Some pollutants are responsible for destroying the ozone layer located between 20km and 40km above the earth’s surface.This layer is very important for all life on earth as it blocks harmful radiation from the sun from reaching the earth’s surface. As the ozone layer is being depleted, the harmful radiation could easily reach the earth’s surface. The radiation can decrease plant growth and affect the aquatic life. Production of primary crops, such as rice, corn and sunflower can also be affected.

Human activities are also contributing to the increase of greenhouse gases in the atmosphere, such as carbon dioxide and methane. The build-up of these gases acts like a blanket that traps heat close to the earth’s surface, increasing the temperature, and thus warming the earth. This disrupts the natural greenhouse effect.

What are the effects of air pollution?

Ozone depletion

Global warming

What is the government doing to address air pollution?

Ambient air quality standards:These standards are used to measure if the air is safe for human health. There are standards for major pollutants such as sulphur dioxide, carbon monoxide, lead, nitrogen dioxide, particulate matter and benzene. If the levels of pollution are higher than the levels set in the standards, the air is considered unsafe. This means that the air pollution level poses a health risk to humans and to the environment.

Air Quality Monitoring: In order to manage air quality, it is important to understand what pollutants are present in the atmosphere and at what levels. This can be achieved by ambient air quality monitoring. Special instruments are used to measure the amount of different pollutants in the air. Each pollutant is measured by a specific instrument, and these instruments are housed in a monitoring station. Usually there are several instruments, for example an instrument to measure sulphur dioxide, another for carbon monoxide and so on. Currently there are over a hundred monitoring stations across South Africa. These stations belong to the national, provincial, district, local and metropolitan departments responsible for air quality management. Some industries and other private organisations also have their own monitoring stations. Most of these stations measure pollutants such as sulphur dioxide (SO2

), carbon monoxide (CO), nitrogen dioxide (NO2

), particulate matter (PM10

), lead (Pb), benzene (C6

H6) an ozone (O

3).

National Priority Areas:The government has identif ied air pollution ‘hot spots’ across the country that require special attention due

to the high levels of air pollution. To date there are three priority areas, Vaal Triangle Airshed which includes parts of Free State and Gauteng provinces, Highveld

(parts of Gauteng and Mpumalanga Provinces) and Waterberg-Bojanala (parts of Limpopo and North West

provinces) priority areas. The air quality management plans for these areas were developed and are being implemented to

try and improve air p pollution to acceptable levels.

Section 24 of the Republic of South Africa’s Constitution provides that:• Everyone has the right to an environment that is not harmful to their health or well-being. • The environment is protected for the benefit of present and future generations.

National Environmental Management: Air Quality Act is important as it helps the government to: • Regulate and manage air pollution in the country.• Monitor the pollutants to ensure that air quality is improved.• Enhance the quality of ambient air in order to secure an environment that is not harmful to the health and wellbeing of people.

Setting air quality standardsEmission standards:

The government has published a list of sources/activities which have significant effects on the environment. These sources require an atmospheric emission license before they can operate. From these sources, the government sets limits on the amount of emission a source is allowed to release into the atmosphere. There are emission standards for different industries. It is an offence for industry to emit more than its emission limit. Environmental management inspectors conduct compliance and monitoring to ensure that emission standards are met.

The Air Quality Act (Act No.39 of 2004) defines air pollution as any change in the composition of the air caused by smoke, soot, dust (including fly ash), cinders, solid par ticles of any kind, gases, fumes, aerosols and odorous substances. The substances that cause air pollution are called pollutants. Pollutants that are released directly by sources into our atmosphere are called primary air pollutants. Examples include carbon monoxide from vehicle exhausts and sulphur dioxide from the burning of coal. When primary pollutants react with each other and with other gases in the atmosphere secondary air pollutants, such as ground level ozone, are formed. This is the “bad”ozone found close to the earth’s surface and should not be confused with the “good”ozone that provides us with protection from the harmful ultraviolet radiation. Air pollutants can be gases, like carbon monoxide, sulphur dioxide, oxides of nitrogen and chemical vapours or very small particles, like dust, bacteria, viruses, plant materials, dead skin cells or pieces of hair.

