Abstract
Two greenhouse studies were conducted to evaluate the effectiveness of chlorine dioxide (ClO2) granules as a soil fumigation alternative for methyl bromide. The objective of the first study was to determine the efficacy of chlorine dioxide granules to inactivate Bacillus subtilis spore samples placed in two soils and positioned at two soil depths in soil tubes. The objective of the second study was to measure ClO2 gas concentrations released over multiple days in the two soils. The granules were evenly distributed in the soils with datalogger/sensors positioned at two different locations (headspace and soil matrix). The first study achieved a maximum spore log10 reduction of 4.12 and 5.82 for play sand and mixed soil, respectively, for inoculated samples placed 8 cm deep in the soil tubes with a chlorine dioxide rate of 240 g/tube. There was a 21-fold increase in percent organic matter for the mixed soil when compared to the play sand soil. The increase in organic matter in the mixed soil resulted in a 1.7 log10 reduction decrease due to the absorption of the gas onto the organic matter. In the second study, chlorine dioxide was collected at the bottom of the soil instead of volatilizing into the headspace of the soil tube because it is denser than air. The ClO2 at the bottom of the soil was 3.95x and 3.8x higher than the headspace gas concentration for the mixed and play sand soil, respectively, as averaged over all test runs and periods. Both studies show that the chlorine dioxide granules are a promising alternative to soil fumigation with methyl bromide. Further research is needed to refine the granule formulation release rates and develop more economical application rates.References
National Institute for Occupational Safety and Health. 1994. Methyl bromide. https://www.cdc.gov/niosh/idlh/74839.html
Cao A, Guo M, Yan D, Mao L, Wang Q, Li Y, Duan X, Wang P. Evaluation of sulfuryl fluoride as a soil fumigant in China. Pest Manag Sci 2014; 70(2): 219-227. https://doi.org/10.1002/ps.3535
Su L, Shan Z, Ou Y, Tao C, Ruan Y, Li R, Shan Q. Novel soil fumigation strategy suppressed plant-parasitic nematodes associated with soil nematode community alterations in the field. App Soil Ecol 2017; 122: 135-142. https://doi.org/10.1016/j.apsoil.2017.09.039
Underwood R. 2020 Litter Reviver Plus+ https://litterreviverplus.com/
EPA. Inactivation of Bacillus anthracis spores in soil matrices with chlorine dioxide gas 2012; EPA 600/R/12/517.
Ryan SP, Lee SD, Calfee NW, Wood J, McDonald S, Clayton M, Griffin-Gatchalian N, Toutai A, Smith L, Nysewander M. Effect of inoculation method on determination of decontamination efficacy against Bacillus spores 2014. https://doi.org/10.1007/s11274-014-1684-2
Rastogi VK, Wallace L, Smith LS, Ryan SP, Martin B. Quantitative method to determine sporicidal decontamination of building surfaces by gaseous fumigants and issues related to laboratory-scale studies. Appl Env Microbiol 2009; 75: 3688- 3694. https://doi.org/10.1128/AEM.02592-08
Young SB, Setlow P. Mechanisms of Bacillus subtilis spore resistance to and killing by aqueous ozone. J Appl Microbiol 2004; 96: 1133-1142. https://doi.org/10.1111/j.1365-2672.2004.02236.x
Kirk E. “Bacillus subtilis.” Missouri S&T Microbiology 2009. http://web.mst.edu/~djwesten/MoW/BIO221_2009/B_subtilis.html
Świetlik J, Dąbrowska A, Raczyk-Stanisławiak U, Nawrocki J. Reactivity of natural organic matter fractions with chlorine dioxide and ozone. Water Res 2004; 38: 547-558. https://doi.org/10.1016/j.watres.2003.10.034
Li Y-J, Zhu N, Jia H-Q, Wu J-H, Yi Y, Qi J-C. Decontamination of Bacillus subtilis var. niger spores on selected surfaces by chlorine dioxide gas. Journal of Zhejiang University Science B 2012; 13(4): 254-260. https://doi.org/10.1631/jzus.B1100289
Nam H, Seo H-S, Bang J, Kim H, Beuchat LR, Ryu J-H. Efficacy of gaseous chlorine dioxide in inactivating Bacillus cereus spores attached to and in a biofilm on stainless steel. International Journal of Food Microbiology 2014; 188: 122-127. https://doi.org/10.1016/j.ijfoodmicro.2014.07.009
Han Y, Applegate B, Linton R, Nelson P. Decontamination of Bacillus thuringiensis spores on selected surfaces by chlorine dioxide gas. Journal of Environmental Health 2003; 66(4).
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