The Biocidal Products Directive (BPD) gives a formal definition of a biocidal product as: “Active substances and preparations containing one or more active substances, put up in the form in which they are supplied to the user, intended to destroy, deter, render harmless, prevent the action of, or otherwise exert a controlling effect on any harmful organism by chemical or biological means.” So despite the name ‘biocide’, a biocidal product does not actually have to kill. If it is used to destroy, deter, make harmless, or control a harmful organism by chemical or biological means it is considered to be a biocide. For example a repellent used to ‘deter’ a mosquito could be considered to be a biocidal product.

