You can be exposed to these oxides by breathing polluted air, which is most commonly found in areas with heavy motor vehicle traffic [7] Exposure to high levels of Nitrogen oxides damages tissues of the throat and upper respiratory tract and can interfere with the body's ability to carry oxygen. High exposure to nitrogen dioxide may cause fetal mutations, damage a developing fetus, and decrease a woman's ability to become pregnant. Studies have also shown that higher exposures to NO inhibit embryo development during both traditional pregnancies and artificial inseminations [8][9]