Modulation of biological processes by mineral fiber adsorption of macromolecules in vitro.

Three classes of macromolecules (i.e., DNA, RNA, and protein) were shown to be adsorbed to asbestiform minerals. The cytotoxicity exerted by the fibers on a normal human fibroblast cell line, which may be an indicator of the carcinogenic potential of mineral fibers, correlated positively with the degree of macromolecular adsorption of the fiber, namely: chrysotile greater than amosite greater than glass fiber. Asbestiform fibers also induce an alteration in in vitro DNA hydrolysis by bovine pancreatic deoxyribonuclease. This phenomenon suggests that adsorption by asbestiform minerals may modulate biological processes by inducing a conformational change in biological macromolecules as a result of coulombic interaction between the surface charge of the fiber and the hydrophilic groups on the macromolecule.