Potential Dermal Exposure to Flonicamid and Risk Assessment of Applicators During Treatment in Apple Orchards

Abstract

Exposure and risk assessments of flonicamid for applicators were performed in apple orchards in Korea. Fifteen experiments were done with two experienced applicators under typical field conditions using a speed sprayer. In this study, cotton gloves, socks, masks, and dermal patches were used to monitor potential dermal exposure to flonicamid, and personal air samplers with XAD-2 resin and glass fiber filter were used to monitor potential inhalation exposure. The analytical methods were validated for the limit of detection, limit of quantitation, reproducibility, linearity of the calibration curve, and recovery of flonicamid from various exposure matrices. The results were encouraging and acceptable for an exposure study. The applicability of XAD-2 resin was evaluated via a trapping efficiency and breakthrough test. During the mixing/loading, the average total dermal exposure was 22.6 μg of flonicamid, corresponding to 4.5×10(-5)% of the prepared amount. For the spraying, the potential dermal exposure was 9.32 mg, and the ratio to applied amount was 1.9 × 10(-2%). The primary exposed body parts were the thigh (2.90 mg), upper arm (1.75 mg), and lower leg (1.66 mg). By comparison, absorbable quantity of exposure was small, only 1.62 μg (3.2×10(-6)%). The margin of safety (MOS) were calculated for risk assessment, in all sets of trials, MOS > 1, indicating the exposure level of flonicamid was considered to be safe in apple orchards. Although this was a limited study, it provided a good estimate of flonicamid exposure for orchard applicators.

Pesticide Exposure in Fruit-Growers: Comparing Levels and Determinants Assessed under Usual Conditions of Work (CANEPA Study) with Those Predicted by Registration Process (Agricultural Operator Exposure Model)

“…It involved no change in the usual conditions of work as most of the workers did not usually wear a coverall especially during application, no interference with usual working clothes and no thermal discomfort or limitation of movement [24]. This method was approved by the Organization for Economic Co-operation and Development (OECD) [25] and has been widely used in fruit-growing exposure studies [12,22,[26][27][28][29][30]. Eleven 10 × 10 cm patches were placed on the head (1 patch on a cap) and on different parts of the body directly on the skin: the arms (2 patches), forearms (2 patches), chest (1 patch), back (1 patch), thighs (2 patches) and lower legs (2 patches) (Appendix A, Figure A1).…”

“…Großkopf explained that cleaning was not considered as a modeling factor since its impact on exposure had not been demonstrated in studies included in the AOEM [11]. However, owing to contact with the contaminated surfaces of the spraying equipment [39], this final step has proven to create significant exposure in operators [15], increasing urinary levels of metabolites [27,38]. Overall, it was even found to be the phase with the most exposure in the CANEPA study [20].…”

Biotransformation of insecticide flonicamid by Aminobacter sp. CGMCC 1.17253 via nitrile hydratase catalysed hydration pathway

“…Studies have shown that flonicamid is less toxic to bees, honeybees and natural predators of insect pests compared with neonicotinoid insecticides and was recommended for widespread pest control (Zhao et al . 2015; Kodandaram et al . 2017; Abbas et al .…”

Biodegradation of the Insecticide Flonicamid by Alcaligenes faecalis CGMCC 17553 via Hydrolysis and Hydration Pathways Mediated by Nitrilase

“…Compared with neonicotinoid insecticides, studies have shown that flonicamid is less toxic to bees, honeybees, and natural predators of insect pests; hence, it was recommended for widespread pest control. 2,7,14,15 However, despite having decreased toxicity and being responsible for lower levels of residue buildup in the environment compared with neonicotinoid insecticides, flonicamid toxicity against predators of insect pests has been reported. For example, flonicamid was found to be toxic to coccinellid and chrysoperla, predators of pomegranate aphids, 16 while a 17.39% mortality rate was observed in adult Coccophagus japonicus wasps following exposure to flonica-mid.…”

“…Globally, neonicotinoids are the most commonly used class of insecticides; however, they pose a significant risk to wild bees and honeybees. − Therefore, several countries have banned the use of neonicotinoid insecticides, necessitating the development of alternative pest control products. Compared with neonicotinoid insecticides, studies have shown that flonicamid is less toxic to bees, honeybees, and natural predators of insect pests; hence, it was recommended for widespread pest control. ,,, …”