Michael Harding with Alberta Agriculture & Forestry recently compared 10 disinfectant solutions to see which is best to kill clubroot spores on machinery, tires and boots, etc. Four of those 10 products achieved 95% inactivation of clubroot resting spore viability, qualifying them as effective. Of the four, bleach achieved the 95% threshold at very low concentration (2%) and bleach is the lowest cost and easiest to find.