FN Archimer Export Format
PT J
TI The influence of natural dissolved organic matter on herbicide toxicity to marine microalgae is species-dependent
BT 
AF COQUILLE, Nathalie
   MENARD, Dominique
   ROUXEL, Julien
   DUPRAZ, Valentin
   EON, Melissa
   PARDON, Patrick
   BUDZINSKI, Helene
   MORIN, Soizic
   PARLANTI, Edith
   STACHOWSKI-HABERKORN, Sabine
AS 1:1,2,3,4;2:1;3:1;4:1,5;5:2;6:3,4;7:3,4;8:2;9:3,4;10:1;
FF 1:PDG-RBE-BE-LEX;2:PDG-RBE-BE-LEX;3:PDG-RBE-BE-LEX;4:;5:;6:;7:;8:;9:;10:PDG-RBE-BE-LEX;
C1 Ifremer, Lab Ecotoxicol, Rue Ile Yeu,BP 21105, F-44311 Nantes 03, France.
   Irstea, UR EABX, Ctr Bordeaux, 50 Ave Verdun, F-33612 Cestas, France.
   Univ Bordeaux, UMR CNRS 5805, EPOC, LPTC, 351 Cours Liberat,CS 10004, F-33405 Talence, France.
   CNRS, UMR 5805, EPOC, LPTC, 351 Cours Liberat,CS 10004, F-33405 Talence, France.
   Univ Nantes, UFR Sci & Tech, 2 Rue Houssiniere,BP 92208, F-44322 Nantes 03, France.
C2 IFREMER, FRANCE
   IRSTEA, FRANCE
   UNIV BORDEAUX, FRANCE
   CNRS, FRANCE
   UNIV NANTES, FRANCE
SI NANTES
SE PDG-RBE-BE-LEX
IN WOS Ifremer jusqu'en 2018
   copubli-france
   copubli-p187
   copubli-univ-france
IF 3.794
TC 17
UR https://archimer.ifremer.fr/doc/00428/53964/55113.pdf
LA English
DT Article
DE ;Microalgae;Herbicides;Natural dissolved organic matter;DOM;Toxicity;Interactions
AB Microalgae, which are the foundation of aquatic food webs, may be the indirect target of herbicides used for agricultural and urban applications. Microalgae also interact with other compounds from their environment, such as natural dissolved organic matter (DOM), which can itself interact with herbicides. This study aimed to evaluate the influence of natural DOM on the toxicity of three herbicides (diuron, irgarol and S-metolachlor), singly and in ternary mixtures, to two marine microalgae, Chaetoceros calcitrans and Tetraselmis suecica, in monospecific, non-axenic cultures. Effects on growth, photosynthetic efficiency (Ф’M) and relative lipid content were evaluated. The chemical environment (herbicide and nutrient concentrations, dissolved organic carbon and DOM optical properties) was also monitored to assess any changes during the experiments. The results show that, without DOM, the highest irgarol concentration (I0.5: 0.5 mg L−1) and the strongest mixture (M2: irgarol 0.5 μg L−1 + diuron 0.5 μg L−1 + S-metolachlor 5.0 μg L−1) significantly decreased all parameters for both species. Similar impacts were induced by I0.5 and M2 in C. calcitrans (around −56% for growth, −50% for relative lipid content and −28% for Ф’M), but a significantly higher toxicity of M2 was observed in T. suecica (−56% and −62% with I0.5 and M2 for growth, respectively), suggesting a possible interaction between molecules. With DOM added to the culture media, a significant inhibition of these three parameters was also observed with I0.5 and M2 for both species. Furthermore, DOM modulated herbicide toxicity, which was decreased for C. calcitrans (−51% growth at I0.5 and M2) and increased for T. suecica (-64% and −75% growth at I0.5 and M2, respectively). In addition to the direct and/or indirect (via their associated bacteria) use of molecules present in natural DOM, the characterization of the chemical environment showed that the toxic effects observed on microalgae were accompanied by modifications of DOM composition and the quantity of dissolved organic carbon excreted and/or secreted by microorganisms. This toxicity modulation in presence of DOM could be explained by (i) the modification of herbicide bioavailability, (ii) a difference in cell wall composition between the two species, and/or (iii) a higher detoxification capacity of C. calcitrans by the use of molecules contained in DOM. This study therefore demonstrated, for the first time, the major modulating role of natural DOM on the toxicity of herbicides to marine microalgae. 
PY 2018
PD MAY
SO Aquatic Toxicology
SN 0166-445X
PU Elsevier Science Bv
VL 198
UT 000430630100011
BP 103
EP 117
DI 10.1016/j.aquatox.2018.02.019
ID 53964
ER

EF