Cytotoxicity of asbestos, glass wool, MWCNT
and carbon black in BEAS 2B cells (trypan blue exclusion assay). The number of living cells is expressed as percentage of the number of living cells in control cultures. Symbols represent means (4 replicates ± SE). IC50 (as defined by fitting the data to a logarithmic trend line) is indicated by numbers in respective colour on the x- axis.