Table 1. Antibacterial effects of ClO2 gas on S. aureus and E. coli.
| Bacteria | Group | Sodium chlorite (ml/m3) | ||
|---|---|---|---|---|
| 0.25 | 1.0 | 4.0 | ||
| (Log10 CFU/disc) | ||||
| S. aureus | Control | 7.1 ± 0.22 | 7.4 ± 0.33 | 7.2 ± 0.36 |
| ClO2 gas | 2.1 ± 1.49** | 0.0 ± 0.00 | 0.0 ± 0.00 | |
| E. coli | Control | 3.5 ± 0.91 | 4.8 ± 0.45 | 4.8 ± 0.61 |
| ClO2 gas | 0.28 ± 0.20** | 0.0 ± 0.00 | 0.0 ± 0.00 | |
Three independent experiments were performed under high-humidity conditions (75% to 85%) using a humidifier. Paper discs with each bacterium were placed at 6 locations in the test room as shown in Fig. 1. ClO2 gas was generated by mixing 3.35% sodium chlorite solution and 85% phosphoric acid at a 10:1 ratio. Experiments were carried out at 0.25, 1.0 and 4.0 ml/m3 of 3.35% sodium chlorite solution. After 24 h of ClO2 gas exposure, the viable cell counts were determined as log10 CFU per disc. Data represent mean ± SD (n=3). **P<0.01, significantly different from control paper discs treated without ClO2 gas (Student’s t-test).