Qualité de l’air à North Carolina

Is North Carolina a state with high pollution levels?

North Carolina is a state in the South-eastern region of the United States. It shares land borders with four other states, Tennessee, Virginia, South Carolina and Georgia. It also has a large Atlantic Ocean coastline. Raleigh is the state capital but Charlotte is the largest city. The state population in 2019 was almost 10.5 million people, which ranked it as the 9^th most populous state in the US.

Looking at figures from 2020 for the state capital, it can be seen that for 8 months of the year, the air quality in North Carolina was within the target figure set by the World Health Organisation (WHO). The target figure is 10 µg/m³ or less. During March, July and August, the figure rose slightly to between 10 and 12 µg/m³ which put it in the “Good” category. December’s figure showed a small increase which was enough to place it into the next category of “Moderate” with figures between 12.1 and 35.4 µg/m³.

Looking back at figures from previous years, 2017 saw data of 8.7 µg/m³, 2018 returned 8.3 µg/m³. 2019 saw an unexpected spike in the figure which was 12.2 µg/m³, before dropping again in 2020 to 9.5 µg/m³.

This was possibly due to the reduction in movement due to the COVID-19 pandemic.

How is the air quality in North Carolina measured?

Back in the 1970s, there were 6 main pollutants that were identified as being the most detrimental to the environment and to human health. These 6 pollutants are still used as the benchmark today. They are ozone (O₃), particulate matter (PM2.5 and PM10), carbon monoxide (CO), sulphur dioxide (SO₂), nitrogen dioxide (NO₂) and lead (Pb). These six pollutants can cause serious health problems (including premature mortality) and damage the environment and property. Common sources of these pollutants are coal-fired power stations, industrial manufacturing sources and on-road and off-road vehicles.

What are the sources of air pollution in North Carolina?

The two biggest air quality problems in North Carolina are ground-level ozone (the main ingredient in "smog") and particle pollution PM2.5 and PM10. Both pollutants are caused chiefly by emissions from vehicles and from the coal-burning power stations that produce electricity. Even with cleaner cars and other new technology, the air could get worse as the population grows, endangering health and reducing the quality of life.

On a more unusual note, due to the expansion of intensive pig, chicken, and turkey operations, North Carolina now has more tons of manure per acre of farmland than any other state.

Due to the intense nature of “factory-farming”, there is often too much waste produced to be managed safely. It is estimated that 10 billion gallons are produced annually through pig farming. This slurry is kept in cess-pits until it is sprayed onto farmland as fertiliser. However, due to the scale of production now, there is more produced than can be absorbed by the land.

It is estimated that North Carolina is home to 9 million pigs, 776,000 head of cattle, 161 million chickens and 16 million turkeys. The total waste produced by these animals/birds is around 147.5 million pounds of manure, each day. This is more than can be dealt with effectively.

Ammonia is emitted from animal waste products which is a gaseous type of nitrogen. Through leaching into the ground, it pollutes the water and creates dead areas in waterways where no life can exist. It also exacerbates asthma in humans.

Can the quality of air in North Carolina be improved?

In 2019 it was stated that the air quality in North Carolina was indeed improving. It is now cleaner than it was not only since the 1970s but also over the past few years, bringing a bonus to public health and welfare, the environment, mitigating climate change and even uplifting the economy. The Director of North Carolina Division of Air Quality went on to say that ozone and fine particulate matter used to be at the forefront, and extremely complex and difficult issues in the mid-to-late-90s and early 2000s. Since then 100 million pounds of toxic material has been removed from the atmosphere. This can be attributed to several factors such as alliances with various environmental groups and a stricter adherence to the 1970 Clean Air Act. Pollution has been reduced from power stations and from vehicles due to new legislation. Lower prices for natural gas has also helped it to become more popular.

Levels of carbon monoxide (CO), which is mainly produced through the burning of fossil fuels, have dropped to 86 per cent below the national standard since monitoring began in the late 1960s. This is mainly due to improvements in motor vehicle fuel combustion and other advanced technologies.

