Pesticides are a highly important environmental problem because of their toxicity and widespread use worldwide, and also because their waste could eventually contaminate various media (soil, water, air, food) that could finally affect the development of life, especially human life. For this reason, the European Union has set very strict limits as regards the amount of waste that can be found in water and food for human consumption. Scientists have, therefore, had to develop very precise analysis techniques in order to detect the hundreds of different pesticides that are used in agriculture.
However, most control programmes for these pollutants only focus on unaltered pesticides, even though several compounds, which are derived from the environmental degradation of these relatively persistent and toxic pesticides (transformation products in scientific jargon), are known This deficit of information on the presence of transformation products in the environment is mainly due to the lack of an analytical method that is able to detect them. María Ibáñez’s work meets this need.
The method consists in combining two already existing chemical analysis techniques: liquid chromatography and mass spectrometry. To check their combined potential, Ibáñez exposed a certain group of pesticides to ultraviolet radiation. In this way, she simulated the effect that sunlight exerts on pesticides in the environment (photodegradation) in the laboratory. The global purpose was to determine which compounds the original phytosanitary product was transformed into. To this end, she combined liquid chromatography and mass spectrometry with quadrupole time–of-flight analysers.
Once the transformation products had been identified under lab conditions, the second part of the study consisted in developing an additional method which would allow to determine the presence or absence of these compounds in the environment, as well as to quantify their levels. To this end, Ibáñez used the same method but she used a triple-quadrupole analyser on this occasion.
After analysing water samples (both surface and underground) taken from various points of the Valencian Community, Ibáñez and her collaborators detected the presence of some of these transformation products.
The study has also allowed us to see the magnitude of the problem generated by the degradation of pesticide waste in soil and water, a facet of the environmental problem of phytosanitary products to which no special attention has been paid to date. “It is worth mentioning that the detection frequency of transformation products, elucidated in relation with intact pesticides, has increased and is, in many cases, higher than the concentration levels in the products themselves”, indicates María Ibáñez in her thesis.
A question that still had to be clarified was whether the new method would be able to also identify transformation products of pesticides in living organisms. Therefore, in vitro experiments with microsomes (cell cultures) and in vivo experiments with rats were conducted in collaboration with UJI’s Department of Psychobiology. Once more, the potential of this technique was evidenced, this time in the field of biology.
“Coupling liquid chromatography with mass spectrometry by using triple-quadrupole and quadrupole time-of-flight analysers has proved to be a powerful analytical tool for the identification, quantification and confirmation of transformation products and pesticide metabolites in environmental and biological samples”, María Ibáñez explains. With her work, Ibáñez opens the way forward to future studies not only on these compounds but, above all, on their effects on human health. And all this thanks to her verification of an analytical method that can detect them and can quantify these compounds.
The study of this researcher at UJI’s Institute of Pesticides and Waters has been directed by Félix Hernández and Juan Vicente Sancho, scientists from this Institute, and has been published in the form of scientific papers in international journals such as Analytical Chemistry, Analytical and Bioanalytical Chemistry, Journal of Chromatography A, Trends in Analytical Chemistry and Rapid Communications in Mass Spectrometry.
Hugo Cerdà | alfa
Climate change, population growth may lead to open ocean aquaculture
05.10.2017 | Oregon State University
New machine evaluates soybean at harvest for quality
04.10.2017 | University of Illinois College of Agricultural, Consumer and Environmental Sciences
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research