TY - JOUR
T1 - The dissipation and microbial ecotoxicity of tebuconazole and its transformation products in soil under standard laboratory and simulated winter conditions
AU - El Azhari, Najoi
AU - Dermou, Eftychia
AU - Barnard, Romain L.
AU - Storck, Veronika
AU - Tourna, Maria
AU - Beguet, Jérémie
AU - Karas, Panagiotis A.
AU - Lucini, Luigi
AU - Rouard, Nadine
AU - Botteri, Lucio
AU - Ferrari, Federico
AU - Trevisan, Marco
AU - Karpouzas, Dimitrios G.
AU - Martin-Laurent, Fabrice
PY - 2018
Y1 - 2018
N2 - Tebuconazole (TBZ) is a widely used triazole fungicide at EU level on cereals and vines. It is relatively persistent in
soil where it is transformed to various transformation products (TPs) which might be environmentally relevant.
We assessed the dissipation of TBZ in soil under contrasting incubation conditions (standard vs winter simulated)
that are relevant to its application scheme, determined its transformation pathway using advanced analytical
tools and 14C-labeled TBZ and assessed its soil microbial toxicity. Mineralization of 14C-triazole-ring-labeled
TBZ was negligible but up to 11% of 14C-penyl-ring-labeled TBZ evolved as 14CO2 within 150 days of incubation.
TBZ persistence increased at higher dose rates (×10 compared to the recommended agronomical dose ×1) and
under winter simulated conditions compared to standard incubation conditions (at ×1 dose rate DT50 of 202
and 88 days, respectively). Non-target suspect screening enabled the detection of 22 TPs of TBZ, among which
17 were unknown. Mass spectrometry analysis led to the identification of 1-(4-chlorophenyl) ethanone, a novel TP of TBZ, the formation of which and decay in soil was determined by gas chromatography mass spectrometry.
Three hypothetical transformation pathways of TBZ, all converging to 1H-1,2,4-triazole are proposed based on suspect screening. The ecotoxicological effect of TBZ and of its TPs was assessed by measuring by qPCR the abundance of the total bacteria and the relative abundance of 11 prokaryotic taxa and 4 functional groups. A transient impact of TBZ on the relative abundance of all prokaryotic taxa (except α-proteobacteria and Bacteroidetes) and one functionalmicrobial group (pcaH-carryingmicroorganisms)was observed. However the direction of the effect (positive or negative) varied, and in certain cases, depended on the incubation conditions.
Proteobacteria was the most responsive phylum to TBZ with recovery observed 20 days after treatment. The ecotoxicological effects on the soil microorganisms were not correlated with 1-(4-chlorophenyl) ethanone.
AB - Tebuconazole (TBZ) is a widely used triazole fungicide at EU level on cereals and vines. It is relatively persistent in
soil where it is transformed to various transformation products (TPs) which might be environmentally relevant.
We assessed the dissipation of TBZ in soil under contrasting incubation conditions (standard vs winter simulated)
that are relevant to its application scheme, determined its transformation pathway using advanced analytical
tools and 14C-labeled TBZ and assessed its soil microbial toxicity. Mineralization of 14C-triazole-ring-labeled
TBZ was negligible but up to 11% of 14C-penyl-ring-labeled TBZ evolved as 14CO2 within 150 days of incubation.
TBZ persistence increased at higher dose rates (×10 compared to the recommended agronomical dose ×1) and
under winter simulated conditions compared to standard incubation conditions (at ×1 dose rate DT50 of 202
and 88 days, respectively). Non-target suspect screening enabled the detection of 22 TPs of TBZ, among which
17 were unknown. Mass spectrometry analysis led to the identification of 1-(4-chlorophenyl) ethanone, a novel TP of TBZ, the formation of which and decay in soil was determined by gas chromatography mass spectrometry.
Three hypothetical transformation pathways of TBZ, all converging to 1H-1,2,4-triazole are proposed based on suspect screening. The ecotoxicological effect of TBZ and of its TPs was assessed by measuring by qPCR the abundance of the total bacteria and the relative abundance of 11 prokaryotic taxa and 4 functional groups. A transient impact of TBZ on the relative abundance of all prokaryotic taxa (except α-proteobacteria and Bacteroidetes) and one functionalmicrobial group (pcaH-carryingmicroorganisms)was observed. However the direction of the effect (positive or negative) varied, and in certain cases, depended on the incubation conditions.
Proteobacteria was the most responsive phylum to TBZ with recovery observed 20 days after treatment. The ecotoxicological effects on the soil microorganisms were not correlated with 1-(4-chlorophenyl) ethanone.
KW - Dissipation
KW - Microbial ecotoxicology
KW - Tebuconazole
KW - Transformation product
KW - Dissipation
KW - Microbial ecotoxicology
KW - Tebuconazole
KW - Transformation product
UR - http://hdl.handle.net/10807/122967
UR - http://www.elsevier.com/locate/scitotenv
U2 - 10.1016/j.scitotenv.2018.05.088
DO - 10.1016/j.scitotenv.2018.05.088
M3 - Article
SN - 0048-9697
VL - 637-638
SP - 892
EP - 906
JO - Science of the Total Environment
JF - Science of the Total Environment
ER -