Inactivation of spores by electric arcs

In the context of spore contamination involved in bio-terrorism and food preservation, the development of new techniques for spore inactivation is an important challenge.

Here, a successful application of electric arc discharges resulting in spore death was reported. Two types of electric arcs were compared, different with respect to their durations. The discharges with 0.5 μs duration induced a small inactivation area of 0.6 % of surface treated around their point of entry into the sample, while those with 20 μs duration induced a much larger inactivation area from 7 to 55 % of surface treated roughly proportional to the number of discharges delivered. In particular, 50 discharges of 20 μs duration induced inactivation in more than 55% of surface treated at an inactivation rate above 3.6 log10.

These results are promising and warrant developing electric arcing as a novel method for spore inactivation.