It is not unusual for symptoms to occur up to two to three days after exposure. This is especially troubling because it means that individuals may find themselves taking in nitrogen dioxide without being aware of it. Because many high-action sports, such as hockey, take place in arenas, individuals will exert themselves and their metabolism will increase. This will cause, even deeper penetration of pollutants into the sensitive airways. There is also the potential that exposure will lead to a predisposition to respiratory infections, and chronic obstructive pulmonary disease.
Studies also indicate that children are more at risk than adults because of their smaller sizes.
This means they will inhale more fumes per body weight. Not surprisingly, every winter there are several incidents in North America where children end up in emergency wards of hospitals because of severe breathing problems. One of the worst incidents of this kind occurred in Seattle, Washington. Seventy-eight people of various ages were admitted to emergency wards suffering from fatigue, dizziness and headaches after attending an indoor skating arena facility that had elevated levels of carbon monoxide. In 1994 nitrogen dioxide poisoning in Sun Valley, Idaho, was suspected when one person almost died and three others had permanent lung damage.