Use of bituminous coal as an alternative technique for field concentration of waterborne viruses.

A filter system that sandwiches a bituminous coal preparation between two prefilters was comparable to those presently used to recover human viruses from large volumes of water. This filter was effective over a pH range of 3.0 to 7.0. Poliovirus type 1 recoveries from 100-liter seeded samples of Cincinnati tap water did not vary significantly when compared with those of identical samples processed through Filterite and Millipore filters. In studies with raw domestic sewage, virus recoveries were nearly identical from comparable samples filtered through coal and Millipore disk filters. Thus, the availability of coal makes this filter system an inexpensive analytical tool, especially in developing nations, for virus concentration.