Departamento de Ecología y Gestión Ambiental, Centro Universitario Regional del Este (CURE), Universidad de la República, Tacuarembó entre Saravia y Bvar. Artigas, Maldonado CP 20000, Uruguay.
Departamento de Desarrollo Tecnológico, Centro Universitario Regional del Este (CURE), Universidad de la República, Ruta 9 y Ruta 15, CP 27000 Rocha, Uruguay; Grupo de Análisis de Compuestos Traza, Cátedra de Farmacognosia y Productos Naturales, Departamento de Química Orgánica, Facultad de Química, Universidad de la República, General Flores 2124, 11800 Montevideo, Uruguay.
Sci Total Environ. 2024 Feb 1;910:168704. doi: 10.1016/j.scitotenv.2023.168704. Epub 2023 Nov 20.
Environmental concentrations of 25 pesticides in superficial water were employed to conduct an ecological risk assessment (ERA) in a mixed land-use basin utilized as a drinking water source. A deterministic risk assessment (RQ) was utilized to evaluate the chronic risk to aquatic biota, while a probabilistic risk assessment (PRA) approach was applied to assess the acute and chronic risk in the most sensitive species and at the community level. A high risk was identified for insecticides (pyrethroids, organophosphates and organochlorines). RQs ranged from 4.0e (2,4-D) to 105.3 (ethion) considering median concentrations and from 8.0e (2,4-D) to 230 (p,p'-DDT) considering extreme concentrations. Temporal variation in ΣRQs showed the highest risk during spring and summer months, which is related to the crop calendar and land use in the Laguna del Cisne basin. For PRA, the probability of exceeding the hazardous concentration HC5 (5th percentile) was higher for the most sensitive species in chronic exposure, especially for cypermethrin (38.9 %), permethrin (25.6 %), and chlorpyrifos (16.6 %). In the case of acute exposures, the probability of surpassing HC5 was higher for the entire freshwater biota, with the highest values observed for bifenthrin (28.3 %), cypermethrin (25.5 %), permethrin (11.75 %), and ethion (11.1 %). The advantages and disadvantages of PRA for assessing pesticide ecological risk were compared with the conventional deterministic RQs approach, highlighting that PRA offers improvements over the deterministic risk assessment, especially for organophosphate pesticides. Additionally, PRA provides a more comprehensive evaluation of risk for both short and long-term exposure, has the potential to incorporate others available toxicity data (e.g., LD50, Daily Intake), and utilizes different hazardous concentrations, such as HC5, HC10, and HC50. Our findings emphasize the urgent need to establish a national regulatory framework to evaluate and mitigate pesticide risks in aquatic ecosystems, especially in drinking water source like Laguna del Cisne.
采用表层水中 25 种农药的环境浓度对作为饮用水源的混合土地利用流域进行了生态风险评估（ERA）。利用确定性风险评估（RQ）评估水生生物的慢性风险，而概率风险评估（PRA）方法则用于评估最敏感物种和群落水平的急性和慢性风险。发现杀虫剂（拟除虫菊酯类、有机磷类和有机氯类）存在高风险。考虑到中位数浓度，RQ 范围从 4.0e（2,4-D）到 105.3（乙硫磷），考虑到极端浓度，RQ 范围从 8.0e（2,4-D）到 230（p,p'-DDT）。ΣRQ 的时间变化表明，在春季和夏季月份风险最高，这与拉古纳德尔西斯内流域的作物日历和土地利用有关。对于 PRA，慢性暴露中最敏感物种超过危险浓度 HC5（第 5 个百分位数）的概率更高，尤其是氯氰菊酯（38.9％）、氯菊酯（25.6％）和毒死蜱（16.6％）。在急性暴露的情况下，整个淡水生物群超过 HC5 的概率更高，其中联苯菊酯（28.3％）、氯氰菊酯（25.5％）、氯菊酯（11.75％）和乙硫磷（11.1％）的值最高。与传统的确定性 RQ 方法相比，PRA 评估农药生态风险的优缺点进行了比较，结果表明 PRA 优于确定性风险评估，特别是对于有机磷农药。此外，PRA 为短期和长期暴露提供了更全面的风险评估，有可能纳入其他可用的毒性数据（例如 LD50、每日摄入量），并利用不同的危险浓度，如 HC5、HC10 和 HC50。我们的研究结果强调，迫切需要建立一个国家监管框架，以评估和减轻水生生态系统中的农药风险，特别是在拉古纳德尔西斯内这样的饮用水源。
