Exhaust gas that they produce smaller quantities of toxic pollutants (e.g. oxides of nitrogen) than petrol and diesel engines of the same power. They produce larger quantities of carbon dioxide but less carbon monoxide due to more efficient combustion. Researchers from the University of California, Los Angeles School of Public Health say preliminary results of their statistical study of children listed in the California Cancer Registry born between 1998 and 2007 found that traffic pollution may be associated with a 5% to 15% increase in the likelihood of some cancers. A World Health Organization study found that diesel fumes cause an increase
Risk factors for breast cancer amines have been found to cause mammary cancer in rats. Studies have shown that women who eat higher amounts of overcooked meat, meaning more exposure to heterocyclic amines, have also been diagnosed with more post-menopausal breast cancer. Heterocyclic amines also have the ability to copy estrogen and in laboratory studies have been found to encourage the growth of cancerous tumors on human tissue. Benzene is a petrochemical solvent. Benzene exposure mostly originates from air pollution resulting from industrial burning, exhaust and gas fumes, as well as cigarette smoke. Petroleum, its distillates such as gasoline, auto and truck exhausts also contain