Periodic Reporting for period 1 - EnvFate (Study of the environmental impact of insecticides by metabolomic foot-printing approach)
Período documentado: 2017-09-01 hasta 2019-08-31
"Introduction: Mosquitoes can carry infectious diseases from person to person and from place to place. Presence and establishment of invasive mosquito species such as Aedes aegypti and Aedes albopictus are rapidly increasing in the European environment. Mostly due to the increase of international exchanges (rapid movement of people infected with the virus and competent mosquito vectors), urbanisation (high density of susceptible people, a plethora of mosquito breeding sites), and the global warming (eg, the capacity of mosquitoes to transmit the virus is heavily dependent on temperature). Indeed, the presence of mosquito vectors can create a risk of an epidemic such as dengue, chikungunya or more recently the Zika virus. Sustainable vector management is the only means that effectively could prevent and control the transmission of the viruses of public health importance.
State-of-the-art: Since the appearance of the European Directive (98/8/CE) in 1998 concerning the marketing authorizations of biocides, the use of the synthetic insecticides has reconsidered. Indeed, it forbids, since September 2006, the use of non-approved synthetic products. Therefore, this Directive led to the increasing use of biological insecticides such as toxins (cry proteins) produced by the bacterium Bacillus thuringiensis israelensis (Bti) that kills mosquito larvae upon ingestion. Thus higher mosquito population leads to higher use of Bti that ultimately builds anthropogenic burden in the southernmost part of Europe.
Objectives and overview of the action: Being a natural product, Bti producing insecticidal Cry proteins has largely assumed as ""Environment-friendly"" and that it does not have any negative influence on the environment. Does Bti is so harmless? To our knowledge, the environmental fate and impact of this biological substance are poorly studied and this is the objective of the proposed project. This study is important at the environmental level as the presence of emerging pollutants in the different environments is nowadays one of the major concerns and is of critical importance to regulatory authorities. Although Bti is not yet identified as an emerging pollutant, environmental protection associations have already pointed out the overuse of this biocide for invasive mosquito population control. Besides studying Bti, we also examined one chemical insecticide for comparison. We chose α-cypermethrin as it is still a lot used as an insecticide in the rice field treatments.
Environmental Metabolomic Footprinting (EMF) approach: EMF consists of the metabolomic data acquisition (through LC-MS) and data processing via the use of multivariate statistical analysis. We employed EMF to know the impact of both insecticides on the sediment, their resilience time, and on longer-term evidence the potential pollution biomarkers (overexpression of sediment endogenous compounds, transformation products,…). In parallel to the metabolomic analysis, a study on the presence of a mixed microbial community in the test sediments is underway using a metabarcoding approach. The metabarcoding analysis will allow evaluating the microbial community responses to the Bti and therefore to evaluate its eco-toxicity. The use of omics approaches (metabarcoding and metabolomics) applied to the sediment matrix is an innovative ecotoxicology assessment tool. It has the potential to allow the identification of potential Bti associated biomarkers.
Conclusions:
The conclusions of the action cannot be yet described completely as some aspects are still under evaluation. Our findings from metabolomics data suggest that the EMF approach offers to monitor changes in the meta-metabolome of the sediment after Bti and α-cypermethrin treatment. It also provides a time-dependent metabolic profile of contaminated sediment samples to evaluate the resilience time of the sediment."
State-of-the-art: Since the appearance of the European Directive (98/8/CE) in 1998 concerning the marketing authorizations of biocides, the use of the synthetic insecticides has reconsidered. Indeed, it forbids, since September 2006, the use of non-approved synthetic products. Therefore, this Directive led to the increasing use of biological insecticides such as toxins (cry proteins) produced by the bacterium Bacillus thuringiensis israelensis (Bti) that kills mosquito larvae upon ingestion. Thus higher mosquito population leads to higher use of Bti that ultimately builds anthropogenic burden in the southernmost part of Europe.
Objectives and overview of the action: Being a natural product, Bti producing insecticidal Cry proteins has largely assumed as ""Environment-friendly"" and that it does not have any negative influence on the environment. Does Bti is so harmless? To our knowledge, the environmental fate and impact of this biological substance are poorly studied and this is the objective of the proposed project. This study is important at the environmental level as the presence of emerging pollutants in the different environments is nowadays one of the major concerns and is of critical importance to regulatory authorities. Although Bti is not yet identified as an emerging pollutant, environmental protection associations have already pointed out the overuse of this biocide for invasive mosquito population control. Besides studying Bti, we also examined one chemical insecticide for comparison. We chose α-cypermethrin as it is still a lot used as an insecticide in the rice field treatments.
