The present disclosure provides methods for generating percarboxylic acid compositions and/or peroxycarboxylic acid compositions formed external to a point of use in non-equilibrium reactions for use in certain bleaching and antimicrobial applications, in particular laundry applications. The compositions are generated external to a point of use, at alkaline pH levels, viz. greater than about pH 12, and optionally suitable for use with detergents and/or surfactants for synergistic bleaching efficacy. Methods of bleaching and/or disinfecting are further provided.