes for takeaway meals, companies should start using biodegradable containers, Clear The Air advocates. This minor innovation is also very much within the grasp of companies’ capabilities. Fibre generated from corn can be made to make the boxes and then coated in honey wax. Best of all, these resources are biodegradable.
Another solution that the government and corporations can consider implementing, according to Clear The Air, is changing the original chemical composition used to make Styrofoam. The government could order corporations to put titanium dioxide polymers in the Styrofoam so that once the material is dumped on landfill or into the ocean and exposed to UV light, the Styrofoam will disintegrate into carbon dioxide and water, which equates to less harmful pollution.
There are many little things we can do to contribute to a more environmentally friendly society, such as switching off the lights when we leave a room, turning off the air conditioner when we leave the house, adding insulated panels to our windows and attaching solar panels to our roofs. The list is endless. But while every little helps, these changes are too-little-too-late because, ultimately, it is up to our local authority to enact the kind of legislative reform required to make a real difference. As Dr Tsui so clearly puts it: “No matter how rich or how poor you are, you are subjected to this kind of invisible attack. The government needs to stop with the [political games] and start working on practical solutions to eradicate pollution-induced cancer.”
Unfortunately, when it comes to asking the government for help, every issue seems like an urgent matter. Compared to global threats such as deadly diseases like the zika virus or even more mundane local issues like affordable housing, the largely invisible problem of pollution is all too often pushed to the bottom of the list of priorities.
The public, not just the government, underestimate the drastic consequences of air contamination since the effects are not as apparent as many other similarly pressing matters. But pollution is an urgent problem because it surrounds us all. It’s in the air we breathe, the places we walk and the supposedly safe confines of our own homes. We live and breathe pollution whether we like it or not, so it’s about time we paid attention.
For more information visit cleartheair.org.hk.
Air pollution causes wrinkles and premature ageing, new research shows
Toxic fumes may be the primary cause of skin ageing in polluted cities such as London, New York and Beijing, scientists say
https://www.theguardian.com/environment/2016/jul/15/air-pollution-causes-wrinkles-and-premature-ageing-new-research-shows
Air pollution is prematurely ageing the faces of city dwellers by accelerating wrinkles and age spots, according to emerging scientific research.
The effects of toxic fumes on skin are being seen in both western cities, such as London and New York, as well as in more visibly polluted Asian cities and in some cases may be the primary cause of ageing. The pollution is also being linked to worsening skin conditions such as eczema and hives.
The scientific discoveries are now driving the world’s biggest cosmetics companies to search for solutions, including medicine-like compounds that directly block the biological damage. But doctors warn that some common skin care routines, such as scrubs, make the damage from air pollution even worse.
Poisonous air is already known to cause millions of early deaths from lung and heart diseases and has been linked to diabetes and mental health problems. But perhaps its most visible impact, the damage caused to skin, is just beginning to be understood.
“With traffic pollution emerging as the single most toxic substance for skin, the dream of perfect skin is over for those living and working in traffic-polluted areas unless they take steps to protect their skin right now,” said Dr Mervyn Patterson, a cosmetic doctor at Woodford Medical clinics in the UK.
“Unless people do more they will end up wearing the pollution on their faces in 10 years’ time. It is definitely something people now need to take seriously.”
Prof Jean Krutmann, director at the Leibniz Research Institute for Environmental Medicine in Germany, said: “UV [damage from the sun] was really the topic in skin protection for the last 20-30 years. Now I think air pollution has the potential to keep us busy for the next few decades.”
Air pollution in urban areas, much of which comes from traffic, includes tiny particles called PMs, nitrogen dioxide (NO2) and chemicals such as polycyclic aromatic hydrocarbons (PAHs). “What is very clear is that PMs are a problem for skin,” said Krutmann, whose work has shown PMs increase age spots and wrinkles.
