Fossil fuel percent of [its] weighted emissions in 1998. Combustion of fossil fuels also produces other air pollutants, such as nitrogen oxides, sulfur dioxide, volatile organic compounds and heavy metals. According to Environment Canada: "The electricity sector is unique among industrial sectors in its very large contribution to emissions associated with nearly all air issues. Electricity generation produces a large share of Canadian nitrogen oxides and sulphur dioxide emissions, which contribute to smog and acid rain and the formation of fine particulate matter. It is the largest uncontrolled industrial source of mercury emissions in Canada. Fossil fuel-fired electric power plants also emit
Nitrogen dioxide poisoning glutathione reductase, an enzyme that catalyzes the reduction of glutathione disulfide (GSSG) to the sulfhydryl form glutathione (GSH), which is a critical molecule in resisting "oxidative stress" and maintaining the reducing environment of the cell. Exposure to nitrogen dioxide has a significant effect on the male reproductive system by inhibiting the production of Sertoli cell, a "nurse" cell of the testicles that is part of a seminiferous tubule and helps in the process of spermatogenesis. These effects consequently retard the production of sperm cell. The effects of nitrogen dioxide poisoning of female reproduction may be linked with the effects of