In the growing of crops for consumption, a method for the removal of pathogens includes the addition to irrigation water for the crops of an anti-pathogen composition and supplying the anti-pathogen composition to the crops prior to harvest while normal irrigation is effected. The anti-pathogen composition is based on halogens, such as chlorine, bromine and iodine, or mixtures of halogens or halogens combined with other organic radicals including cyanurate, hydantoin, peroxide and chlorine dioxide. BCDMH and TICA are preferred anti-pathogen components of the anti-pathogen composition and may be added to a carrier concentrate and measured and dosed into the irrigation water.