But one of the his newest studies showed NO2 also increases ageing. They studied people in both Germany and China and discovered that age spots on their cheeks increased by 25% with a relatively small increase in pollution, 10 microgrammes of NO2 per cubic metre. Many parts of the UK have illegally high levels of NO2, with London breaking its annual limit in the first week of 2016, with levels reaching over 200 microgrammes of NO2 per cubic metre.
Krutmann said other factors, such as UV exposure, nutrition and smoking contribute to ageing: “But what we can say is that, at least for the pigment spots on the cheeks, it seems air pollution is the major driver.”
“It is not a problem that is limited to China or India – we have it in Paris, in London, wherever you have larger urban agglomerations you have it,” he said. “In Europe everywhere is so densely populated and the particles are being distributed by the wind, so it is very difficult to escape from the problem.”
The accelerated skin ageing was seen in relatively young people and Patterson said: “If you are seeing these changes in middle age, these are worrying trends.”
Other recent research is summed up in a review paper in the journal Frontiers in Environmental Science, which concluded: “Prolonged or repetitive exposure to high levels of these [air] pollutants may have profound negative effects on the skin.”
Understanding exactly how air pollution causes the skin damage is at an early stage, according to Krutmann: “We are just now dipping into the mechanisms.” But many of the pollutants are known to pass easily through the skin and cause a variety of impacts.
“These agents have a very irritating effect and once they get into the skin, they activate multiple pathways of inflammation,” said Patterson. “Some pathways ignite the melanocytes, which create far too much pigment and end up giving you unwanted sun spots.”
“Other pathways ignite messengers that make blood vessels grow, that’s what results in increased redness and potentially rosacea,” he said. “Also, if you damage skin, it goes into repair mode and excites enzymes which re-adsorb damaged collagen. When you have too much chronic inflammation, these enzymes remove more collagen than your skin can create. This produces skin laxity and that’s where fine lines and wrinkles come in.”
Dr Debra Jaliman, a skin expert based in New York City, says her patients are now worrying about the impact of air pollution on their skin, which she said can cause darkening of the skin and acne-like eruptions, as well as ageing.
“At the moment, there are not many products for prevention [of air pollution damage], however it may be a trend in the coming years as it becomes a much bigger issue,” she said.
Major beauty companies have begun their own research and are launching the first products formulated to battle skin damage from toxic air. Dr Frauke Neuser, senior scientist for Olay, a Procter and Gamble brand, has run studies showing significantly lower skin hydration in people living in polluted areas and lab studies showing that diesel fumes and PMs cause inflammation in skin cells.
Her team then screened for ingredients that could counteract some of the damaging effects. “We found niacinamide – vitamin B3 – to be particularly effective,” she said. “We have recently increased its level in several products by as much as 40%.”
Frauke’s work has also shown direct correlations between spikes in PM air pollution in Beijing and an increase in hospital visits by people with skin conditions including hives. “This indicates that not only skin ageing but also skin health are affected by air pollution,” she said.
L’Oreal, another cosmetics giant, published a medical study in 2015 showing that eczema and hives were more common in people in Mexico exposed to higher levels of air pollution, a conclusion supported by separate research in Canada. “The next step is to understand more deeply the environment-induced damages, in order to develop skin ageing prevention routines and products,” said Dr Steve Shiel, scientific director at L’Oreal.
Clinique, a big makeup brand, has already launched a sonic face cleansing brush it claims better removes pollution. “This [air pollution] is not going to go away. This is not a problem that is easily fixed,” said Janet Pardo at Clinique.
However, researchers are now working on medicine-like compounds that block the damage from air pollution from occurring in the first place. Krutmann’s lab helped Symrise, one of the world’s biggest suppliers of cosmetics ingredients, identify one, though the lab has no commercial stake in the product, which is called SymUrban.
“We found one molecule that can do the job,” he said, and it is now being registered as cosmetic ingredient. “In a few years from now I expect we will see cosmetic products that can specifically protect against skin ageing from air pollution.”
Patterson said it is possible for people to give themselves some protection now. “You don’t have to sit back passively and put up with it. You can take sensible, easy steps that will make a difference.”
