Efficacy of Chlorine Dioxide as a Gas and in Solution in the Inactivation of Two Trichothecene Mycotoxins

Abstract

The efficacy of chlorine dioxide (ClO2) in detoxifying two potential bioterrorism agents, the trichothecene mycotoxins verrucarin A and roridin A, was evaluated. In the first experiment, verrucarin A (1, 5, or 10 microg) and roridin A (5 or 10 microg) were each inoculated onto square-inch sections of glass, paper, and cloth and exposed to 1000 ppm of ClO2 for either 24 or 72 h at room temperature. In the second experiment, verrucarin A and roridin A (1 or 2 ppm in water) were treated with 200, 500, or 1000 ppm ClO2 for up to 116 h at room temperature in light and dark conditions (N = 9 per treatment for test and control). A yeast assay using Kluyveromyces marxianuswas used to quantify the toxicity of verrucarin A and roridin A. Additionally, high-performance liquid chromatography was performed on selected samples. Results for the first experiment showed that ClO2 treatment had no detectable effect on either toxin. For the second experiment, both toxins were completely inactivated at all tested concentrations in as little as 2 h after treatment with 1000 ppm ClO2. For verrucarin A, an effect was seen at the 500 ppm level, but this effect was not as strong as that observed at the 1000 ppm level. Roridin A toxicity was decreased after treatment with 200 and 500 ppm ClO2, but this was not significant until the 24-h exposure time was reached. These data show that ClO2 (in solution) can be effective for detoxification of roridin A or verrucarin A at selected concentrations and exposure times.

Effect of Gaseous Chlorine Dioxide on Indoor Microbial Contaminants

“…Furthermore, the gaseous ClO 2 exposure did not decrease the activity of two trichothecene mycotoxins (roridin A and verrucarin A) or trichothecene mycotoxins from S. chartarum spores. 22,33 These results are consistent with the data from our field study because no change was observed in the semiquantitative microscopic evaluation of tape samples to assess surface contamination, but a clear decrease was seen in the culturable and total count of airborne spores. Furthermore, an increasing trend was observed for endotoxin and (133)-␤-D-glucan both in the laboratory and field study supporting the results of Wilson et al on the inefficiency of ClO 2 treatment in reducing the concentrations of fungal components.…”

“…Furthermore, an increasing trend was observed for endotoxin and (133)-␤-D-glucan both in the laboratory and field study supporting the results of Wilson et al on the inefficiency of ClO 2 treatment in reducing the concentrations of fungal components. 22,33 Rendering microorganism nonculturable will prevent microbial growth and further production of harmful agents, such as endotoxin, (133)-␤-D-glucan, mycotoxins, and allergens. However, the destruction of bacterial cells, fungal spores, and hyphae during the treatment will not remove these components.…”

Biological detoxification of the mycotoxin deoxynivalenol and its use in genetically engineered crops and feed additives

“…In spite of these efforts, contamination of grain with DON continues to pose a threat to grain production. The chemical detoxification of DON in solution and on/in contaminated grains by ozone (Young et al 2006), ammonia, chlorine, hydrogen peroxide, sodium bisulfite (Young et al 1986), sodium carbonate (Abramson et al 2005), and chlorine dioxide (Wilson et al 2005) has been demonstrated, but its application on a large scale has been hampered by costs, safety concerns, and the negative impact on grain quality. The most promising technique for chemical detoxification of DON is reaction with sodium metabisulfite (Young et al 1987).…”

Mycotoxigenic Fusarium species associated with grain crops in South Africa – A review

“…Chemical degradation of DON has been achieved by ammonia, calcium hydroxide, chlorine, hydrochloric acid, ozone, sodium bisulfite, and sodium hydroxide. [133][134][135][136] However, the large-scale application of these methods are hampered by costs, safety concerns and the negative impact on grain quality. 137 Biological detoxification, defined as the enzymatic degradation of mycotoxins or modification of their structure that leads to less toxic products, offers an alternative method to reduce the mycotoxin content in food and feed products.…”