Review: Bioaccessibility of Potentially Harmful Metals in Dust and Soil Matrices

Dust is the most pervasive material affecting human health. Metal exposure to humans from dust is best assessed by bioaccessibility tests, which can be done by mimicking the conditions in the human digestive system. This review covers the works on metal bioaccessibility in dust and soil. Here, articles discussing research in this field and their bibliometric outputs have been reviewed. The Web of Science Core Collection Database was explored to collect the data, and bibliometric network analysis was performed using VOSviewer software. Research articles have broadly covered bioaccessibility and risks in urban/coking/smelting/mining plants, waste recycling, transport in vegetables, size distribution, chemical forms, daily intake, speciation, and the influence of matrix composition particle size, and source characterization. The different methods adopted for metal extraction studies have been discussed. Few of the significant findings were: the highest number of publications were observed in the year 2014; soil is the most studied matrix; China has maximum publications; metal immobilization is a vital technique to control metal leaching in the environment and manage metal exposures to humans. The most critical knowledge gaps identified are the standardization of metal extraction procedures and the formulation of realistic models for estimating metal exposure and their bioaccessibility. None of the studies have reported metal bioaccessibility from the perspective of non-invasive human bio monitors like hair or nail. More solution-oriented research would be required to curb the consequences of higher metal bioaccessibility, especially in the vulnerable classes (children/aged/ailing individuals). Further, the paper discusses different control measures, like dust wetting or metal immobilization.