“If your skin is really healthy, it is quite a good barrier,” he said, explaining that the top layer is like a roof – flattened cells like tiles separated by protective lipids.
“Certain skin care products are very disruptive to the surface of the skin,” he warned. “So a darling of the industry is retinoids, but these have a very profound negative effect on barrier function. Another darling of the industry is glycolic acid, but it is also very disruptive to the external skin barrier. People think these are good skin care, making the skin look smoother, but they are not helpful for the overall health of the skin barrier.”
Patterson is also dismissive of face scrubs: “The skin is trying its damnedest to make this wonderful defence mechanism and what do women and men do? They scrub the hell out of it. It just doesn’t make sense.” He said products that help repair the skin barrier, by delivering the pre-cursor lipids the cells need, are beneficial, as are ones that tackle inflammation.
“You can also put on a very nice physical shield in the form of good quality mineral makeup,” he said. “That produces an effect like a protective mesh and probably has some trapping effect, protecting against the initial penetration of particles. But you also need always to try to remove that shield in the evening, washing the slate clean every night.”
A New Air Pollution Database Is Good, but Imperfect
WHO’s most recent atlas of air quality leaves significant gaps in coverage
The World Health Organization (WHO) recently released its latest global urban air pollution database, including information for nearly 3,000 cities—a doubling from the 2014 database, which itself had data from 500 more cities than the previous (2011) iteration. These increases in coverage in air pollution measurement and reporting is encouraging, but the WHO numbers reveal that we still have a ways to go to construct a comprehensive and accurate picture of global air quality.
WHO singles out Onitsha, Nigeria and Zabol, Iran as the cities with the world’s worst air pollution, the first for elevated coarse particulate, or PM10, levels and the second for extreme fine particulate, or PM2.5, concentrations.
Yet these dubious rankings come with many uncertainties and stir more questions than they answer. “It is difficult to get accurate measurements in Africa,” a WHO spokeswoman said. “[I]deally the measurements should be done over a year to include different seasons and times of day. The reading in Onitsha may be representative but not altogether reliable.”
The air in Onitsha and Zabol is, in other words, bad, though just how bad we cannot say with certainty. Global air quality is worsening, human exposure to air pollution is on the rise, and deaths caused by these toxins have increased from 4.8 million in 1990 to 5.5 million in 2015. These trends are not, however, represented evenly throughout the world. Developing nations, those experiencing rapid industrial and urban expansion, bear the brunt of air pollution’s pernicious effects. The air in cities like Onitsha and Delhi has worsened as their populations and polluting industries have grown, while New York and London’s air quality has steadily improved.
And yet it is developing cities and nations that are least equipped to monitor and manage their ambient environment. WHO’s latest air quality database underscores this problem, as nations with the most resources have steadily increased air quality monitoring and reporting and have seen their air quality steadily improve. Developing countries have experienced deteriorating air quality alongside economic growth, as measurement in these places lags behind.
The vast majority of ground-based monitors are located in Europe and North America meaning there are major “blindspots” obfuscating where air pollution is affecting the most people in the most pernicious ways. These blindspots are why we need new ways to monitor global air pollution. The 2016 Environmental Performance Index (EPI) reveals the extent to which ground-based air monitoring and reporting is missing areas suffering from some of the world’s worst air pollution. Using satellite data, researchers at Dalhousie University have estimated ground-based exposures to fine particulate pollution or PM2.5—microscopic particles that can penetrate deep into human lung and blood tissue, leading to cardiovascular disease and other serious health impacts.
These satellite data have advantages as well as their disadvantages compared to ground-based information. Satellites offer a globally-consistent, long-term, and dynamic view of air pollution levels, exposures and trends. Satellite data provide a picture of the average PM pollution that an individual living in a particular place would be exposed to on a typical day, potentially smoothing out outlying spikes in air toxin concentrations. These data can be used to gauge pollution’s impacts on human health – in total, Global Burden of Disease estimates outdoor and indoor air pollution is responsible for 5.5 million premature deaths a year. Satellites do not, however, measure air pollution at the ground level, where people live and breathe, which is why governments need to invest in ground-based monitors.
