A small increase in NO2 is linked to increased heart and respiratory deaths.
A team of international researchers analyzed daily concentrations of NO2 in 398 cities in 22 low to high-income countries over a 45-year period.
There were a total of 62.8 million deaths over the 45-year study period, 31.5% of which were cardiovascular-related and 8.7% of which were respiratory-related.
The researchers found that on average, a 10 µg/m3 increase in NO2 concentration on the previous day was associated with 0.46% and 0.37% increase in the total, cardiovascular, and respiratory deaths, respectively.
What is NO2 and how does it get in the air?
Nitrogen dioxide (NO2) is one of a group of highly reactive gases known as oxides of nitrogen or nitrogen oxides (NOx). Other nitrogen oxides include nitrous acid and nitric acid. NO2 is used as the indicator for the larger group of nitrogen oxides.
NO2 primarily gets in the air from the burning of fuel. NO2 forms from emissions from cars, trucks and buses, power plants, and off-road equipment.
Effects of NO2
Breathing air with a high concentration of NO2 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 NO2 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 NO2.
NO2, along with other NOx, reacts with other chemicals in the air to form both particulate matter and ozone. Both of these are also harmful when inhaled due to effects on the respiratory system
- NO2 and other NOx interact with water, oxygen and other chemicals in the atmosphere to form acid rain. Acid rain harms sensitive ecosystems such as lakes and forests.
- The nitrate particles that result from NOx make the air hazy and difficult to see though. This affects the many national parks that we visit for the view.
- NOx in the atmosphere contributes to nutrient pollution in coastal waters.
Where do we find sulfur and nitrogen?
Regulating bodies all over the world have set challenging low levels of allowed sulfur and nitrogen concentrations in organic fuels for the present and near future in order to protect the environment.
Oil refineries produce a wide range of air and water emissions that can be harmful to the environment. Some of the contaminants are present in the original crude oil, while others are a result of refinery processes and operations. Air emissions include sulfur dioxide (SO2) and nitrogen dioxide (NO2), which have to be monitored.
During the production process of oil products, nitrogen oxides (NOx) are formed in the gases of the furnaces, which are corrosive to steel. In addition, during catalyst reforming, naphtha is pretreated to remove contaminants like chlorine, sulfur and nitrogen which could poison the catalyst. Right before the end-product is sent to blending and storage, the oil product is treated once more to remove the last amounts of nitrogen and sulfur completely.
Refineries need to monitor and control the total nitrogen and total sulfur content in the feedstock. This is the only way to tune their processes at the highest level of efficiency and also important in order to protect the quality of fuels which leads to a cleaner environment.
How do we measure NOx and SOx in these processes?
This advanced elemental combustion analyzer offers fast, accurate and precise analysis of liquid, LPG, gas and solid samples. It is designed to offer standardized and customized solutions to match current as well as future analytical needs, ranging from low ppb to high ppm applications.
Valuable information about a sample that contains both elements is created during a single run. With its low detection limit it is possible to measure concentrations at ppb level. Detection through Chemiluminescence and UV-Fluorescence with sample combustion at high temperature are the reference methods for the determination of Total Nitrogen and Total Sulfur.
Calibrating Total Nitrogen and Total Sulfur Analyzers
ASI has a full range of NIST traceable Calibration Standards made in accordance with our ISO 17034 accreditation guidelines that cover both the desired elemental ranges and matrices to satisfy these ASTM Methods. See our range of Sulfur and Nitrogen Standards.
- D5453 - Standard Test Method for Determination of Total Sulfur in Light Hydrocarbons, Motor Fuels and Oils by Ultraviolet Fluorescence
- D4629 - 17 Standard Test Method for Trace Nitrogen in Liquid Hydrocarbons by Syringe/Inlet Oxidative Combustion and Chemiluminescence Detection
- D6069 - 01 Test Method withdrawn and replaced with D7184
- D7184 - 20 Standard Test Method for Ultra Low Nitrogen in Aromatic Hydrocarbons by Oxidative Combustion and Reduced Pressure Chemiluminescence Detection
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