Development of a soil exposure assessment for plant protection products in Brazil: Requirements, options, and recommendations.

The Brazilian Environmental Authority (IBAMA) has recently identified soil organisms as a priority area for risk assessment development for plant protection products. This includes consideration of which species in soil fauna are important to be tested for risk assessment purposes, which ecotoxicological tests should be used, and which exposure models would be suitable, considering Brazilian soils, local agricultural practices, and local biodiversity. In this brief communication, we present proposals and recommendations for the selection of appropriate regulatory exposure assessment techniques to support initial or foundation tier assessment.

Mobility in the context of exposure-based assessment of chemicals for drinking water resource protection.

In order to protect European Union (EU) drinking water resources from chemical contamination, criteria for identifying persistent, mobile, and toxic (PMT) chemicals and very persistent and very mobile (vPvM) chemicals under the EU REACH Regulation were proposed by the German Environment Agency (Umweltbundesamt-UBA). Additionally, new hazard classes for PMT and vPvM substances in the revised EU classification, labeling, and packaging (CLP Regulation) are intended. Therefore, a reliable approach in the identification of potential drinking water resource contaminants is needed.

Modelling approaches to compare sorption and degradation of metsulfuron-methyl in laboratory micro-lysimeter and batch experiments.

Results of laboratory batch studies often differ from those of outdoor lysimeter or field plot experiments--with respect to degradation as well as sorption. Laboratory micro-lysimeters are a useful device for closing the gap between laboratory and field by both including relevant transport processes in undisturbed soil columns and allowing controlled boundary conditions. In this study, sorption and degradation of the herbicide metsulfuron-methyl in a loamy silt soil were investigated by applying inverse modelling techniques to data sets from different experimental approaches under laboratory conditions at a temperature of 10 degrees C: first, batch-degradation studies and, second, column experiments with undisturbed soil cores (28 cm length x 21 cm diameter).