Here we present four visualizations from Data-Driven Yale’s latest research on global air pollution and a fifth graphic from recent studies on pollution sources with original analysis:
1. Nearly half of the world’s people breathes unsafe air, with populations in developing countries disproportionately exposed. One-third (1.3 billion) of these people live in the East Asia and Pacific region, where in China and South Korea more than 50 percent of their populations are exposed to unsafe levels of fine particulate matter. In India and Nepal, the percentage is nearly 75 percent – a figure reinforced by WHO’s 2016 database, showing that 16 of the world’s 30 most polluted cities are in India. In our interactive map areas shaded red or darker experience air pollution that exceeds 10 micrograms/m3 – the threshold WHO considers unsafe for people to breathe. The map shows that East Asia, Northern India, and Northern Africa have the world’s highest levels of fine particulate pollution.
2. Nitrogen dioxide pollution, produced mainly from fossil fuel combustion, is a precursor of ozone and smog and mostly affects Europe and East Asia. In Europe, tax policies dating back to the 1970s and regulations from the 1990s designed to limit tailpipe CO2 emissions have encouraged the production and use of diesel vehicles, resulting in elevated NO2 levels. While diesel vehicles generate 15 percent less CO2 than their gasoline counterparts, diesel engines emit four times more NO2. In London, NO2 pollution is linked to 9,500 deaths annually. These data, derived from satellite estimates, show that air pollution is not only a developing world problem, but that industrialized countries also suffer from foul air. European cities, however, are implementing ambitious policies to reduce air pollution, such as the British capital’s Ultra Low Emissions Zone, which is expected to cut central London’s pollution in half by 2020. Overall air quality has improved in Europe in the last decade, while pollution continues to worsen in most of Asia, Africa, and Latin America.
3. Global monitoring is improving, primarily in developed countries. Figure 3 shows increases in the number of cities monitoring air pollution from the WHO’s 2011, 2014 and 2016 databases. Cities monitoring air pollution have increased in number to the greatest extent in Europe and high-income countries in the Americas in the last five years. Progress in lower to middle-income countries has been much slower.
4. Governments that have implemented policies to control air pollution have reduced deaths. New data released in February of this year as part of the Global Burden of Disease (GDB) project show that 5.5 million premature deaths occur each year due to air pollution. Looking at GBD data over 10 years (Figure 4), key trends emerge. Air pollution-related deaths in Latin America, Sub-Saharan Africa, and Southeast Asia have worsened more dramatically than other regions the last decade. The United States, European Union, and Australia have significantly reduced air pollution-related deaths, largely due to policy interventions targeted at industrial pollution control, reducing fossil fuel consumption, and improving fuel quality in the transport sector.
5. New sources of air pollution detected. Recent studies show that a major contributor to air pollution is shipping. This finding is particularly salient in coastal regions in East Asia. Forty-two percent of Hong Kong’s particulates, for instance, are from the maritime sector. And East Asia has experienced the highest number of shipping-related air pollution deaths. A new study shows that air pollution from the agriculture sector exceeds anthropogenic sources of particulate pollution in the United States and Europe (Figure 5). These studies underscore air pollution’s complex origins, as airborne toxins come from many different sources and activities, both natural and human-driven. The mix of sources makes it ever more challenging to design policies and interventions to address this class of pollutants. Despite the challenges, the imperative is clear: more efforts must be made to reverse the current trends, to reduce human exposure to air pollution and to improve global air quality.
http://blogs.scientificamerican.com/guest-blog/a-new-air-pollution-database-is-good-but-imperfect/
The global air pollution ‘blindspot’ affecting 1 billion people
More than 100 of the world’s poorest and most poorly governed countries have no or limited monitoring of the polluted air their citizens are breathing
https://www.theguardian.com/environment/2016/may/17/the-global-air-pollution-blindspot-affecting-1-billion-people
More than 1 billion people live in countries that do not monitor the air they breathe, according to data released by the World Health Organisation (WHO).
