Health risk assessment of metal fumes in an Iranian Mineral Salt company

Introduction: Salt is a crucial mineral for human health, however, a salt factory may lead to hazardous pollutant exposure. Heavy metal fumes are considered toxic for human health. This study aimed to investigate concentration and assess health risks posed by toxic fumes in a salt factory. Materials and methods: Three units in the factory including salt laboratory, maintenance and metalworks were sampled for Arsenic (As), chromium (Cr), cadmium (Cd), cobalt (Co) and lead (Pb) according to the National Institute for Occupational Safety and Health, NIOSH7300 method, and analyzed using Inductively Coupled Plasma-Atomic Emission Spectrometers (ICP-AES). Results: All hazardous levels of fumes were below the permissible limit. The highest concentration of toxic fumes (Cr) was found in the maintenance unit. With 0.0758 mg/m3, the highest total concentrations of heavy metals (tHM) was found in the maintenance unit (tHM for Salt laboratory=0.0281 mg/m3 and metalworks=0.0103 mg/m3). In salt laboratory, the metal fumes concentrations were ordered as Pb>As>Cd>Cr>Co; in maintenance unit: Cr>Pb>As>Co>Cd; in metalworks: Cr>As>Pb>Co>Cd. The total hazard quotient (tHQ) and lifetime cancer risk in salt laboratory unit were 5.11 and 4.93E-01, respectively; in maintenance the tHQ=9.35E+01 and LCR =5.90E-01; in metalworks tHQ=6.57 and LCR=4.95E-02. Conclusion: The pollutant levels were below the acceptable limit. Yet, the non-carcinogenic and carcinogenic risks that they pose are not negligible. Therefore, enhancing the efficiency of the ventilation system and additional monitoring on wearing protective equipment as preventive strategies are proposed