Peer review of the pesticide risk assessment of the active substance pyriproxyfen

Abstract

The conclusions of EFSA following the peer review of the initial risk assessments carried out by the competent authorities of the rapporteur Member State the Netherlands and co-rapporteur Member State Spain for the pesticide active substance pyriproxyfen and the assessment of applications for maximum residue levels (MRLs) are reported. The context of the peer review was that required by Commission Implementing Regulation (EU) No 844/2012. The conclusions were reached on the basis of the evaluation of the representative uses of pyriproxyfen as an insecticide on citrus fruit, pome fruit (apple, pears), tomatoes, ornamentals (field use) and tomatoes, ornamentals (greenhouse application). MRLs were assessed in citrus fruits. The reliable end points, appropriate for use in regulatory risk assessment and the proposed MRLs, are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified.

Lethal and Sublethal Effects of Pyriproxyfen on Apis and Non-Apis Bees

“…Pyriproxyfen is considered to have a low acute toxicity against the adult honey bees because the 48-h LD 50 (lethal dose 50%) values via oral and contact contaminations are both greater than 100 µg a.i. (active ingredient)/bee [99][100][101]. Machado Baptista et al [102] showed that the direct spraying of pyriproxyfen (Cordial 100 ® , EC-0.075) on Africanized workers of A. mellifera led to a LT 50 (lethal time 50%) value of 466 h. Using a sprayer at 0.58 mL/s and an average spraying rate of 0.00583 mL/cm 2 for simulating a normal field spraying, Costa et al [103] sprayed a Tiger ® commercial formulation of pyriproxyfen at 0.1 g a.i./L on groups of 10 honey bees.…”

“…The oral and contact LD 50 values (µg/bee) are commonly used with the recommended field treatment doses (g/ha) for calculating the hazard quotients (HQs). Thus, for example, with the highest field application rate of 225 g a.i./ha selected by EFSA [ 101 ] for pyriproxyfen and a contact or oral LD 50 on A. mellifera >100 µg a.i./bee, a HQ <2.3 (i.e., 225/100) is obtained. Poquet et al [ 107 ] have tried to refine the HQ calculation when the pesticides, including pyriproxyfen, are sprayed.…”

“…The non- Apis bees are overlooked in official risk and hazard assessment reports on pyriproxyfen. Only the recent EFSA report [ 101 ] provides information on Bombus terrestris and solitary bees. Thus, the acute toxicity of pyriproxyfen against B. terrestris by oral and contact contamination is given >72.8 µg a.i./bee and >100 µg a.i./bee, respectively.…”

“…Using a field application rate of 225 g a.i./ha for pyriproxyfen, a HQ by contact less than 2.3 is proposed. As regards the solitary bees, the names of the species are not given and all the toxicity data are extrapolated from those obtained on the honey bees [ 101 ]. Inspection of the literature shows the same trends with only a little bit more toxicity results on bumble bees than other non- Apis bees.…”

Fate of Pyriproxyfen in Soils and Plants

“…The study of the behavior of pyriproxyfen for a given crop in the growing conditions of a specific area is compulsory to estimate whether the established pre-harvest time ensures that the residue levels are below the maximum residue level (MRL) that is the highest concentration of pesticide that is legally tolerated in or on food when it is applied under good agricultural practices. Thus, recently, Efsa [19] proposed 0.4 mg/kg as MRL for the tomato and 0.7 mg/kg for the citrus.…”