Guardian analysis has revealed a great air pollution blindspot stretching the length of Africa, across large parts of the former Soviet Union, south-east Asia and the Caribbean. In 92 countries the monitoring equipment and staff needed to measure one of the world’s most deadly pollutants – particulate matter (PM) – are simply not available.
A further 33 countries, including Indonesia, Egypt and Russia monitor just one or two cities.
Outdoor air pollution kills 3.3 million people each year and it is getting worse. Globally, pollution levels have risen by 8% in five years. But there are signs that it can be brought under control. According to the WHO, pollution is falling in many places where monitoring occurs, including a third of cities in low- and middle-income countries.
Setting up stations to record pollution was the first step, said a WHO spokeswoman: “The cities which have invested in the capacity to regularly monitor and report the local air quality measurements have already demonstrated a commitment to starting to address air quality issues and public health.”
In those countries with no checks, citizens’ lungs remain the only place where pollution is recorded. People may be acutely aware of the corrupted air, but without the evidence that global or national standards have been breached, there is little imperative for governments to act.
The WHO data, made public last week, showed air pollution was a hallmark of global inequality. Where it is monitored, denizens of poor cities are almost twice as likely as the rich to be breathing bad air.
Poverty is also a common theme. Of the world’s poorest 50 countries by GDP per capita, 35 are not monitoring air in any of their cities. Because they are predominantly poor- to middle-income, unmonitored countries are very likely to have high air pollution in their cities, meaning the majority of city-dwellers in those places will be be unknowingly exposed to pollution that breaches WHO standards.
The cost of setting up a single monitoring station is currently around $150,000-200,000, according to the UN Environment Programme. This does not include the ongoing staffing and maintenance costs. Although new technology may be significantly cheaper.
In Africa, the world’s poorest continent, just 10 out of 54 countries are doing any monitoring at all. Africa has just 1.3% of the cities where the WHO records air quality, despite having 16% of global population and cities set to set to triple in size in the next 50 years.
But it is not only the poor who lack information – the poorly governed also live in the dark. The Economist Intelligence Unit’s (EIU) democracy index labels 51 countries as “authoritarian”. Of these, 36 do not monitor their air. Just five non-monitoring countries appear in the democratic top 50.
In post-Soviet states, most of which rank as middle-income countries, barely any investment has been made in keeping tabs on the air. Across the vast expanse of Russia, with its thousand towns and cities, only Moscow records air quality.
Tiny Latvia boasts more monitoring stations than its former imperial master. Only the three Baltic states – Latvia, Lithuania and Estonia – have managed to implement thorough surveillance. Each of these rates above 7 out of 10 on the EIU index – Russia scores 3.31.
Even in countries where democratic freedom is limited, public information about air pollution can force great change. In China, the public outcry that followed the release of air quality data by the US embassy at Beijing’s forced the Communist party to make air a national priority. The consequent control measures, including a mass shutdown of coal power stations and steelworks, has lead to falling pollution in some of the worst-affected Chinese cities.
The pressure has also encouraged more monitoring. In China, 210 cities are now monitored, compared to 111 just two years before. This fits with an improving trend across the world. In 2014, 1,622 cities were monitored. Now it’s 2,974.
With high costs associated with monitoring, it is necessary to target high-risk areas first. One satellite study found that 96% of west Africans live above the WHO guidelines. However satellite observations are notoriously inexact. Professor Randall Martin is head of the Spartan project, which operates a network of on-ground sites at which satellite measurements can be calibrated.
“Satellite remote sensing offers a global observation source to fill that monitoring gap,” he said.
With these improvements, the blindspot is growing smaller. The number of cities monitored in Africa has doubled, with the notable addition of Nigeria. Africa’s most populous country had no cities being recorded in 2014. Now it has 12, with the city of Onitsha named as the worst city in the world for PM10 (particles under 10 but above 2.5 microns in width) pollution.
