CHAPTER 34. Use of Micronucleus Assays to Measure DNA Damage Caused by Coal Dust and Ash

Coal mining and combustion for energy generation can generate environmental pollutants during all processes, from extraction to combustion, causing significant impacts on the environment and the health of surrounding areas. Many studies have shown that the micronucleus test has become an important tool for assessing DNA damage related with this type of exposure, being the method of choice for occupational and/or environmental exposure evaluation. The main goal of this chapter is to review studies from literature to assess the evidence of a relationship between the exposure to mineral coal dust and ash and micronucleus frequency in different organisms. Human cells, fish, rodents, iguana, molluscs, plants, and culture cells exposed to coal and/or by-products as a complex mixture in situ or under laboratory conditions assessed by micronucleus test are evaluated in this chapter. Data from 49 studies were analysed in relation to the effect of complex mixture exposure on micronucleus frequency in different cells types (e.g. lymphocytes, buccal cells, and haemocytes). Other biomarkers were also evaluated, such as chromosomal aberrations, sister chromatid exchange, and comet assay. Most of these studies (>80%) showed a significant increase in micronucleated cells in the exposed groups in relation to the control groups, besides significant changes in other biomarkers.