PREVENTING DISEASE THROUGH HEALTHY ENVIRONMENTS
EXPOSURE TO BENZENE : A MAJOR PUBLIC HEALTH CONCERN
Human exposure to benzene has been associated with a range of acute and long-term adverse health effects and diseases , including cancer and aplastic anaemia . Exposure can occur occupationally and domestically as a result of the ubiquitous use of benzene-containing petroleum products , including motor fuels and solvents . Active and passive exposure to tobacco smoke is also a significant source of exposure . Benzene is highly volatile , and exposure occurs mostly through inhalation . 1 – 3 Public health actions are needed to reduce the exposure of both workers and the general population to benzene .
Sources of exposure to benzene
Benzene is highly volatile , and most exposure is through inhalation . Benzene is degraded rapidly in the upper atmosphere . Because of its solubility in water , a minor amount may be removed by rain to contaminate surface waters and soil . However , it is not persistent in surface water or soil , either volatilizing back to air or being degraded by bacteria .
Industrial processes
As benzene occurs naturally in crude petroleum at levels up to 4 g / l , human activities using petroleum lead to exposure . These activities include processing of petroleum products , coking of coal , production of toluene , xylene and other aromatic compounds , and use in industrial and consumer products , as a chemical intermediate and as a component of petrol ( gasoline ) and heating oils . The presence of benzene in petrol and as a widely used industrial solvent can result in significant occupational exposure and widespread emissions to the environment . Automobile exhaust accounts for the largest source of benzene in the general environment . Off-gassing from building materials and structural fires lead to increased atmospheric benzene levels . Industrial discharge , landfill leachate and disposal of benzenecontaining waste are also sources of exposure . 2
Indoor residential air
Benzene has been detected at high levels in indoor air . Although some of this exposure might be from building materials ( paints , adhesives , etc .), most is from cigarette smoke in both homes and public spaces . Levels of benzene are higher in homes with attached garages than in those with detached garages . Levels are increased in homes close to petrol filling stations . 2 Benzene may be released to indoor air from unflued oil heating and from the use of benzenecontaining consumer products in residences . People spending more time indoors , such as children , are likely to have higher exposure to benzene .