Environmental Metabolomic Footprinting (EMF) approach: EMF consists of the metabolomic data acquisition (through LC-MS) and data processing via the use of multivariate statistical analysis. We employed EMF to know the impact of both insecticides on the sediment, their resilience time, and on longer-term evidence the potential pollution biomarkers (overexpression of sediment endogenous compounds, transformation products,…). In parallel to the metabolomic analysis, a study on the presence of a mixed microbial community in the test sediments is underway using a metabarcoding approach. The metabarcoding analysis will allow evaluating the microbial community responses to the Bti and therefore to evaluate its eco-toxicity. The use of omics approaches (metabarcoding and metabolomics) applied to the sediment matrix is an innovative ecotoxicology assessment tool. It has the potential to allow the identification of potential Bti associated biomarkers.
Conclusions:
The conclusions of the action cannot be yet described completely as some aspects are still under evaluation. Our findings from metabolomics data suggest that the EMF approach offers to monitor changes in the meta-metabolome of the sediment after Bti and α-cypermethrin treatment. It also provides a time-dependent metabolic profile of contaminated sediment samples to evaluate the resilience time of the sediment."
To achieve the goal proposed in the ENVFATE project, five different 300-day long experiments have been set up. This set-up has based on previous experience with short-term experiments. We performed the optimized experiments in controlled climatic chambers to mimic the natural conditions. Besides, insecticide dose and sampling time points have reconsidered. We used separate microcosm for three different sediments as a model for the study. In all experiments, microcosms have treated separately with Bti or α-cypermethrin or water and monitored for the dissipation profile of insecticides at selected time intervals by LC-HRMS analysis. These experiments significantly advanced our knowledge of how different insecticides follow different dissipation according to different sediment types. Most importantly, it also enables us to understand the complexity of analyzing samples directly from the environment. Ion suppression is one of the issues we have identified that will help to improve the reliable interpretation of the mass spectrometry-based analysis. In-details analysis of large datasets is currently underway. In other experiments, we are determining the change in the microbial community for different insecticide treatments. We are also cross-validating our observation from the LC-HRMS platform with NMR platform.
So far, the results have been disseminated as follows.
Professional audiences:
Poster: CloudMet2017,11-15 Sept 2017 Pula,Italy
Poster: 5th MCAA Annual Conference and General Assembly, 2-3 February 2018, Leuven, Belgium
INVITED ORAL: Workshop on Environmental and socioeconomic effects of Bti mosquito control. 26-28 March 2018, Kurhaus Annweiler, Germany
Oral: RFMF 2018, 23-26May 2018, Liege, Belgium
Poster & Flash presentation: European Science Open Forum 2018, 9-14 July 2018, Toulouse France
Oral: Natural Products and Biocontrol, 25-28 September 2018, Perpignan, FRANCE
General Public:
Fête de la science, University of Perpignan Via Domitia, 11-13 October 2018
Media:
Pythagoras' Trousers: Weekly science & technology magazine show from The IET, broadcast on Radio Cardiff.
Scientific articles are in preparation.
So far, the results have been disseminated as follows.
Professional audiences:
Poster: CloudMet2017,11-15 Sept 2017 Pula,Italy
Poster: 5th MCAA Annual Conference and General Assembly, 2-3 February 2018, Leuven, Belgium
INVITED ORAL: Workshop on Environmental and socioeconomic effects of Bti mosquito control. 26-28 March 2018, Kurhaus Annweiler, Germany
Oral: RFMF 2018, 23-26May 2018, Liege, Belgium
Poster & Flash presentation: European Science Open Forum 2018, 9-14 July 2018, Toulouse France
Oral: Natural Products and Biocontrol, 25-28 September 2018, Perpignan, FRANCE
General Public:
Fête de la science, University of Perpignan Via Domitia, 11-13 October 2018
Media:
Pythagoras' Trousers: Weekly science & technology magazine show from The IET, broadcast on Radio Cardiff.
Scientific articles are in preparation.
We have shared our valuable inputs with EFSA to support metabolomics as an interesting tool to assess environmental risks in the field of food safety. At the European level, the results obtained in our project could be integrated with the ENDURE network. The ENDURE network has started its activities in 2007 with the financial support of the European Commission (FP6) and it is now established as a permanent self-sustaining network of established research institutes, universities and extension organizations for knowledge exchange regarding all aspects of integrated pest management (IPM). Secondly, we will also share our scientific findings of omics based insecticide risk assessment with the European Centre for Ecotoxicology and Toxicology of Chemicals (http://www.ecetoc.org/). ECOTOC is a forum for expert collaboration from world-wide industry, academia and regulatory bodies who work together to develop an agreed understanding on how the State of the Science can be used to improve Risk Assessment by developing novel Tools, Guidance and Frameworks. The development of such applications/guidelines was not within the scope of this project but they will benefit from this project's results.