Determination of organic pollutants in Anguilla anguilla by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS)

Bioaccumulation of Organic and Inorganic Pollutants in Fish from Thermaikos Gulf: Preliminary Human Health Risk Assessment Assisted by a Computational Approach

The monitoring of contaminants in fish species is pivotal for fishes' health and reproduction, as well as for human health. In the specific work, three major categories of contaminants, pesticides, pharmaceuticals, and macro and trace elements, were investigated in two major fish species, Dicentrarchus labrax and Solea solea, collected from Thermaikos Gulf, in Greece. To achieve this goal, three analytical methods using LC-MS/MS, GC-MS/MS, and ICP-MS were developed, validated, and applied to the collected fish samples. The results indicated a very low prevalence of caffeine and acetaminophen, both not exceeding 3.8 μg/kg fish. Similarly, thiabendazole, cypermethrin, and tricyclazole (pesticides) were found in a concentration range of 0.9 to 13.7 μg/kg fish, while in one D. labrax sample, traces of the metabolite of organochlorine pesticide DDT, o,p'-DDE were detected. Al, Mn, Fe, Zn, and Sr were the predominant trace elements in a concentration range of 500-20,000 μg/kg fish. Macro elements levels varied from 280 to 5405 mg/kg fish. Health risk assessment did not unveil an unacceptable risk for the human health of adults, apart from one sample presenting Hg above the regulatory levels. On the contrary, for children, the calculated hazard quotient values for Hg in all cases and for two As detections were higher than the threshold value of 1, indicating a potential risk.

Single injection LC-MS/MS analytical method for the quantification of diverse families of micropollutants, including PFAS and organotins, in Gammarus fossarum

Since the last decades, light has been shed on the pollution of aquatic ecosystems. Considering apolar compounds in water, analysis of the dissolved phase is not sufficient due to their possible bioaccumulation. Additional analysis of sediments, biota, or sentinel species is necessary. Among sentinel species, Gammarus fossarum is a small shrimp of 30 mg that lives naturally in the river. Its ability to bioaccumulate makes it a good bioindicator of river pollution. Nevertheless, micropollutants are difficult to extract from gammarids due to their small size and their high level of lipids. Extracted interferences can lead to analytical difficulties. Targeted micropollutants in this work were organotins, personal and pharmaceutical care products (PPCPs), pesticides, flame retardants, and perfluorinated compounds. A sample preparation based on QuEChERS followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was developed: different salts (acetate and citrate) and purification (addition of hexane, dispersive SPE) were tested and validated. Targeted molecules used to be analyzed by LC-MS/MS, except organotins which are principally analyzed in gas chromatography. One of the main challenges was to quantify them also in LC-MS/MS to implement an original multi-residue method. The analysis of 40 compounds was finally validated according to ICH guidelines, with LOQs ranging from 0.04 ng.g-1 to 313.5 ng.g-1. Regarding Perfluorooctanesulfonic acid (PFOS) and the sum of hexabromocyclododecane, LOQs reached the environmental quality standards in biota which are respectively of 9.1 and 167 ng.g-1. Finally, the method was applied to 15 real samples. Many compounds were quantified: perfluorinated compounds, drugs such as ketoprofen, and even cosmetics products such as octocrylene. This is the first study to quantify as many emerging compounds, especially organotins, in a sentinel species such as G. fossarum.

Automation and Computerization of (Bio)sensing Systems

Sensing systems necessitate automation to reduce human effort, increase reproducibility, and enable remote sensing. In this perspective, we highlight different types of sensing systems with elements of automation, which are based on flow injection and sequential injection analysis, microfluidics, robotics, and other prototypes addressing specific real-world problems. Finally, we discuss the role of computer technology in sensing systems. Automated flow injection and sequential injection techniques offer precise and efficient sample handling and dependable outcomes. They enable continuous analysis of numerous samples, boosting throughput, and saving time and resources. They enhance safety by minimizing contact with hazardous chemicals. Microfluidic systems are enhanced by automation to enable precise control of parameters and increase of analysis speed. Robotic sampling and sample preparation platforms excel in precise execution of intricate, repetitive tasks such as sample handling, dilution, and transfer. These platforms enhance efficiency by multitasking, use minimal sample volumes, and they seamlessly integrate with analytical instruments. Other sensor prototypes utilize mechanical devices and computer technology to address real-world issues, offering efficient, accurate, and economical real-time solutions for analyte identification and quantification in remote areas. Computer technology is crucial in modern sensing systems, enabling data acquisition, signal processing, real-time analysis, and data storage. Machine learning and artificial intelligence enhance predictions from the sensor data, supporting the Internet of Things with efficient data management.

An effective method for the simultaneous extraction of 173 contaminants of emerging concern in freshwater invasive species and its application

A robust and efficient extraction method was developed to detect a broad range of pollutants of emerging interest in three freshwater invasive species: American red crab (Prokambarus clarkii), Asian clam (Corbicula fluminea), and pumpkinseed fish (Lepomis gibbosus). One native species, "petxinot" clam (Anodonta cygnea), was also evaluated. Invasive species are often more resistant to contamination and could be used in biomonitoring studies to assess the effect of contaminants of emerging concern on aquatic ecosystems while preserving potentially threatened native species. So far, most extraction methods developed for this purpose have focused on analyzing fish and generally focus on a limited number of compounds, especially analyzing compounds from the same family. In this sense, we set out to optimize a method that would allow the simultaneous extraction of 87 PhACs, 11 flame retardants, 21 per- and poly-fluoroalkyl substances, and 54 pesticides. The optimized method is based on ultrasound-assisted solvent extraction. Two tests were performed during method development, one to choose the extraction solvent with the best recovery efficiencies and one to select the best clean-up. The analysis was performed by high-performance liquid chromatography coupled to high-resolution mass spectrometry. The method obtained recoveries between 40 and 120% and relative standard deviations of less than 25% for 85% of the analytes in the four validated matrices. Limits of quantification between 0.01 ng g-1 and 22 ng g-1 were obtained. Application of the method on real samples from the Albufera Natural Park of Valencia (Spain) confirmed the presence of contaminants of emerging concern in all samples, such as acetaminophen, hydrochlorothiazide, tramadol, PFOS, carbendazim, and fenthion. PFAS were the group of compounds with the highest mean concentrations. C. fluminea was the species with the highest detection frequency, and P. clarkii had the highest average concentrations, so its use is prioritized for biomonitoring studies.

An Overview of Analytical Methods to Determine Pharmaceutical Active Compounds in Aquatic Organisms

There is increasing scientific evidence that some pharmaceuticals are present in the marine ecosystems at concentrations that may cause adverse effects on the organisms that inhabit them. At present, there is still very little scientific literature on the (bio)accumulation of these compounds in different species, let alone on the relationship between the presence of these compounds and the adverse effects they produce. However, attempts have been made to optimize and validate analytical methods for the determination of residues of pharmaceuticals in marine biota by studying the stages of sample treatment, sample clean-up and subsequent analysis. The proposed bibliographic review includes a summary of the most commonly techniques, and its analytical features, proposed to determine pharmaceutical compounds in aquatic organisms at different levels of the trophic chain in the last 10 years.