Assessing the health risks of chemicals in a company supplying chemicals to drilling rigs in Southern Iran using COSHH, SHEM-SAM, and SQRA methods.

Chemical industries are among the process industries and cause many risks. The present research aimed to analyze the health risks of a chemical warehouse of drilling rigs chemical Supply Company based on COSHH (Control of Substances Hazardous to Health), CHEM-SAM (Chemical Risk Management Self-Assessment Model), and SQRA (Subjective Quantified Risk Assessment) methods in 2021. The information was collected based on document review, MSDS of chemicals, processes, employees, and chemical exposure. Flammability, toxicity, allergy-causing, corrosivity, reactivity, LD50, and permissible thresholds of chemicals were also collected. The present research results showed that out of 59 main chemicals in the operational processes of the chemical warehouse of drilling rigs, 14 chemicals are flammable, 22 cause allergy responses, and three can cause death if inhaled. According to the results of the CHEM-SAM method, the employees and people outside the organization are at medium and low chemical risk based on the current management of the chemical warehouse, respectively. The results of the COSHH health assessment showed that chemicals had low, medium, high, and very high risk in 31, 13, 12, and 3 cases, respectively. The high-risk cases consisted of Ammonium Nitrate، Caustic Soda, and Poly.Aluminum.Chloride. Health risk assessment was also performed using the SQRA method, and results showed that chemicals have a very low, low, medium, high, and very high risk in 27, 12, 8, 9, and 3 cases, respectively. The results showed that the adverse health effects of chemical exposure in the drilling industry are alarming. Employees of different sectors of oil and gas industries are exposed to chemicals.

Assessment of potentially toxic elements (PTEs) in atmospheric dry deposition of Hamedan Metropolis, west of Iran: pollution status, spatiotemporal variation, health risk implications, and source identification.

The present study was designed to assess concentrations, contamination levels, spatiotemporal variations, health hazards and source apportionment of potentially toxic elements (As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn, and V) of atmospheric dry deposition (ADD) in Hamedan Metropolis. In so doing, a total of 144 atmospheric dry deposition samples were collected from 12 sites during four seasons in 2023. The concentrations of the analyzed PTEs in dry deposition samples were determined using ICP-OES after samples were digested with acid. The results illustrated that the average contents of As, Cd, Cr, Cu, Ni, Pb, and Zn with 4.52, 0.591, 4.01, 36.5, 42.5, 10.9, 84.6, 69.6, 178, and 3.91 mg/kg, respectively, were higher than those in the background samples reported for Iran, which could indicate the anthropogenic origin of these PTEs. The highest quantities of the tested PTEs in various seasons were observed in summer and/or fall samples and their highest amount in various functional regions pertained to the samples collected from the commercial or industrial regions, showing the effect of seasonal changes on emission sources and human inputs. Values of average contamination factor (CF), geo-accumulation index (I-geo), and enrichment factor (EF) ranged from 0.013 to 4.45, - 7.07 to 1.56, and 0.120 to 41.3, respectively, showing 'slight to high' pollution, 'unpolluted to moderately polluted', and 'no enrichment to very severe enrichment' levels, respectively. The pollution load index (PLI) with an average value of 0.680 reflected slight pollution levels in the entire study area. The average hazard index (HI) values of the tested PTEs for the residents were all within the safe limit (< 1). Additionally, the total carcinogenic risk (TCR) values showed that the carcinogenic risk of As, Cr and Ni for both target groups were at an acceptable level. Based on the positive matrix factorization (PMF) model, non-exhaust emissions and natural sources, fossil fuel combustion and industrial emissions, and traffic sources were identified as the primary contributors to ADD pollution, accounting for 26%, 38%, and 36%, of the total pollution respectively. In conclusion, further research is recommended to investigate the source-oriented ecological and health risks associated with atmospheric dry deposition pollution.