Qualité de l’air à Luoyang

What is the current level of air pollution in Luoyang?

Luoyang is a city located in the central plain at the confluence of the Luo River and Yellow River in the west of Henan province, China. It is one of the Four Great Ancient Capitals of China. A census conducted in 2018 estimated that the population was approximately 6,888,500 inhabitants with 2,178,500 people living in the metropolitan area.

In the first half of 2021, Luoyang was experiencing a period of “Moderate” quality air with a US AQI reading of 78. This United States Air Quality Index figure is recognised by the World Health Organisation and is used as a benchmark figure when comparing other cities.

In order to establish this figure, several of the most common pollutants are measured as a common guide. The concentration levels of the five most common pollutants were measured and recorded. The results were as follows: PM2.5 - 25 µg/m³, PM10 - 31 µg/m³, ozone (O₃) - 130 µg/m³, sulphur dioxide (SO₂) - 9 µg/m³ and carbon monoxide (CO) - 500 µg/m³. The figures are stated as microns/micrograms per cubic metre.

With levels of pollution as relatively high as these, the advice given would be to close doors and windows to prevent the ingress of further dirty air and those people of a sensitive disposition should avoid venturing outside until the air quality improves. The table at the top of this page will help inform you as to when it is safe to do so.

Is the level of air pollution the same all year round in Luoyang?

Air pollution is very volatile and can change quickly due to many variables. It can change over the course of a few hours depending on the prevailing winds and weather conditions.

The figures for 2020 have just been published by the Swiss company IQAir.com and by studying them it can be seen that the seasons of the year play a large part in determining the air quality. During the warmer summer months from May until the end of August, Luoyang experienced “Moderate” quality air with figures between 12.1 and 35.4 µg/m³. The months in springtime of March and April put Luoyang into the “Unhealthy for sensitive groups” classification with figures of 49 and 39.7 µg/m³, respectively. A similar situation occurred during the autumn months of September and October with readings of 35.7 and 54.3 µg/m³, respectively. The remaining winter months of November through to the end of February was the worst period of air quality when it was classed as being “Unhealthy” with figures between 55.5 and 150.4 µg/m³.

Records were first kept in 2017 when the mean annual reading was 72.5 µg/m³. A marked improvement was seen the following year when the recorded figure was seen to be 59.9 µg/m³. A slight rise in 2019 put the figure to 62.4 µg/m³, whilst in 2020 a noticeable drop was recorded with a figure of 50.7 µg/m³. This could be artificially lower because of the restrictions imposed due to the COVID-19 pandemic which restricted the movement of private vehicles and suspended some industrial activity.

Where does all this polluted air in Luoyang come from?

According to information provided by the Luoyang Municipal Environmental Bureau, the primary pollutant in the air in the city is inhalable particulate matter. The second pollutant is sulphur dioxide, with an exceeding rate of about 20 per cent and an upward trend. Nitrogen oxides can basically meet ambient air quality standards, but they are on the rise, and the main source is motor vehicle exhaust fumes.

According to the environmental protection department, the number one source of pollution affecting the ambient air quality in Luoyang is industrial pollution. According to statistics, there are 327 air pollution enterprises in the urban area of Luoyang, 78 coal (heavy oil) industrial kilns, 536 large and small coal-fired boilers, and more than 500 high and low chimneys. These pollution sources emit 30,000 tons of smoke and dust and 40,000 tons of sulphur dioxide into the air every year.

There are more than 50 small forgings, small foundries, small smelters and 161 hand-burning furnaces distributed in the urban area and surrounding areas. None of them has effective dust removal and desulphurisation measures. The boilers and kilns in the urban area have no effective sulphur dioxide treatment facilities either, which is the primary reason for the continuous increase of urban sulphur dioxide emissions and excessive air sulphur dioxide.

The second-largest source of pollution is secondary dust and the third-largest is motor vehicle exhaust fumes. Construction dust pollution generated during the construction process is serious, construction and transportation vehicles carry mud and soil on the road, and a construction site pollutes several roads.

What can be done to alleviate the poor air quality in Luoyang?

Several industries were previously immune to inspection because they were considered to be special cases. This now has stopped and all industrial premises are governed by the same laws. A polluting reporting scheme was introduced where residents who saw law-breakers could report them to the local authorities.

The third is to take specific measures to curb air pollution. Amongst new measures include the banning of the existing 161 hand-fired coal-fired boilers in the urban area and demolish the coal-fired (heavy oil) boilers of 37 companies in the urban area covered by central heating and coal gas with less than 10 tons per hour. For existing coal-fired boilers that are allowed to remain, high-efficiency desulphurisation facilities must be established within the year, and total pollutant discharge control must be implemented.

The Municipal Public Security Bureau enforces a strict vehicle scrapping system, and at the same time, controls exhaust pollution in a multi-faceted manner through various measures such as the exhaust management of in-use vehicles, the use of clean fuels, and the control of oil quality.

What effect does polluted air have on human health?

Air pollution has many potential health effects, ranging from subtle physiological changes in the body to obvious symptoms such as itchy nose and throat, wheezing, coughing, chest pain or chest tightness. Patients with asthma or chronic respiratory diseases will get worse if they are exposed to air pollutants. Although the degree to which different people are affected by air pollution depends on different factors, people of different ages are all affected by poor air quality, and air pollution has a greater impact on children and the elderly.