Similarly, because of an expansion of monitoring in Iran, the city of Zabol has superseded Delhi as the city with the worst fine particle (PM2.5) pollution.
With hundreds, perhaps thousands, more cities (including Lagos, Nigeria’s largest conurbation) waiting for the fog to be lifted on their own air quality, it is unlikely these two will remain at the top for long.
Air pollution levels rising in many of the world’s poorest cities
http://www.who.int/mediacentre/news/releases/2016/air-pollution-rising/en/
More than 80% of people living in urban areas that monitor air pollution are exposed to air quality levels that exceed WHO limits. While all regions of the world are affected, populations in low-income cities are the most impacted.
According to the latest urban air quality database, 98% of cities in low- and middle income countries with more than 100 000 inhabitants do not meet WHO air quality guidelines. However, in high-income countries, that percentage decreases to 56%.
In the past two years, the database – now covering 3000 cities in 103 countries – has nearly doubled, with more cities measuring air pollution levels and recognizing the associated health impacts.
As urban air quality declines, the risk of stroke, heart disease, lung cancer, and chronic and acute respiratory diseases, including asthma, increases for the people who live in them.
“Air pollution is a major cause of disease and death. It is good news that more cities are stepping up to monitor air quality, so when they take actions to improve it they have a benchmark,” says Dr Flavia Bustreo, WHO Assistant-Director General, Family, Women and Children’s Health. “When dirty air blankets our cities the most vulnerable urban populations—the youngest, oldest and poorest—are the most impacted.”
Global urban air pollution trends
WHO was able to compare a total of 795 cities in 67 countries for levels of small and fine particulate matter (PM10 and PM2.5) during the five-year period, 2008-2013. PM10 and PM2.5 include pollutants such as sulfate, nitrates and black carbon, which penetrate deep into the lungs and into the cardiovascular system, posing the greatest risks to human health. Data was then analysed to develop regional trends.
Key trends from 2008-2013:
- Global urban air pollution levels increased by 8%, despite improvements in some regions.
- In general, urban air pollution levels were lowest in high-income countries, with lower levels most prevalent in Europe, the Americas, and the Western Pacific Region.
- The highest urban air pollution levels were experienced in low-and middle-income countries in WHO’s Eastern Mediterranean and South-East Asia Regions, with annual mean levels often exceeding 5-10 times WHO limits, followed by low-income cities in the Western Pacific Region.
- In the Eastern Mediterranean and South-East Asia Regions and low-income countries in the Western Pacific Region, levels of urban air pollution has increased by more than 5% in more than two-thirds of the cities.
- In the African Region urban air pollution data remains very sparse, however available data revealed particulate matter (PM) levels above the median. The database now contains PM measurements for more than twice as many cities than previous versions.
Reducing the toll on human health
Ambient air pollution, made of high concentrations of small and fine particulate matter, is the greatest environmental risk to health—causing more than 3 million premature deaths worldwide every year.
“Urban air pollution continues to rise at an alarming rate, wreaking havoc on human health,” says Dr Maria Neira, WHO Director, Department of Public Health, Environmental and Social Determinants of Health. “At the same time, awareness is rising and more cities are monitoring their air quality. When air quality improves, global respiratory and cardiovascular-related illnesses decrease.”
Most sources of urban outdoor air pollution are well beyond the control of individuals and demand action by cities, as well as national and international policymakers to promote cleaner transport, more efficient energy production and waste management.
More than half of the monitored cities in high-income countries and more than one-third in low- and middle-income countries reduced their air pollution levels by more than 5% in five years.
Reducing industrial smokestack emissions, increasing use of renewable power sources, like solar and wind, and prioritizing rapid transit, walking and cycling networks in cities are among the suite of available and affordable strategies.
“It is crucial for city and national governments to make urban air quality a health and development priority,” says WHO’s Dr Carlos Dora. “When air quality improves, health costs from air pollution-related diseases shrink, worker productivity expands and life expectancy grows. Reducing air pollution also brings an added climate bonus, which can become a part of countries’ commitments to the climate treaty.”
