Nitrogen oxides (NOx)Carbon monoxide (CO)Volatile organic compounds (VOCs)Sulfur oxides (SOx)Particulate matter (PM)Mercury.and more.

What are the 5 primary air pollutants?

• Ozone (O3)
• Nitrogen Oxides (NOx)
• Carbon Monoxide (CO)
• Sulfur Dioxide (SO2)
• Particulate Matter (PM10 and PM2.5)

How many primary pollutants are there?

The major primary pollutants are Oxides of Sulphur, Oxides of Nitrogen, Oxides of Carbon, Particulate Matter, Methane, Ammonia, Chlorofluorocarbons, Toxic metals etc. The secondary pollutants are not emitted directly.

What are the examples of primary pollutants?

Primary air pollutants: Pollutants that are formed and emitted directly from particular sources. Examples are particulates, carbon monoxide, nitrogen oxide, and sulfur oxide. Secondary air pollutants: Pollutants that are formed in the lower atmosphere by chemical reactions.

What is the most common primary pollutant?

What is the most abundant primary pollutant? oxides (NOx), volatile organic compounds (VOC), and particulate matter (PM) are the most prevalent primary pollutants.

What are the types of pollutants?

• Nitrogen oxides (NOx)
• Sulfur oxides (SOx)
• Particulate matter (PM)
• Ground level ozone (O3)
• Volatile organic compounds (VOCs)
• Mercury (Hg)
• Peroxyacyl nitrates (PANs)
• and more.

What are primary and secondary pollutants?

A primary pollutant is an air pollutant emitted directly from a source. A secondary pollutant is not directly emitted as such, but forms when other pollutants (primary pollutants) react in the atmosphere.

Is aerosol a secondary pollutant?

Secondary pollutants may be either gaseous, or particulate aerosols. … Aerosol pollutants may be formed within the atmosphere as a result of gas-phase reactions followed by condensation of the products, or by reactions taking place in the existing atmospheric aerosol phase.

Are VOCs primary pollutants?

Primary pollutants enter the air directly. They include carbon oxides, nitrogen oxides, sulfur oxides, particulates, volatile organic compounds (VOCs), and heavy metals. Secondary pollutants form from primary pollutants.

Is so2 a secondary pollutant?

Sulfur dioxide is also a natural byproduct of volcanic activity. Like nitrogen dioxide, sulfur dioxide can create secondary pollutants once released into the air. Secondary pollutants formed with sulfur dioxide include sulfate aerosols, particulate matter, and acid rain.

Article first time published on

What are the top pollutants?

• Carbon Monoxide.
• Nitrogen Dioxide (EPA)
• Ozone (EPA)
• Particulate Matter.
• Lead (EPA)
• Sulfur Dioxide.
• Six Common Pollutants (EPA)

Which of the following pollutants are primary pollutants?

Types of primary pollutants include: Nitrogen oxides (NOx) Carbon monoxide (CO) Volatile organic compounds (VOCs)

Is Pan a secondary pollutant?

Peroxyacetyl nitrate (PAN) and ozone are the two important secondary photochemical air pollutants found in the urban at- mosphere (1-3). Of the two, PAN is the more useful indicator of photochemical reactions in polluted air as, unlike ozone, it appears to have no large natural source (2-7).

Why ozone is called secondary pollutants?

Ground-level ozone is a colorless and highly irritating gas that forms just above the earth’s surface. It is called a “secondary” pollutant because it is produced when two primary pollutants react in sunlight and stagnant air. These two primary pollutants are nitrogen oxides (NOx) and volatile organic compounds (VOCs).

Is CO2 a secondary pollutant?

Carbon Monoxide (CO) Carbon monoxide is released from volcanoes and forest fires as well. Secondary pollutants like ozone and carbon dioxide (CO2), a greenhouse gas, come from carbon monoxide.

Which of the following is secondary pollutants?

