nitrogen dioxide

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Related to nitrogen dioxide: Nitrogen monoxide

nitrogen dioxide (NO2)

a brownish irritating gas that can be released from silage and the reaction of nitric acid with metals. It may produce symptoms of pulmonary damage in workers who perform ensilage tasks. Some studies indicate that measurable changes in pulmonary function occur when healthy individuals are exposed to NO2 concentrations of two to three parts per million.

nitrogen dioxide

NO2, a toxic greenhouse gas, produced primarily by the combustion of fossil fuels. It is a powerful oxidant that can cause lung injury when inhaled at high concentrations.
CAS # 10102-44-0
See also: nitrogen

nitrogen dioxide

A toxic oxide of nitrogen that in concentrations of over about 100 parts per million will cause irritation of the nose and throat, watering of the eyes, cough, headache, and nausea and vomiting. UK occupational exposure safe limits are 5 ppm for 15 minutes and 3 ppm for an 8 hour day.


a chemical element, atomic number 7, atomic weight 14.007, symbol N. See Table 6. It is a gas constituting about four-fifths of common air; chemically it is almost inert. It is not poisonous but is fatal if breathed alone because of oxygen deprivation. Nitrogen occurs in proteins and amino acids and is thus present in all living cells.

nitrogen balance
the state of the body in regard to the rate of protein intake and protein utilization. When protein is metabolized, about 90% of the protein nitrogen is excreted in the urine in the form of urea, uric acid, creatinine and other nitrogen end products. The remaining 10% of the nitrogen is eliminated in the feces.
A negative nitrogen balance occurs when more protein is utilized by the body than is taken in. A positive nitrogen balance implies a net gain of protein in the body. Negative nitrogen balance can be caused by such factors as malnutrition, debilitating diseases, blood loss and glucocorticoids. A positive balance can be caused by exercise, growth hormone and testosterone.
blood urea nitrogen (BUN)
see urea nitrogen.
nitrogen dioxide
see nitric oxide.
nitrogen fixation
conversion of atmospheric nitrogen into organic nitrogenous compounds by bacteria which may be symbiotic, e.g. Rhizopus spp., which grow on the roots of legumes and put those plants in an advantageous position with respect to nonlegumes.
nitrogen-free extract (NFE)
consists of carbohydrates, sugars, starches, and a major portion of the hemicellulose in feeds. Calculated when crude protein, fat, water, ash, and the fiber are added and the sum is subtracted from 100.
nitrogen mustards
a group of toxic, blistering alkylating agents homologous to dichlorodiethyl sulfide (mustard gas), some of which have been used as antineoplastics. The group includes mustine hydrochloride, cyclophosphamide, thiotepa, chlorambucil and melphalan.
nonprotein nitrogen (NPN)
1. the nitrogenous constituents of the blood exclusive of the protein bodies, consisting of the nitrogen of urea, uric acid, creatine, creatinine, amino acids, polypeptides, and an undetermined part known as rest nitrogen.
Measurement of nonprotein nitrogen is used as a test of renal function, but has been largely replaced by measurement of specific substances, e.g. urea and creatinine.
2. also used in relation to feeds and refers to those nitrogen-containing constituents which are not proteins, e.g. nucleic acids, amino sugars, urea, etc.
nitrogen trichloride
nitrogen washout test
measures the rate at which the nitrogen concentration in the expired air is reduced when the horse is made to breathe pure oxygen. The rate is less in incompetent lungs, e.g. those affected by emphysema.
References in periodicals archive ?
Most nitrogen dioxide is emitted from cars and power stations.
Among girls, exposure to nitrogen dioxide during the first trimester was associated with lower FEV1 growth and exposure to nitrogen dioxide during the second trimester was associated with lower FEF growth.
Transport - 30% of nitrogen dioxide and 18% of particulates.
Around one third of the nitrogen dioxide monitoring sites in the city centre are within acceptable levels but we do need to address those which have produced high readings.
A record was also taken of daily nitrogen dioxide exposure.
But the brown haze, which comes mainly from nitrogen dioxide, still settles over the South Coast region, despite that standard having been reached.
And the recent warm spell has made the problem worse - with levels of nitrogen dioxide more than double the Government's safety guidelines at three sites in traffic-choked Glasgow and Edinburgh.
Tokyo, Osaka, Fukuoka and 10 other prefectures failed to meet the standards for either pollutant, while excess nitrogen dioxide was detected at sites in 14 prefectures, and 33 prefectures did not meet the standard for SPM.
To arrive at a dollar value, Nowak multiplied the tons removed by the figure that economists use to estimate what pollutants cost society in external impacts such as rising health care costs: $6,750/t (metric ton) for nitrogen dioxide and for ozone, $1,650/t for sulfur dioxide, $950/t for carbon monoxide, and $4,500/t for particulate matter smaller than 10 microns.
Poisonings in indoor ice arenas from the carbon monoxide (CO) and nitrogen dioxide (N|O.
They found that children who resided in homes closer to freeways and with higher levels of nitrogen dioxide (NO2) -- a product of pollutants emitted from vehicle engines -- were more likely to have developed asthma.
Nitrogen dioxide is the main pre-cursor for ground-level ozone causing major respiratory problems and leading to premature death.