Quantitative health risk assessment of respiratory exposure to 1,3-Butadiene in a petrochemical industry

Background and aims: In recent decades, air quality in different work environments has been a major concern. It is clear that the chemical materials used in industries have a profound effect on the quality of workplace air. In 1942, the number of identified chemicals was about 600,000, in 1947 it was about 4 million, and in 2011 it was about 18 million, while the number of new chemical compounds increased from 1,000 to 2,000 annually. Many people around the world are exposed to a variety of chemicals in the various working environments. Exposure to these substances can lead to numerous health and carcinogenic effects on individuals. Among these substances, volatile organic compounds are one of the main contributors to air pollution and due to high vapor pressure, high evaporation rate and rapid release into the environment, many people are exposed and consequently have irreversible effects on their health in various occupations. Petrochemical industry is one of the industries where workers are exposed to high levels of chemical pollutants in their respiratory air. One of the hazardous volatile organic compounds used in workplaces, including petrochemicals, is 1,3-butadiene (molecular formula: C4H6). 1,3-Butadiene is a colorless gas with smells like gasoline. Many international agencies and government organizations, including the International Agency for Research on Cancer (IARC), have identified this chemical as a human carcinogen by inhalation and placed it in Group 1 of carcinogens. Health effects of this compound include stimulation of the nervous system, eyes, nose, airways, asthma, fatigue, low blood pressure, and heart rate as well as atrophy in the ovaries. Today, many international organizations, including the World Health Organization (WHO) and the US Environmental Protection Agency (USEPA), consider the use of quantitative risk assessment methods as the legal basis for chemical compounds. Generally, the health risk assessment process involves several steps, first identifying the existing hazards, then measuring the individualchr('39')s exposure, finally determining the relevant factors and measuring and evaluating the individualchr('39')s exposure to a particular substance, using different risk assessment methods, graphs, and dose-response values, the probability of adverse effects in the population is calculated. Therefore, due to the deleterious effects of the 1,3- butadiene on the health of those working in the petrochemical industry, and the