What can be done to lessen the risk of poor air quality in North Carolina?

• Check daily online air pollution forecasts in your local area. The colour-coded forecasts can let you know when the air is unhealthy in your community.
• Avoid exercising outdoors when pollution levels are high. Limit the amount of time your child spends playing outdoors if the air quality is unhealthy. Children’s lungs are still growing and are more susceptible to polluted air. Due to their height, they are often closer to higher concentrations than adults.
• Always avoid exercising near high-traffic areas. Even when air quality forecasts are green, the vehicles on busy highways can create high pollution levels up to one-third of a mile away. It is, therefore, best to exercise in parks and open spaces, well away from busy roads.
• Use less energy in the home and at the workplace. Generating electricity and other sources of energy creates air pollution.
• Encourage your child’s school to reduce exposure to school bus emissions. To keep exhaust levels down, schools should not allow school buses (and cars) to idle outside of their buildings.

Is North Carolina adopting stricter air pollution standards?

In April 2020, the Environmental Protection Agency approved a proposal that would retain federal air quality standards for particulate matter at current levels. Ordinary people might not think twice about this, but medically trained professionals were extremely disappointed. By continuing to use the old standards and not introduce more stringent ones will mean the difference between life and death for some sufferers. For many years, the accepted figure has been 12 µg/m³ (microns per cubic metre) but it was hoped to begin to reduce this figure bi-annually. Reduce it to 10 µg/m³, then eventually to 8 µg/m³.

As many as 50,000 Americans a year die prematurely from inhaling unhealthy air containing tiny particles and liquid droplets of acids, organic chemicals, metals, dust and other components. Research from the EPA shows that more than 20 million people in the United States live in areas with high levels of fine airborne particles. Exposure to excessive concentrations of particulate matter can affect the lungs and the heart. According to the EPA, particulates can contribute to premature death, heart attacks, irregular heartbeat, aggravated asthma, decreased lung function and increased respiratory problems.

What are the consequences of breathing in polluted air in North Carolina?

Air pollution can cause illness in otherwise healthy people. It is responsible for a half-million missed workdays each year, and millions of cases where North Carolinians experience symptoms such as shortness of breath or a runny nose.

Air pollution leads to an estimated 6,000 hospital admissions for respiratory disease and 2,000 admissions for the cardiovascular disease each year.

Additionally, it can cause approximately 1,500 new cases of asthma and 2,500 new cases of chronic bronchitis in adults on an annual basis. Amongst asthmatics, soot pollution causes an estimated 200,000 asthma attacks annually, with an additional 200,000 caused by smog.

When compared to national statistics, air pollution ranks as the third-highest cause behind premature death, after smoking and poor diet/physical inactivity.

Every year, toxic air pollution causes numerous infant deaths and thousands of school absences due to illness.

When is the air pollution at its worst in North Carolina?

Usually from the beginning of March until the end of October is regarded as “The Ozone Season”. From 2020, the measuring started to take place from a central division. The county-based forecast system replaced the old regional system in order to simplify the information and make it readily available in as short a timeframe as possible. The new process will continue to monitor and forecast ozone and particulate matter, or PM2.5, via the air quality index (AQI), along with the corresponding AQI colour codes to help North Carolinians plan their outdoor activities.

Ozone is a colourless gas that occurs naturally in the Earth’s stratosphere, where it helps protect us from harmful ultraviolet rays. At ground level, however, ozone is a dangerous pollutant that causes a type of “sunburn” inside the lungs, triggering inflammation and making it painful to breathe.

Ozone forms in the air when nitrogen oxides (NOx) react with hydrocarbons on warm, sunny days with little wind. While it was once North Carolina's most widespread air quality concern and contributor to breathing problems, ozone continues to decline due to continual reductions in emissions from its primary air pollution sources: power plants, industry and motor vehicles.