IDENTIFICATION, CHARACTERIZATION AND QUANTIFICATION OF NATURAL OCCURRING ASBESTOS IN SERPENTINITES OF SOUTHWEST PUERTO RICO: PRELIMINARY RESULTS

Natural occurring asbestos (NOA) occur in ultramafic bodies and had been found in serpentinites to the extent of being regulated by some US states (e.g., California), and being in process of development in states. Regulation of NOA in Puerto Rico serpentinites does not exist at the present time. In order to establish the need for regulation, a general survey determining the occurrence of asbestos in PR, needs to be done and is the purpose of this study. Preliminary data is presented and suggests the occurrence of chrysotile asbestos as the only or principal asbestos mineral found on the serpentinites. The occurrence is on the range of 2 to 5 vol. % by point counting method. Samples analyzed include outcrops in Sabana Grande and Cabo Rojo. Future analyses include more sampling evaluation, NIOSH 9200 Polarizing Light Microscopy standard for asbestos identification, and SEM imaging of the fibers.