LAUSR

Abstract Off-target deposition is one of the major routes of pesticide entry into the environment. Several studies have been carried out employing different tracers in an attempt to estimate pesticide deposition in the environment. This paper, in contrast, reviews different off-target sampling methods using the pesticide active ingredient. A critical analysis has been conducted on the sampling methods as applied to (a) pesticides of different volatilities, (b) samplers constructed using different materials, and (c) global distribution of the studies carried out on different pesticides using these samplers. In the last twenty years, pesticide deposition sampling has been carried out using various samplers such as chromatography paper, glass and plastic petri dishes, glass microscope slides, stainless steel rods and discs, amongst others. Of these, most studies have reported the use of chromatography paper because of the numerous advantages that it possesses, including protecting the pesticides from photodegradation and volatilisation. Air dispersion software models applied to pesticide deposition have tended to either over-predict or under-predict the amount of surface deposition resulting from pesticide spray drift. In conclusion, more work needs to be done to standardise pesticide deposition monitoring methods, including the choice of the most appropriate sampler for a particular situation, in order to obtain comparable and accurate data.