What is air pollution

The air around usWhen we breathe, we take-up oxygen through our lungs and breathe out carbon dioxide. Plants take up carbon dioxide and release oxygen into the atmosphere. Nitrogen is also needed by living organisms. It is soaked into soils, where bacteria use it to make food for plants. The water and gases in the atmosphere allow sun rays to reach the earth’s surface, while trapping the radiation released by the earth. The trapping of radiation, known as natural greenhouse effect, makes the layer of the atmosphere close to the earth surface warm enough to support life on earth.

Health effects

Breathing polluted air can make one’s nose burn, irritate the throat making breathing difficult or can irritate the eyes. This is a typical experience when one is cooking using wood, coal or paraffin.

Tiny particles of dust and smoke can get deep into a person’s lungs and causes problems like wheezing and coughing, especially to those people living with respiratory diseases.

Some people are allergic to air pollutants (e.g. pollen, dust) especially during springtime and suffer from respiratory illnesses such as sinusitis and hay fever

Other health problems related to air pollution include asthma, cancer, heart diseases, skin irritations, headaches, dizziness, fatigue, stress, nervous disorders and birth defects..

When sulphur dioxide and nitrogen oxide gases come in contact with clouds in the atmosphere, these gases can make rain to be more acidic. This acid can be deposited in the form of snow, fog or rain, with serious effects on the environment.

Acid rain contaminates drinking water, damages buildings by corroding cement and causes metals to rust. It poisons soils, affects plant growth, and destroys plant leaves. It also harms animals, aquatic life, and other wildlife.

What are the effects of air pollution?In addition to man-made sources, large quantities of air pollutants are also released from natural sources. These sources include:

What are the sources of air pollution?

Acid rain

Veld fires are common man-made and natural sources to air pollution. They spread very quickly and release pollutants such as carbon monoxide, nitrogen oxide, sulphur dioxide and tiny particles into the atmosphere.

Biological sources: There are significant quantities of pollutants that are released from natural sources such as animals, marshes and the soil. Other pollutants include pollen grains.

Wind erosion: Dust particles are released from soil surfaces during strong winds, especially where there are few plants and the soils are dry e.g in deserts.

Volcanic irruptions produce gases such as carbon dioxide, sulphur dioxide, hydrogen fluoride and ash particles. These eruptions release the pollutants high into the atmosphere, where they can travel long distances causing major disruptions.

Industrial plants that produce metals such as aluminium and steel, refine petroleum, cement or make other chemicals are among those that can produce harmful pollutants. The construction industry is a major source of dust.

Power stations and refineries that produce energy by burning fossil fuels like coal, gas and oil, can emit sulphur dioxide, nitrogen dioxide and tiny particles such as ash.

Mining: Dust particles are produced from mine dumps, ore handling, drilling and blasting and from mine vehicle traffic travelling on unpaved roads. Blasting operations and unplanned burning of coal dumps also release gases such as nitrogen dioxide and sulphur dioxide.

Traffic: Vehicles and aeroplanes also contribute to air pollution. Exhaust fumes from engines contain a number of pollutants, including carbon monoxide nitrogen oxides, and other compounds.

Agricultural activities: Dust particles are produced during ploughing and harvesting activities. The use of chemicals (e.g. fertilizers, pesticides and herbicides) on crops to increase crop quality also contributes to air pollution. Large-scale burning to clear agricultural fields also adds significantly to air pollution.

Household cooking and heating especially when using coal, wood and paraffin contributes to air pollution. This burning produces sulphur dioxide, carbon dioxide, carbon monoxide and particles. This results in poor air quality and an unhealthy environment especially as most of the burning takes place in poorly ventilated rooms.

Refuse burning: The burning of refuse is very dangerous as the refuse is a mixture of many different materials. For example, if we burn plastics or tyres, dangerous substances are given off that can harm our environment.

Other sources like chemical sprays; households products such as tobacco and cigarette smoke; fumes from paint, hair spray, varnish, aerosol sprays; and many cleaning products we use in our homes.

Smog is produced when air pollutants react in the presence of sunlight. In South Africa, smog can be seen as a brownish haze layer over cities. The smog reduces visibility, mostly in the mornings and late afternoons. If ground temperatures are lower than those of the upper atmospheric layers, the smog can stay near the ground without spreading for a number of days.

Smog

Department of Environmental AffairsChief Directorate: Air Quality

ManagementPrivate Bag x447

Pretoria0001

E-mail: callcentre@environment.gov.za Website: www.environment.gov.za

Call centre: 086 111 2468