In polypropylene (PP), and p-xylene (PX) production. In comparison, a sample collected in the boundary site, upwind of the factory, represents the background of the industrial complex. In the basic chemical plant ( Fig. 1b), five samples were taken from ABS, SBL, PBL, SAN production, and ABS wastewater treatment areas (one in each area). Similarly, a sample was collected from chloromethane (1CM), dichloromethane and trichloromethane (2/3CM), PCE, and chloromethane storage tanks in the chlorinated chemical plant. Twenty-five samples in total were collected from various sites inside the three plants.