During the World Health Assembly, 23-28 May, Member States will discuss a road map for an enhanced global response to the adverse health effects of air pollution.
WHO’s Air quality guidelines offer global guidance on thresholds and limits for key air pollutants that pose health risks. The Guidelines indicate that by reducing particulate matter (PM10) pollution from 70 to 20 micrograms per cubic metre (μg/m), air pollution-related deaths could be reduced by roughly 15%.
Notes to editors:
The WHO urban air quality database builds on well-established, public air quality monitoring systems as a source of reliable data in different parts of the world. National efforts to create operational and representative air quality monitoring systems should be strongly encouraged and supported.
The primary source of data include official reporting from countries to WHO, and official national and sub-national reports and web sites containing measurements of PM10 or PM2.5. Measurements reported by the following regional networks were used: the Clean Air Asia for Asia and the European Environment Agency for Europe’s Air Quality e-Reporting database. In the absence of data from the previous sources, data from UN and development agencies, peer-reviewed journal articles and ground measurements compiled in the framework of the Global Burden of Disease project were used.
Annual mean concentrations of particulate matter (PM10 and/or PM2.5) based on daily measurements, or data which could be aggregated into annual means, were included in the database. In the absence of annual means measurements covering a more limited period of the year were exceptionally used.
WHO Ambient Air Quality Guidelines
PM2.5
10 μg/m3 annual mean
25 μg/m3 24-hour mean
PM10
20 μg/m3 annual mean
50 μg/m3 24-hour mean
For more information, please contact:
Nada Osseiran
WHO Department of Public Health, Environmental and Social Determinants of Health
Telephone: +41 22 791 4475
Mobile: +41 79 445 1624
Email: osseirann@who.int
Kimberly Chriscaden
WHO Department of Communications
Telephone: +41 22 791 2885
Mobile : +41 79 603 1891
Email: chriscadenk@who.int
许多世界最贫困城市的空气污染水平上升
新闻稿
2016年5月12日 | 日内瓦 – 全球80%以上生活在监测空气质量的城市的人,呼吸着质量超出世卫组织限值的空气。虽然全世界所有区域都受到影响,但是低收入国家的人口受影响最大。
