Spatial distribution of BTEX emission and health risk assessment in the ambient air of pars special economic energy zone (PSEEZ) using passive sampling.

Benzene, toluene, ethylbenzene and xylene (BTEX) are a challenging group of volatile organic compounds in industrial and energy areas. Since these aromatics may cause serious diseases such as cancer and respiratory illnesses, they must be monitored. Pars Special Economic Energy Zone (PSEEZ) in Iran is the second largest energy zone of the world with numerous gas refineries and petrochemical complexes for producing a wide range of products. This study is focused on determination of BTEX concentration in the whole South Pars area (46 sampling points) which is the active site of PSEEZ using passive sampling. Then, the results of the passive sampling are used for providing spatial distribution of BTEX using GIS. The annual BTEX measurements revealed that benzene and toluene concentration violates the maximum permitted values at numerous points most of which are located in the vicinity of petrochemical complexes. Active sampling in these complexes not only confirms the results of passive sampling, but also suggests a more intensified BTEX pollution in the air quality of the area which reaches as high as 3500 μg.m-3 and 18,000 μg.m-3 for benzene and toluene, respectively, being far beyond the acceptable standards. Health risk analysis also confirms the intensity of BTEX at the selected points. This study suggests a reconsideration of the location of non-operational sites and personnel who are more vulnerable to BTEX contamination. Also, BTEX profile provided by GIS in this research gives a suitable plan for relocating.