Irradiation of shellfish was considered as a means to control bacterial contaminants (Licciardello et al. 1989 )-Vibrio parahaemolyticus should be a special concern, as its presence is not related to fecal contamination of the growing water. In this connection, the irradiation process was examined as to its probable effect on contaminating enteric viruses. This was a time when aquarium studies of virus uptake and depuration of shellfish were rare (Power and Collins 1989) , and so it was an accepted practice to inject virus into the soft tissue (no specific organ) of shellfish for irradiation. A first such study was conducted in the 60 Co irradiation facility of the University of Lowell, Massachusetts, with HAV and rotavirus in hard-shell clams (Mercenaria mercenaria) and eastern oysters (Crassostrea virginica) (Mallett et al. 1991) . Viruses produced at the Baylor College of Medicine were inoculated into the shellfish at the University of Lowell (no details given), irradiated, shucked, and shipped back to Baylor for assay. The virus extraction process was not described. Decimal reduction (D 10 ) values of 2.0 kGy were reported for HAV, and 2.4 kGy for rotavirus; irradiation of live, un-inoculated shellfish at these doses was said to have minimal adverse effects on their viability and their palatability after various styles of cooking.