Determination of Mineral Fiber Concentrations in Fish Tissues

Abstract

Submicroscopic inorganic particle concentrations in tissue have not been quantitatively determined in the past because of a lack of sample preparation techniques capable of achieving the sensitivity required. The determination of whether mineral fibres in water are accumulated in aquatic organisms requires transmission electron microscope examination of bulk tissue residues rather than thin sections. The sample preparation method used for this investigation involved removal of water and organic matter by freeze-drying and low temperature ashing. Lake trout with a lifetime exposure to Lake Superior water containing amphibole fibers contained similar amphibole fibers particularly in the kidney and with low concentrations in muscle tissue. Lake trout from two locations with widely different water fiber concentrations had corresponding differences in tissue fiber concentrations. Analysis of other fish raised under laboratory conditions suggests that ingestion is the primary route for fiber accumulation.Key words: electron microscopy, fiber accumulation, asbestos, lake trout, brook trout, channel catfish, Arctic char