IMPACTO DO GLIFOSATO EM ABELHAS NATIVAS TETRAGONISCA ANGUSTULA: ECOTOXICIDADE E CONSEQUÊNCIAS DE EXPOSIÇÃO TÓPICA E RESIDUAL PARA POLINIZADORES

Abstract

This study evaluated the impact of Glyphosate [pure (P.A.) and commercial] on the bee Tetragonisca angustula, which is an essential organism for pollination, aiming to understand its effects on bees through exposure to different herbicide concentrations, with a view to contributing to more sustainable agricultural practices, in the context of agrochemicals, and the biodiversity preservation. The results indicate that Glyphosate presents different toxicities among the formulations, requiring further research and measures to minimize its environmental impact. The lethal concentration for 10% of bees in 48 hours (DL10-48h) and the lethal concentration for 50% of bees in 48 hours (DL50-48h) varied between the tested formulations. Similarly, the No Observed Effect Concentration (NOEC) and the Observed Effect Concentration (LOEC) also showed variations. Toxicity tests for Pure Glyphosate (P.A.) revealed that the lethal concentration for 10% of bees in 48 hours (DL10-48h) was 2269.83 mg/L for Acute Residual Effect (ARE), while the lethal concentration for 50% of bees (DL50-48h) reached 58355.90 mg/L. For Acute Topical Effect (ATE), the DL10-48h was 15926.80 mg/L, and the DL50-48h was 11075.00 mg/L. For Glyphotal TR ® , the obtained values were 644.11 mg a.i./L for DL10-48h and 4136.94 mg a.i./L for DL50-48h in ARE. In ATE, the DL10-48h was 635.30 mg a.i./L, and the DL50-48h was 9801.76 mg a.i./L. For Pocco ® , the DL10-48h for ARE was 715.12 mg a.i./L, with the DL50-48h at 6424.70 mg a.i./L. For ATE, the values were 595.53 mg a.i./L for DL10-48h and 8898.98 mg a.i./L for DL50-48h . Results for Pilarsato ® showed an DL10-48h for ARE of 945.49 mg a.i./L and an DL50-48h of 9088.72 mg a.i./L. In ATE, the DL10-48h was 874.49 mg a.i./L, and the DL50-48h was 13332.30 mg a.i./L. For Templo ® , the values were 3329.97 mg a.i./L for DL10-48h and 15182.90 mg a.i./L for DL50-48h in ARE. In ATE, the DL10-48h was 3182.27 mg a.i./L, while the DL50-48h was 29955.00 mg a.i./L. The NOEC in the Food Preference Test for the different compounds were: 500.00 mg/L for Pure Glyphosate, 2000.00 mg a.i./L for Glyphotal TR ® , 2000.00 mg a.i./L for Pocco ® , 16000.00 mg a.i./L for Pilarsato ® , and 4000.00 mg a.i./L for Templo ® . The LOEC in the Food Preference Test were: 1000.00 mg/L for Pure Glyphosate, 4000.00 mg a.i./L for Glyphotal TR ® , 4000.00 mg a.i./L for Pocco ® , 32000.00 mg a.i./L for Pilarsato ® , and 8000.00 mg a.i./L for Templo ® . P.A. proved to be less lethal to bees, with Pilarsato ® showing more deleterious effects. In addition to evaluating the ecotoxicity of different glyphosate formulations, the study included a literature review (preceding the experimental study) about the impact of this herbicide on the health of native bees, with an emphasis on the species T. angustula. The review discusses how glyphosate, widely used in agricultural practices, contaminates pollen, nectar, and water, and the effects of this exposure on bees. Environmental concentrations and their potential impacts were discussed, highlighting behavioral and physiological changes in bees. In summary, this study significantly contributes to agrochemical science by comparing the toxicity of various glyphosate formulations, including pure glyphosate and commercial products, on the native bee T. angustula. This information is essential for developing more sustainable agricultural practices and protecting pollinators, as well as informing herbicide use regulations and paving the way for future research on long-term impacts.