Diesel engines emit a complex mixture of air pollutants, including both particles and gases. Diesel particulate matter includes soot, metallic abrasion particles, sulfates, and silicates. Because of their small size, inhaled particles may penetrate deep into the lungs. Exposures have been linked to symptoms such as headache, dizziness, nausea, coughing, difficulty in breathing, and irritation of the eyes , nose and throat. Prolonged exposures can lead to heart disease, lung disease, and lung cancer. It has been estimated that hundreds of New Jersey residents die or suffer respiratory illnesses every year from harmful diesel particulate matter.