An improved polystyrene polymeric XAD-2 resin column extraction of 5beta-cholestan-3beta-ol from polluted water.

Appropriate methods and criteria for judging the degree of sewage contamination of water and its suitability for drinking or recreational uses are essential to safeguard the public health. 5beta-cholestan-3beta-ol seems to satisfy many, if not all, of the criteria required of a good indicator of fecal pollution. It was shown that this fecal sterol was strongly adsorbed to the polystyrene polymeric XAD-2 adsorbents at low pH, resulting in a 100% retention. The adsorbed sterols could be easily removed from the columns with acetone adjusted to pH 8.5-9 with concentrated NH4OH. It has also been demonstrated that large volumes of both fresh and sea water samples can be extracted by the "closed" column method in a relatively short time. The sensitivity of the column exceeded that of the conventional liquid-liquid partitioning procedure. With some modifications, the column extraction process can be incorporated in a fully- or semi-automated analytical procedure.