Nitrogen dioxide in the air also reacts with water vapor to form nitric acid, one of the types of acid in acid rain. Nitrogen dioxide concentration in unpolluted air is around 10 parts per billion ppb. In smog, the concentration rises twenty-fold to about ppb.
Although nitrogen oxides have gained dubious distinction as pollutants, they are also used beneficially in some industrial processes. Nitric oxide is manufactured on a large scale, and is subsequently used to make nitric acid HNO 3. To create nitric oxide for industrial uses, chemists combine ammonia NH 3 with oxygen O 2 , releasing water H 2 O as a byproduct.
Nitrogen compounds derived from nitric acid are used to create chemical fertilizers, explosives, and other useful substances. Skip to main content. Sources of Nitrogen Oxides Scientists estimate that nature produces between 20 and 90 million tons of nitrogen oxides on Earth each year.
High levels of NOx can have a negative effect on vegetation by making it more susceptible to disease and frost damage. When NOx reacts with other pollutants in the presence of sunlight, it forms ozone. Ozone at high concentrations also damage vegetation. Air pollution occurs when gases, dust particles, fumes or odour are introduced into the atmosphere which has harmful or poisonous effects.
The common air pollutants are also known as criteria pollutants :. The amount of nitrogen oxides emitted into the atmosphere as air pollution, from both man-made sources, can be quite significant.
While NO 2 is a primary pollutant, it is also a contributing component for secondary pollutants formed from a chemical reaction.
The most common is ozone. Photochemical smog, most common in sunny, dry locations, is created when NO 2 from gas combustion is exposed to sunlight, splits and releases an oxygen ion O. The released O combines with oxygen molecule O 2 forming ozone O 3. Ozone is one of the major secondary pollutants. You can read more about ozone pollution in our blog: Why do I have an ozone pollution problem and what can I do about it? Indoor NO 2 levels are a result of both indoor and outdoor sources. While indoor NO 2 is produced by unvented heaters and gas stoves, high outdoor NO 2 levels originating from local traffic and other combustion sources can influence indoor levels.
Air pollution is a serious problem and we should all be concerned. Worldwide, more deaths per year are linked to air pollution than to automobile accidents. NO 2 is both a primary and secondary pollutant. Air pollution impacts everyone but some of us are more susceptible than others: children and seniors, people with existing lung and heart conditions, people working and exercising outdoors.
To combat the serious health effects it is important to find out more about air pollution, such as areas of heavy concentration, elements of composition and cause. To get this information, comprehensive air quality monitoring must be undertaken using air monitoring devices, such as shown below. These can be portable, ideal for checking pollution hot-spots or personal exposure, or fixed monitors, which measure the air continuously so you know when NO 2 levels are high. Both measure the air in real-time giving you accurate readings to make informed decisions.
Portable monitors to measure NO 2. Aeroqual makes sensors and equipment for air quality monitoring. Monitoring NO 2 and other pollutants is easy as See our portable outdoor air quality monitors to learn more. She enjoys guiding them to find the right solution to help them understand the air they breathe. NO 2 is used as the indicator for the larger group of nitrogen oxides.
NO 2 primarily gets in the air from the burning of fuel. NO 2 forms from emissions from cars, trucks and buses, power plants, and off-road equipment. Breathing air with a high concentration of NO 2 can irritate airways in the human respiratory system. Such exposures over short periods can aggravate respiratory diseases, particularly asthma, leading to respiratory symptoms such as coughing, wheezing or difficulty breathing , hospital admissions and visits to emergency rooms.
Longer exposures to elevated concentrations of NO 2 may contribute to the development of asthma and potentially increase susceptibility to respiratory infections. People with asthma, as well as children and the elderly are generally at greater risk for the health effects of NO 2. NO 2 along with other NO x reacts with other chemicals in the air to form both particulate matter and ozone.
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