Primary PollutantsSecondary PollutantsCarbon monoxide (CO) Oxides of nitrogen (NOx, NO) Sulfur oxides (SOx) Volatile organic compounds (VOCs) highly Particulate matter (dust, ash, salt particles)Ozone PAN Smog Formaldehyde Sulphuric Acid

What are the 4 types of pollutants?

The major kinds of pollution, usually classified by environment, are air pollution, water pollution, and land pollution. Modern society is also concerned about specific types of pollutants, such as noise pollution, thermal pollution, light pollution, and plastic pollution.

What are the 3 types of pollutants?

The three major types of pollution are air pollution, water pollution, and land pollution.

What are three types of pollutants?

Air, water, and soil pollution are the three major types of pollution. We also have noise, visual, light, thermal, and plastic pollution. Littering and radioactive contamination also causes pollution.

Is Mercury a primary pollutant?

Primary pollutants come directly from sources such as industrial facilities, automobiles and forest fires. These include sulfur and nitrogen compounds, particulate matter, volatile organic compounds such as paint fumes and solvents, and toxic metals such as mercury.

Which one is not an example of primary pollutants?

Ozone is not a primary pollutant since it is formed by the photo-chemical reaction of oxygen with the UV rays and not directly discharged into the atmosphere by a source. Similarly, sulphuric acid is also not a primary pollutant.

Which is the major photochemical smog?

Ground-level ozone constitutes one of the major components of photochemical smog, so called because of the photochemical reaction of air pollutants such as nitrogen oxides (NOx) and volatile organic compounds (VOCs) with ultraviolet light (sunlight); thus, the O3 levels vary strongly with season and the highest levels …

Are hydrocarbons primary or secondary pollutants?

The best known of the secondary pollutants are certain gases that are synthesized by photochemical reactions in the lower atmosphere. The primary emitted chemicals in these reactions are hydrocarbons and gaseous oxides of nitrogen such as nitric oxide and nitrogen dioxide.

Is ozone a secondary pollutant?

Ozone, unlike the other criteria pollutants, is not emitted directly into the air by any one source. Ground-level ozone is a secondary pollutant. It is formed through chemical reactions of other molecules already in the air, specifically nitrogen oxides (NOx) and volatile organic compounds (VOCs).

Why is no2 a secondary pollutant?

Nitrogen dioxide is also a secondary pollutant because it can be formed through oxidisation. Nitrogen dioxide further oxidises into nitric acid (HNO3), which can enter the environment through the ground as droplets or nitrate-containing particles.

Is photochemical smog a secondary pollutant?

Secondary pollutants are pollutants which form in the atmosphere. These pollutants are not emitted directly from a source (like vehicles or power plants). … Photochemical smog is made up of various secondary pollutants like ozone, peroxyacyl nitrates (PANs), and nitric acid (seen in Figure 2).

What is the full form of no2?

Nitrogen Dioxide (NO2) is one of a group of highly reactive gases known as oxides of nitrogen or nitrogen oxides (NOx).

What are some environmental pollutants?

• Chlorofluorocarbons (CFC) These are gases that are very destructive to the protective ozone layer. …
• Methane. …
• Carbon monoxide. …
• Particulate matter (PM) …
• Nitrogen oxides. …
• Sulfur dioxide. …
• Plastic. …
• Mercury.

What color is photochemical smog?

Photochemical smog is a brownish-gray haze caused by the action of solar ultraviolet radiation on atmosphere polluted with hydrocarbons and oxides of nitrogen.

Are Peroxyacyl nitrates a primary pollutant?

PANs are a secondary pollutant since they form in the atmosphere after the emission of primary pollutants. Sources of the pollutants required to create PANs include motor vehicles, tobacco smoke, and the burning of fossil fuels.

Is Peroxyacetyl nitrate a secondary pollutant?

Peroxyacetyl nitrate is a peroxyacyl nitrate. It is a secondary pollutant present in photochemical smog. It is thermally unstable and decomposes into peroxyethanoyl radicals and nitrogen dioxide gas. … Peroxyacetyl nitrate, or PAN, is an oxidant that is more stable than ozone.