Universidade Federal de São Carlos (UFSCar), Centro de Ciências Agrárias (CCA), Departamento de Ciências da Natureza, Matemática e Educação, Grupo Abelhas e os Serviços Ambientais, Programa de Pós-Graduação em Agricultura e Ambiente, Araras, SP, Brazil.
Universidade Estadual de Campinas (UNICAMP), Instituto de Biologia (IB), Grupo de Genética e Genômica da Conservação, Programa de Pós-Graduação em Genética e Biologia Molecular, Campinas, SP, Brazil.
Environ Pollut. 2023 Feb 1;318:120842. doi: 10.1016/j.envpol.2022.120842. Epub 2022 Dec 9.
Discussions about environmental risk reassessment of pesticides have grown in the last decades, especially in tropical and subtropical regions since the diversity of bee species in these places is quite different. Stingless bees are highly affected by pesticides, and toxicity information is necessary to include them in the regulatory process of countries that hosts a diversity of these species. Therefore, the present study aimed to evaluate the Median Lethal Concentration (LC), estimate the Median Lethal Dose (LD) and compared the sensitivity of three species of stingless bees exposed to the commercial formulation of the neonicotinoid thiamethoxam (TMX). The LD was estimated based on the LC determined in the present study (LC = 0.329 ng a.i./μL for Tetragonisca angustula; 0.624 ng a.i./μL for Scaptotrigona postica, and 0.215 ng a.i./μL for Melipona scutellaris). Considering these data, toxicity endpoints were used to fit species sensitive distribution curves (SSD) and determine the sensitivity ratio. The results showed that all the stingless bees tested are more sensitive to TMX than the Apis mellifera, the model organism used in ecotoxicological tests. Regarding the oral LC, the most susceptible and most tolerant species were M. scutellaris > T. angustula > S. postica > A. mellifera. Following the same evaluated pattern, for the LD (considering the weight of the bees - ng a.i./g bee), we have: M. scutellaris > S. postica > T. angustula > A. mellifera, and without the weight considered (ng a.i./bee): T. angustula > M. scutellaris > S. postica > A. mellifera. The different sensitivities among stingless bee species highlight the importance of inserting more than one surrogate species with a variety of sizes in research and protocol development. Additionally, the research suggests the need to investigate patterns regarding the influence of body mass on pesticide sensitivity among stingless bee species.
几十年来，人们一直在讨论农药的环境风险再评估，特别是在热带和亚热带地区，因为这些地方的蜜蜂物种多样性有很大的不同。无刺蜜蜂对农药非常敏感，因此需要了解其毒性信息，以便将其纳入拥有多种无刺蜜蜂物种的国家的监管过程中。因此，本研究旨在评估三种无刺蜜蜂对新烟碱类噻虫嗪（TMX）商业制剂的半致死浓度（LC），估计半致死剂量（LD），并比较它们的敏感性。LD 是根据本研究中确定的 LC 来估算的（TMX 对 Tetragonisca angustula 的 LC 为 0.329ng a.i./μL；对 Scaptotrigona postica 的 LC 为 0.624ng a.i./μL；对 Melipona scutellaris 的 LC 为 0.215ng a.i./μL）。考虑到这些数据，毒性终点被用来拟合物种敏感分布曲线（SSD），并确定敏感性比值。结果表明，所有测试的无刺蜜蜂对 TMX 的敏感性都高于用于生态毒理学测试的模式生物——意大利蜜蜂。关于口服 LC，最敏感和最耐受的物种是 M. scutellaris>T. angustula>S. postica>A. mellifera。按照相同的评价模式，对于 LD（考虑蜜蜂的体重-ng a.i./g 蜜蜂），我们有：M. scutellaris>S. postica>T. angustula>A. mellifera；不考虑体重（ng a.i./bee）：T. angustula>M. scutellaris>S. postica>A. mellifera。无刺蜜蜂物种之间的不同敏感性突出了在研究和方案制定中插入多种体型的替代物种的重要性。此外，该研究还表明，需要研究关于蜜蜂物种对农药敏感性的体重影响模式。
