A critical review of currently used single-dose rodenticides.

The introduction of the anticoagulants in the early 1950s, with their much greater safety to nontarget animals, resulted in a general decline in the use of single-dose rodenticides. However, the appearance of rodent resistance to the anticoagulants, first in the United Kingdom, later elsewhere in Europe, and still more recently in the USA, has revived interest in the use of single-dose rodenticides. Unfortunately, owing to their danger to nontarget mammals, the use of several of these compounds must be restricted; others, despite their long use, are now recognized to be unsatisfactory because of their poor acceptance or reacceptance by rats and mice. Thus, only very few compounds of this type are available for unrestricted use and there is an urgent need for the development of effective alternatives.