根据最新的城市空气质量数据库,低收入和中等收入国家中人口超过10万的城市,有98%不符合世卫组织空气质量指南。但是,在高收入国家,该比例为56%。
过去两年间,随着更多城市开始测量空气污染水平并认识到相关健康影响,数据库规模几乎翻了一番,现在覆盖103个国家的3000多个城市。
随着城市空气质量下降,这些城市居民也就面临更大的罹患脑卒中、心脏病、肺癌以及包括哮喘在内的急慢性呼吸道疾病的风险。
世卫组织家庭、妇女和儿童卫生事务助理总干事Flavia Bustreo博士说:“空气污染是造成疾病和死亡的一个主要原因。好消息是更多城市正在加紧监测空气质量,这样在采取行动改善空气质量的时候,它们就有了可以参照的标准。当肮脏的空气像毯子一样裹住我们的城市,最弱势的城市人群受影响最大,也就是最年轻、最年老和最贫困的人。”
全球空气污染趋势
世卫组织在2008-2013年五年时间内比较了67个国家总计795个城市的颗粒物(PM10)和细颗粒物(PM2.5)水平。颗粒物和细颗粒物包括硫酸盐、硝酸银和黑炭等污染物,它们可以深入肺部和心血管系统,给人类健康带来极大风险。随后对数据进行了分析,以了解区域趋势。
2008-2013年的重要趋势:
虽然一些区域有所改善,但全球城市空气污染水平上升了8%。
总体而言,城市空气污染水平在高收入国家是最低的,大部分较低的污染水平出现在欧洲、美洲和西太平洋区域。
城市空气污染水平最高的地方是世卫组织东地中海区域和东南亚区域的低收入和中等收入国家,年平均水平往往超过世卫组织限值的5-10倍;紧随其后的是西太平洋区域的低收入城市。
在东地中海区域和东南亚区域,以及西太平洋区域的低收入国家,三分之二以上城市的空气污染水平上升了5%以上。
非洲区域的城市空气污染数据仍然很少,但是可获得数据显示颗粒物和细颗粒物水平高于中位数。现在,数据库的颗粒物和细颗粒物测量涵盖的城市数量是之前版本的两倍还多。
降低对人类健康的影响
高浓度的颗粒物和细颗粒物造成的周边环境污染是健康面临的最大环境风险,在全世界每年导致三百多万人过早死亡。
世卫组织公共卫生、环境和健康问题社会决定因素司司长Maria Neira博士说:“城市空气污染继续以惊人的速度增加,严重破坏人类健康。同时,人们的意识也在提示,更多城市正在监测空气质量。空气质量改善,全球呼吸道和心血管相关疾病就相应减少。”
城市室外空气污染的大部分来源是个人无法控制的,需要城市采取行动,也需要国家和国际决策者促进更清洁的交通以及更高效的能源生产和废物管理。
高收入国家半数以上及低收入和中等收入国家三分之一以上开展监测的城市,在五年间将空气污染水平降低了5%以上。
现有可负担策略包括减少工业烟囱排放、增加使用太阳能和风能等可再生电力来源以及在城市中重点发展快速公交、步行和骑行网络。
世卫组织的Carlos Dora博士说:“城市和国家政府使空气质量成为卫生和发展重点至关重要。空气质量改进时,与空气污染有关的疾病导致的卫生费用就会减少,工人的劳动生产率提高,预期寿命延长。减少空气污染还会带来额外的气候红利,这可以是各国对气候条约承诺的一部分。”
5月23-28日世界卫生大会期间,会员国将讨论加强全球应对空气污染的不良健康影响的路线图。
世卫组织的空气质量指南为构成健康风险的重要空气污染物的阈值和限值提供全球指导。该指南支出,将颗粒物污染从每立方米70微克降到20微克,空气污染相关死亡可能减少约15%。
世卫组织城市空气质量数据库以全世界各地信誉卓著的公立空气质量监测系统为基础和可靠数据源。应强烈鼓励和支持各国努力建立并运行有代表性的空气质量监测系统。
给编辑的说明:
世卫组织查收空气质量数据库覆盖三千多个人类居住区,其人口规模从几百人到九百余万不等。大部分数据来自有五万或以上人口的城市。但是,约25%数据来自居民数量不超过两万的较小城市地区。
主要数据来源包括各国向世卫组织提交的官方报告、国家和次国家级正式报告以及包含颗粒物或细颗粒物测量结果的网站。还使用了以下区域网络报告的测量结果:亚洲清洁空气中心报告的亚洲数据和欧洲环境局向欧洲空气质量电子报告数据库报告的数据。在缺乏上述来源数据的情况下,使用了来自联合国和发展伙伴、经过同行评议的期刊文章和全球疾病负担项目框架下汇编的实地测量结果数据。
数据库内容包括根据每日测量结果计算的颗粒物和细颗粒物年度平均浓度或者可以被总和为年度平均值的数据。在没有年度平均值的情况下,作为例外使用了覆盖一年之内较有限时间段的测量结果。
世卫组织环境空气质量指南
PM2.5
年平均值:10微克/立方米
24小时平均值:25微克/立方米
PM10
年平均值:20微克/立方米
24小时平均值:50微克/立方米
欲获更多情况,请联络:
世卫组织公共卫生、环境和健康问题社会决定因素司
Nada Osseiran
电话:+41 22 791 4475
手机:+41 79 445 1624
电子邮件:osseirann@who.int
世卫组织通讯联络司
Kimberly Chriscaden
电话:+41 22 791 2885
手机:+41 79 603 1891
电子邮件:chriscadenk@who.int