Infectivity studies of both ash and air emissions from simulated incineration of scrapie-contaminated tissues.

We investigated the effectiveness of 15 min exposures to 600 and 1000 degrees C in continuous flow normal and starved-air incineration-like conditions to inactivate samples of pooled brain macerates from hamsters infected with the 263K strain of hamster-adapted scrapie with an infectivity titer in excess of 10(9) mean lethal doses (LD50) per g. Bioassays of the ash, outflow tubing residues, and vented emissions from heating 1 g of tissue samples yielded a total of two transmissions among 21 inoculated animals from the ash of a single specimen burned in normal air at 600 degrees C. No other ash, residue, or emission from samples heated at either 600 or 1000 degrees C, under either normal or starved-air conditions, transmitted disease.

Reduction in radioactive material use and waste generation at the National Institutes of Health.

The National Institutes of Health (NIH) has implemented an enhanced and comprehensive program to reduce the use of radioactive materials and to minimize the generation of radioactive and mixed wastes. The primary drivers for this program were increasing waste management costs, difficulties in disposing of certain types of radioactive wastes, particularly mixed wastes, and the increasing burden of managing radioactive materials in accordance with new regulatory requirements. These minimization efforts, coupled with the development of new on-site waste treatment options and the use of commercially available waste processing facilities, have resulted in significant reductions in the use of radioactive materials in bench research and the resultant amounts of radioactive and mixed waste generated and disposed off-site.