What is described herein is an environment-friendly, highly aqueous solution of 1,2-benzisothiazolin-3-one (BIT) which is free from volatile organic compounds (VOCs), glycols, derivatives of glycols, glycerols and/or derivatives of glycerols. The composition comprises: (i) about 0.1% to about 30% by wt. of BIT (ii) about 5% to about 15% by wt. of neutralizing agent (iii) about 50% to about 85% by wt. of water and (iv) about 0.1% to about 5% by wt. of chelating agent. The aqueous solution of BIT may further comprise at least one water soluble form of a co-biocide. The composition is efficient in protecting aqueous media against microbial attack in various industrial applications.
