Open AccessImpacts of (Nano)formulations on the Fate of an Insecticide in Soil and Consequences for Environmental Exposure Assessment
Author(s) -
Mélanie Kah,
Anne-Kathrin Weniger,
Thilo Hofmann
Publication year - 2016
Publication title -
environmental science and technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.851
H-Index - 397
eISSN - 1520-5851
pISSN - 0013-936X
DOI - 10.1021/acs.est.6b02477
Subject(s) - active ingredient , context (archaeology) , sorption , pesticide , environmental science , environmental chemistry , ingredient , soil water , groundwater , chemistry , biochemical engineering , toxicology , soil science , food science , engineering , ecology , biology , adsorption , paleontology , bioinformatics , geotechnical engineering , organic chemistry
The development of nanopesticides has recently received an increased level of attention. However, there are very few data about the environmental fate of these new products, and it is not known whether nanoformulations can be evaluated within the current pesticide regulatory framework. Sorption and degradation parameters of the insecticide bifenthrin were measured in two soils for (i) the pure active ingredient, (ii) three nanoformulations, and (iii) a commercially available formulation. In most cases, fate parameters derived for the nanopesticides were significantly different from those derived for the pure active ingredient (factors of up to 10 for sorption and 1.8 for degradation), but discrepancies were not easy to relate to the characteristics of the nanocarriers. In some cases, differences were also observed between the commercial formulation and the pure active ingredient (factors of up to 1.4 for sorption and 1.7 for degradation). In the regulatory context, the common assumption that formulations do not influence the environmental fate of pesticide active ingredients after application seems therefore not always adequate. In the absence of direct measurement, an inverse modeling approach was successfully applied to evaluate the durability of the formulations in soil (release half-life ranged between 11 and 74 days). Predicted groundwater concentrations very much depended on the modeling approach adopted but overall suggest that the nanoformulations studied could reduce losses to groundwater.