Estimating rock and slag wool fiber dissolution rate from composition

A method was tested for calculating the dissolution rate constant in the lu ng for a wide variety of synthetic vitreous silicate fibers from the oxide composition in weight percent. It is based upon expressing the logarithm of the dissolution rate as a linear function of the composition and using a d ifferent set of coefficients for different types of fibers. The method was applied to 29 fiber compositions including rock and slag fibers as well as refractory ceramic and special-purpose, thin E-glass fibers and borosilicat e glass fibers for which in vivo measurements have been carried out. These fibers had dissolution rates that ranged over a racier of about 400, and th e calculated dissolution rates agreed with the in vivo values typically wit hin a factor of 4. The method presented here is similar to one developed pr eviously for borosilicate glass fibers that was accurate to a factor of 1.2 5. The present coefficients work over a much broader range of composition t han the borosilicate ones but with less accuracy. The dissolution rate cons tant of a fiber may be used to estimate whether disease would occur in anim al inhalation or intraperitoneal injection studies of that fiber.