Characteristics and Health Risk Assessment of Mercury Exposure via Indoor and Outdoor Household Dust in Three Iranian Cities

Abstract

This study aims to increase our current knowledge on the concentration of particulate-bound mercury (PBM) in urban environments of three Iranian cities, where high concentrations of dust particles can act as carriers for mercury transport and deposition. A total of 172 dust samples were collected from Ahvaz, Asaluyeh, and Zabol residential houses and in outdoor air and were analyzed for total mercury content. Ahvaz is a highly industrialized city with large metallurgical plants, refineries, and major oil-related activities, which were assumed to contribute to elevated contents of PBM in this city. Very high levels of Hg contamination in Ahvaz indoor dust samples were calculated (Contamination Factor: CF > 6). Sampling sites in Asaluyeh are influenced by Hg emissions from the South Pars Gas Field. However, the results revealed a relatively lower concentration of PBM in Asaluyeh, with a low-to-moderate level of Hg contamination. This is likely ascribed to the lower content of total mercury in hydrocarbon gases than crude oil, in addition to the absence of metal smelting plants in this city compared to Ahvaz. Zabol, as a city devoid of industrial activity, presented the lowest levels of PBM concentration and contamination. Indoor dust in Ahvaz showed considerable potential to cause a non-carcinogenic health risk for children, mainly through the inhalation of PBM, while the health risk for other cities was below safe limits. The trend of health risk was found in the order of indoor > outdoor and children > adults in all studied cities.

Heavy Metal Pollution and Risk Assessment of Surface Dust in the Arid NW China

“…Abliz et al [ 134 ] reported that the main sources of Hg pollution are coal combustion industries and coal gangue dumps. The level of Hg in the environment has increased primarily as a result of industrialization and its byproducts [ 67 , 135 ]. With the second-largest gas reserves in the world, Asaluyeh has the largest oil and gas reserves in Iran.…”

“…Another large oasis city in Iran (Ahvaz) has a high contamination of HMs in surface dust, with Hg, Pb, Mn, V, and Cr exhibiting higher health risks to residents of both residential and industrial areas [ 66 ]. The concentration of particulate-bound Hg in the USD of different oasis cities (Ahvaz, Asaluyeh, and Zabol) is associated with industrial development and oil- and gas-related activities [ 67 ]. In addition, children pose a considerable non-carcinogenic health risk to their bodies through the inhalation of indoor dust in Ahvaz.…”

Associations between Urinary Mercury/Cadmium Concentrations and Anthropometric Features in Korean Children

“…Recent research has also demonstrated a correlation between residential atmospheric heavy metal concentrations and urinary mercury concentrations in Korean adults, suggesting that urinary mercury levels could be an alternative indicator for atmospheric mercury exposure [ 25 ]. The dynamics of outdoor air can introduce airborne mercury to indoor environments, influencing indoor air quality and, subsequently, house dust heavy metal concentrations [ 26 , 27 ]. Young children are particularly vulnerable to mercury exposure from house dust due to their frequent hand-to-mouth and object-to-mouth behaviors, proximity to the ground, and tendency to spend more time on the floor [ 8 ].…”

Pollution Indices, Floral Coverage and Newly Enzymatic Biomarker for Soil Heavy Metal Contamination Due to Industrial Activities At 6th October City, Egypt

“…Other potential indoor sources include building materials (furniture, paint, and fluorescent lamps), appliances, and electronics, including LCD displays, monitors, batteries, clothes dryers, irons, washing machines, fluorescent bulbs, neon lights, and thermometers. (Dahmardeh et al, 2022).…”