Bacillus spores in the mail: "ironing" out the anthrax problem

Area of Science:

• Microbiology
• Public Health
• Biosecurity

Background:

• Investigated home decontamination methods for Bacillus anthracis spores in mail following a bioterrorism threat.
• Assessed the efficacy of household iron's dry heat for sterilizing contaminated mail envelopes.

Purpose of the Study:

• To determine if a household iron's dry heat can effectively eliminate bacterial spores from mail.
• To evaluate potential damage to envelopes and legibility of contents after heat treatment.

Main Methods:

• Used Bacillus subtilis var. niger spores as a heat-resistant surrogate for B. anthracis.
• Exposed envelopes with 2.1 x 10(6) spores to iron's dry heat for 5, 10, and 15 minutes.
• Cultured contents for bacterial growth and inspected envelopes for damage and text readability.

Main Results:

• Effective sterilization of B. subtilis spores achieved at 160.01°C - 204.5°C for 5 minutes.
• No bacterial growth observed after 7 days of incubation.
• Envelopes showed no significant damage, and text remained legible.

Conclusions:

• Dry heat from a household iron can destroy Bacillus spores in mailing envelopes.
• The process does not cause significant envelope alteration or compromise text legibility.