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Medical azole antifungals are major compounds used to prevent and to treat invasive aspergillosis (IA). Azole fungicides, called DMI (14-alpha demethylase inhibitors), are also widely used for crop protection and have been reported to be linked to azole-resistant A. fumigatus (aR-Af) development in the environment. The aim of this study was to determine whether or not market gardens that spray DMIs in Eastern France are also affected by the presence of aR-Af. Forty aR-Afs were detected in soils in only two of the four market gardens using DMIs, with 23% (7/30) and 10% (3/30) of soils containing aR-Af. A total of 87.5% of these isolates had the TR34/L98H mutation and 22.5% the TR46/Y121F/T289A mutation on the cyp51A gene. Analyses of residual azole concentrations in soils showed the presence of difenoconazole for up to 2 years after spraying, but only in soils of market gardens where aR-Af was detected. It is very important to identify professional activities that could lead to aR-Af development and to develop preventive measures for at-risk patients living near professional activities using DMIs. We have to better understand why, in some cases, the use of DMI is not linked to aR-Af. Measures should be taken to avoid the use of DMI conferring cross-resistance to preserve the efficiency of human therapeutics.

Amphipods from the genus Gammarus are among the most frequently used organisms in ecotoxicological testing and in situ bioindication. Because of their importance in risk assessment, it is necessary to understand the potential roles of life stage, population source and inter-specific differences on the sensitivity of these organisms to contaminants. In the present study, the acute toxicity of deltamethrin, a commonly used pyrethroid insecticide, has been tested for Gammarus fossarum and Gammarus pulex (Crustacea, Amphipoda) to document the inter- and intra-specific variability at different developmental stages. Adult G. fossarum were about two-fold more sensitive to deltamethrin than adult G. pulex, 96-h LC50 being 33.2 and 68.0 ng L(-1), respectively. However, in the same species, significant differences of sensitivity were observed between individuals from different locations. Furthermore, G. fossarum from certain localities were less sensitive to deltamethrin than certain G. pulex. In addition, juveniles of both species were about 14- to 22-fold more sensitive to deltamethrin than adults: 48-h LC50 in G. fossarum and G. pulex juveniles were 4.0 and 5.7 ng L(-1). Therefore, lethal effects of deltamethrin on Gammarus sp. populations likely depend more on juvenile response rather than on adult response. Since juveniles were also the most abundant population component, the present results show that risk assessment should consider at this developmental stage., (Copyright (c) 2010 Elsevier Inc. All rights reserved.)