The pollution levels in homes after a gas stove was used was significantly higher than previously thought of, suggests a recent study. Conducted by chemist Tara Kahan of the University of Saskatchewan and colleagues, the study found that the levels of nitrogen oxide pollutants sometimes exceed the health regulatory guidelines for a one-hour exposure, while the pollutants often lingered for a couple of hours. According to Kahan, this has a bigger effect than the indoor environment, where methane gas gets released which contributes to higher degrees of environmental pollution.