Benzene is a volatile organic compound belonging to aromatic hydrocarbons and a natural constituent of crude oil and its derivatives. It is a colorless, flammable liquid that tends to volatilize easily at room temperature.
According to the IARC, International Agency for Research on Cancer, it is considered a Class I carcinogen, that is, a substance for which there is definite evidence of carcinogenic induction in humans. It is absorbed by dermal contact or ingestion, but more frequently by inhalation.
Because benzene, like toulene and xylene is added to green gasoline because of its antiknockout action, motor vehicles are among the main emitters of the compound into the ambient air via exhaust gases from motor vehicles, which are fueled by gasoline. We find it in large percentages particularly in those areas of major urban densification or that are important junctions for traffic circulation.
Other sources of benzene for indoor pollution are industrial paints or glues, and finally the combustion of cigarette smoke. Benzene can also contaminate water and the environment through industrial discharges and air pollution. We also find it in the ambient air as a result of natural events such as forest fires or gas spills from volcanoes. Sometimes small percentages of benzene have been found in foods such as eggs, fish, and fruit demonstrating the easy permeability of this air pollutant.
It is considered a definite carcinogenic substance according to Legislative Decree 81/2008 of the Consolidated Occupational Health and Safety Act. The etiopathogenetic mechanism in relation to the development of benzene-related leukemia finds reason in the toxicity generated on the bone marrow by metabolites of the product with mutation of cellular DNA and induction of oxidative stress. In particular, damage is generated by benzoquinone muconaldehyde that alters the cell differentiation stages with regard to progenitor cells of the hematopoietic system. In fact, benzene is rapidly metabolized in the liver and becomes water-soluble in about 48 hours, and is then released in the urine.
The most highly exposed category of workers are vehicle repair workers, gasoline workers, workers in shoe manufacturing, print shop operators, chemical and pharmaceutical laboratory operators, and operators in the pesticide, explosives, drug and cosmetics industries.
Workers with secondary occupational exposure are those who work in environments at higher risk of environmental contamination such as traffic policemen, bus drivers or cab drivers.
Benzene is a carcinogen capable of causing leukemia and listed on List I in INAIL, Group 6. For colors whose there is definite evidence of exposure to benzene, INAIL must compensate for the disease. The employer is instructed to create the best conditions useful to reduce the risk through preventive maneuvers such as:
- avoid smoking in enclosed spaces;
- avoid benzene-containing materials;
- ventilate rooms when possible sources of the compound are located in them;
- equip mechanical ventilation systems with filters properly monitored by a maintainer.
To assess the concentration of benzene in the air of the working environment, on the other hand, the current regulations refer to Legislative Decree No. 155 of August 13, 2010, which sets quality objectives and limit value of concentrations of various substances, including benzene.
In addition to the existing regulations to protect health, it is essential to put in place health surveillance for those who are most exposed through clinical and biological monitoring or process of removal of the professional once a threshold value of exposure is established.
Sources
- MINISTRY OF HEALTH
- AIRC
- D.lgs. 81/08
- ISS
