Progetto comune di ricerca

Implementazione di metodi in fluorescenza totale e validazione attraverso metodi cromatografici specifici per la misura di residui di pesticidi nei suoli agricoli e nelle acque in Marocco e in Italia

Responsabili di progetto
Luisa Patrolecco, Saadia Ait Lyazidi
Accordo
MAROCCO - CNRST - Centre National pour la Recherche Scientifique et Technique
Bando
CNR/CNRST 2016-2017
Dipartimento
Scienze del sistema terra e tecnologie per l'ambiente
Area tematica
Scienze del sistema Terra e tecnologie per l'ambiente
Stato del progetto
Nuovo

Proposta di ricerca

Every year about 2.5 million tonnes of synthetic pesticides are released worldwide, mainly for agricultural use; 40% is represented by herbicides, sales of which far exceed those of insecticides and fungicides. Ispra (Institute for the Protection and Environmental Research) published a report indicating that Italy is the largest consumer of pesticides per unit area cultivated in Western Europe, with a consumption of 5.6 kg per hectare each year, double than those of France and Germany. 175 active pesticides were found in Italian surface and groundwaters. In particular, significantly increased is the presence of fungicides and insecticides, especially in groundwater. In surface waters (2011-2012) were found pesticide residues in 55.5% of 1,469 sampling points, in 17.2% of cases with concentrations exceeding the limits set by the Environmental Quality Standards (EQS). In groundwater were contaminated 31.8% of 2,404 sampling points, in 6.3% of cases with concentrations exceeding the legal limits. The report states that many substances, about 200, currently in use are not included in monitoring programs, although 44 of these are classified as dangerous by the WFD. In the case of Morocco, the average annual import of pesticides is about 12,000 tons (Maroc 2013), and direct users of these products are poorly savy workers. In addition to this, the invasion by locusts, from southern countries, requiring massive use of insecticides remains a potential threat. Moreover, scientific investigations on the impact of pesticides focus principally on acute intoxication. Nevertheless, although long-term chronic intoxications by pesticide residues through air, soil, or water are the most dangerous threats, the last experimental investigation on the evaluation of soil and water contamination by these pollutants dates back to 2006 (El Bakouri 2006). Therefore, a continuous monitoring of the different environmental compartments (soil, water, and air) is increasingly needed for all the Moroccan territory to help environmental authorities meet this challenge.
In this contest, the purpose of this research is to develop a direct spectrometric approach to monitor soils and waters, at a lower cost than the widely used chromatographic techniques; a spectrometric approach that is effective, reliable, fast, easy to implement and without any use of organic solvents whose utilization is subject to law limitation. The goal is the elaboration of a universal on-line spectral database related to fluorescent pesticides. It is the first time that a catalogue of total excitation-emission and total synchronous fluorescence maps enriched by optimal synchronous spectra, constituting spectral fingerprints of fluorescent pesticides, will be created, enlarged and updated over the time. These multi-components fingerprints must allow the identification of fluorescent pesticides residues in soils, sediments and waters, avoiding thus the systemic recourse to the chromatographic techniques whose use might be reserved only for laboratory accurate analyses and statutory inspection. This approach may be also convenient for on-site continuous monitoring of agricultural soils and neighboring waters; it could be suitable as an alert method in case of massive contamination by fluorescent pesticides. Indeed the applicability of luminescence methods to environmental pollution assessments is increasing with the current availability of compact and portable instruments.This methodological approach will be validated through specific chromatographic metodologies, that wil be performed in Italian laboratories.The main aim of the present investigation is to create a complete total excitation-emission and total synchronous fluorescence mapping database to fingerprint those fluorescent pesticides in large use in Morocco and in Italy. These fluorimetric fingerprints must allow the direct identification of any targeted fluorescent pesticide, persisting in soil or water, without the use of any organic solvent and without extraction or pre-concentration steps. Total excitation-emission fluorescence matrices (TEEMs) and total synchronous fluorescence mappings (TSFMs) make it possible to identify remains of fluorescent pesticides in soils or waters. In order to validate all tests of applicability of the spectral database previously described, IRSA-CNR laboratory will complement the CNRST activities through the optimization of specific chromatographic analytical methods for the determination of selected target compounds. Most commonly methods for the detection and determination of Persistent Organic Pollutants (POPs), such as pesticides (i.e. organochlorine pesticides, triazine pesticides etc.) in environmental matrices include an extraction step, followed by a pre-cleaning step and, finally, followed by a selective chromatographic analysis. In this specific case, soil samples potentially polluted, will be analysed for pesticides content by a preliminary extraction phase involving Accelerated Solvent Extraction (ASE) or Soxhlet extraction with the opportune solvent or mixing of solvents. The final extrat will be analysed by chromatography.
Field investigations consisting in: i) pre-surveys among agricultural operators (distributors, farmers and workers) to target those pesticides in large use in italy and Morocco, ii) collection of samples of homologated pesticides from different operators and iii) sampling campaigns of soils and/or surface waters carried out in selected agricultural areas of Italy (northern region) and Morocco (nearby Meknes). According to this, field investigations of the present project must permit to explore farmers 'attitudes towards farming practices as well as the use of pesticides and their impact on environmental compartments.This joint project is an opportunity to create a framework of partnership in which both of the Moroccan and the Italian teams realize complementary works through the use of completely different technologies.

Obiettivi della ricerca

Currently,chromatographic methods such as GC or HPLC coupled to different detectors (e.g., UV-FL, MS, FID-ECD) are used through the international scientific community to determine the concentration of pesticide residues in soils or waters. In spite of their high accuracy, these chromatographic approaches require sophisticated instrumentations and usually include extraction and/or pre-concentration steps known to be time consuming and involving the use of organic solvents whose utilization is subject to law limitation. Consequently, these sophisticated and expensive techniques can be reserved only for laboratory accurate analyses and statutory inspection.
The main objective of this activity, already underway, is the rapid continuous, reliable and inexpensive monitoring of the levels of organic pollution, by pesticide residues, in agricultural soils and neighboring waters.
It is aimed to create a complete total excitation-emission and total synchronous fluorescence mapping database to fingerprint those fluorescent pesticides in large use in Morocco and in Italy, through the direct identification of any targeted fluorescent pesticide, persisting in soil or water, without the use of any organic solvent and without extraction or preconcentration steps. Total excitation-emission fluorescence matrices (TEEMs) and total synchronous fluorescence mapping (TSFMs) techniques will be validated for pesticides analysis through specific chromatographic analytical methods (GC-MS or LC-MS).

Ultimo aggiornamento: 02/11/2024