Department of Environmental Sciences, University of Milano Bicocca, Piazza della Scienza 1, 20126, Milan, Italy.
Ecotoxicology. 2012 Nov;21(8):2177-85. doi: 10.1007/s10646-012-0971-7. Epub 2012 Jul 3.
As a general rule, environmental risk for chemicals is characterised by comparing an expected exposure level (e.g. PEC) with an ecotoxicological endpoint. The same approach is generally used for plant protection products (PPPs). However, in some cases, suitable procedures for a precise quantification of exposure are not available. The common risk assessment procedure for pollinators based on the hazard quotient, where the agronomic application rate is assumed as an exposure indicator, is an example. In this work, a semi-quantitative index to assess exposure to PPPs for organisms with a large forage area is presented. The proposed index was already applied in a previous work on risk assessment for pollinators, for this reason the validation steps (sampling area, collected samples, samples distribution) were planned bearing in mind the characteristic and the behaviour of these organisms and using Apis mellifera as representative of pollinators. The starting point for the development of the index is the assumption that exposure depends not only on environmental fate of pesticides but also on the feeding behaviour of the target organisms (in this context meant as target of the assessment). The developed index was applied and validated in different experimental areas of 4 × 4 km located in North-East Italy (Veneto region) characterised by a different level of impact. A sensitivity analysis of the index was performed evaluating the influence of the dataset resolution on the predictive efficiency. The obtained results indicate a good agreement between predicted and measured concentrations, supporting the suitability of the index to improve exposure assessment for pollinators.
一般来说，化学物质的环境风险是通过将预期暴露水平（如 PEC）与生态毒理学终点进行比较来确定的。同样的方法通常也适用于植物保护产品（PPPs）。然而，在某些情况下，无法获得精确量化暴露的适用程序。基于危害商数的授粉媒介共同风险评估程序就是一个例子，其中农业应用率被视为暴露指标。在这项工作中，提出了一种用于评估具有大面积饲料区的生物体接触 PPPs 的半定量指数。该指数已在前一篇关于授粉媒介风险评估的工作中得到应用，因此验证步骤（采样区域、采集的样本、样本分布）是根据这些生物体的特性和行为进行规划的，并以蜜蜂（Apis mellifera）作为授粉媒介的代表。该指数的开发基于这样一种假设，即暴露不仅取决于农药的环境归宿，还取决于目标生物体的摄食行为（在这种情况下，指的是评估的目标）。该指数已在意大利东北部（威尼托地区）的不同实验区应用和验证，这些实验区的面积为 4×4 公里，具有不同的影响水平。通过评估数据集分辨率对预测效率的影响，对该指数进行了敏感性分析。得到的结果表明，预测浓度与实测浓度之间具有良好的一致性，支持该指数用于改进授粉媒介暴露评估的适用性。
