MAIN LABORATORY
The Department for Organic Indicator Testing is responsible for the development and application of instrumental methods for detecting organic compounds in surface inland waters and sediment.
Sophisticated instrumental equipment enables the development of selective and highly sensitive methods for the detection and quantification of organic pollutants, in compliance with European and national water management regulations, which demand increasingly lower quantification limits.
Water monitoring is of paramount importance for obtaining a broader understanding of environmental conditions and is crucial for identifying potentially hazardous substances requiring continuous surveillance. The most important policy document for European Union water management is the Water Framework Directive (2000). In line with this directive, a list of priority substances has been compiled, comprising chemical substances and substance groups classified as highly toxic and persistent in the environment, posing a risk to aquatic ecosystems. The revision of the priority substances list allows the European Commission to identify the emergence of new pollutants, which are seen as potential candidates for the list. To accommodate this, a new mechanism called the Watch List has been introduced, which is revised and supplemented every two years.
The Department for Organic Indicator Testing primarily focuses on systematic monitoring of priority substances and priority hazardous substances in order to assess the ecological status of surface inland waters and sediment. It also tracks other pollutants from the Watch List, whose presence in water and sediment may pose potential risks to human health, wildlife, and the environment. The Watch List includes substances from categories such as pesticides, pharmaceuticals, and personal care products.
Through the application of advanced liquid and gas chromatography techniques combined with mass spectrometry, the Department for Organic Indicators Testing tracks more than 400 distinct organic pollutants.
One of the most commonly used analytical methods for the identification and quantification of compounds from the group of pharmaceuticals and pesticides in water environment samples, at very low detection limits, is liquid chromatography coupled with tandem mass spectrometry.
Pharmaceuticals are natural or synthetic compounds used for treating or preventing diseases in humans and animals. The increasing production and consumption of pharmaceuticals have led to their rising presence in water and aquatic ecosystems. Due to their persistence in the environment, their bioaccumulation, and impact on growth and reproduction, pharmaceuticals pose a significant threat to aquatic life.
Pesticides are synthetic chemical compounds classified as toxic substances. While they are designed to eliminate weeds, rodents, and insects, certain pesticides have also been proven to be carcinogenic to humans.
Using an innovative dispersive liquid-liquid microextraction (DLLME) technique, combined with gas chromatography coupled with mass spectrometry, highly sensitive methods have been developed for detecting pesticides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), plasticisers, flame retardants, and tributyltin compounds. Due to their toxicity, 25 compounds from these groups are included in the list of priority and other pollutants in surface waters.
With gas chromatography coupled with tandem mass spectrometry, the Department also determines the presence of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (dioxins). Dioxins predominantly arise as unintended by-products of industrial activities, with no purposeful production. In nature, small amounts of dioxins can be found as by-products of forest fires and volcanic activity. Their emission is primarily linked to waste incineration, the combustion of fuels (such as wood, coal, and oil), chlorine bleaching in the pulp and paper industry, the manufacture of chlorinated pesticides, and the burning of plastics and chlorine-based materials. Dioxins may enter water bodies via atmospheric deposition, soil erosion from contaminated sites, or direct industrial discharges.
Gas chromatography coupled with mass spectrometry is also employed to identify and quantify volatile organic compounds, which have a boiling point below 200°C. The Headspace sampling technique is used to detect these compounds. This method is particularly effective for analysing highly volatile compounds while minimising interference from less volatile or non-volatile sample components. The Headspace method is used to determine aromatic hydrocarbons, such as benzene, toluene, and xylene isomers, which are by-products of the petroleum industry and are also found in coal tar.
All volatile organic compounds are toxic and may enter the human body via inhalation, skin contact, or ingestion.
To support surface water monitoring, Department staff regularly conduct validation of instrumental methods, water and sediment sampling at designated locations, sample preparation and analysis, and data processing.