Assessing persistence and long-range transport potential of current-use pesticides

Despite the fact that current-use pesticides (CUP) have different chemical properties to first-generation organochlorine products, the long-term and long-range environmental behavior of these chemicals is still unclear. Data for 45 active ingredients of CUPs were collected, most of which originate from the results of simulation tests submitted for authorization. According to the Stockholm Convention on persistent organic pollutants (POPs), two of the 45 CUPs exceed both screening level criteria for persistence and long-range transport potential (LRTP). Thirteen CUPs meet the persistence criterion and just one for LRTP. This classification is compared to the reference chemicals approach using overall persistence (P(ov)) and characteristic travel distance (CTD) calculated with a multimedia model. Although none of the 45 CUP have a CTD above the LRTP boundary line, three of them exceed the overall persistence criterion derived from legacy POPs for classification. Nineteen CUPs are transported over longer distances in water than in air. For such polar substances a LRTP boundary has yet to be defined. We recommend the multimedia model modeling approach to calculate P(ov) and LRTP as a second tier in persistence and LRTP assessment.