Advanced analytical techniques based on chromatography for the detection of organic micropollutants in aquatic environments

Motivation: The abundance of organic micropollutants, e.g., Pesticide Residues (RP), Polycyclic Aromatic Hydrocarbons (PAHs), Chlorinated Polybibenyls (PCBs) and Volatile Organic Compounds (VOCs), in aquatic environments poses an environmental and public health threat. Despite the notable advances in analytical chemistry, the identification of organic contaminants in water continues to be a challenge today due to the high number of contaminants that may be present in the samples (Hernández et al., 2015). This problem gives rise to the need to develop analytical methodologies that allow these contaminants to be detected at ng/L levels (Muter & Bartkevics, 2020).Methods Gas chromatography (GC) or liquid chromatography (LC) coupled to mass spectrometry (MS) are the most appropriate techniques for identifying and/or quantifying organic micropollutants in aquatic samples. These techniques allow to monitor the quality of the water in order to comply with the Spanish legislation established in Royal Decree 817/2015, of September 11, which establishes the criteria for monitoring and evaluating the state of surface waters and environmental quality standards.Results: It can be said that these analytical chemistry techniques are capable of unequivocally identifying and quantifying the presence of organic micropollutants in aquatic samples.Conclusions: Gas chromatography (GC) or liquid chromatography (LC) coupled to mass spectrometry (MS) is a reliable analytical technique for the identification and quantification of organic micropollutants in aquatic samples, which allows their monitoring and evaluation based on what is marked by Royal Decree 817/2015, of September 11. However, there is still a need to develop analytical methodologies that are capable of identifying and quantifying a long list of contaminants in a single analytical technique

Changes in the Lower Drava River Water Quality Parameters Over 24 Years

The goal of this study was to analyse 13 physico-chemical and microbiological parameters of the Drava River water at three sampling sites in the lower Drava region (eastern Croatia) over two distinct periods: the pre-war period between 1985 and 1992 and the post-war period between 1993 and 2008. Over both periods, most parameters kept within the tolerable water quality limits, while NO3-N, NH4-N and BOD5 were higher. The lower Drava showed slight organic pollution with high concentrations of dissolved oxygen. High levels of total coliforms and heterotrophic bacteria in the post-war period were only found downstream of the town of Osijek. Upstream of Osijek, the river showed a tendency for improvement.prostornih i vremenskih promjena tijekom perioda od 24 godine. Analizirali smo 13 fi zikalno-kemijskih i mikrobioloških parametara vode rijeke Drave na tri mjerne postaje smještene na području donjeg toka Drave (istočna Hrvatska) tijekom dvaju različitih razdoblja: 1985.-1992. (period prije rata) i 1993.-2008. (period poslije rata). Iako su vrijednosti većine podataka prikupljenih tijekom dvaju promatranih razdoblja oscilirale, vrijednosti su im se još uvijek nalazile u granicama za I. i II. vrstu voda. Vrijednosti nekih fi zikalno-kemijskih varijabla, kao što su NO3-N, NH4-N i BPK5 još su uvijek iznad granice za II. vrstu. Rezultati ovog istraživanja pokazali su blago organsko onečišćenje vode rijeke Drave s visokim koncentracijama otopljenog kisika. Povećanje broja ukupnih koliformnih i heterotrofnih bakterija u poslijeratnom razdoblju veliki je problem u području nizvodno od Osijeka pri čemu njihov broj katkad dostiže i vrijednosti za V. skupinu površinskih voda. Rezultati analize kvalitete vode rijeke Drave u dva različita razdoblja na dva mjerna mjesta uzvodno od Osijeka upućuju na tendenciju poboljšanja, iako neki od promatranih parametara pokazuju vrijednosti više od onih za II. skupinu riječnih voda. Različitosti, odnosno sličnosti među mjernim postajama istražene su metodom klasterske analize