Projects / Programmes
Improved treatment and monitoring of Water Framework Directive priority pollutants
| Code |
Science |
Field |
Subfield |
| 1.08.00 |
Natural sciences and mathematics |
Control and care of the environment |
|
| Code |
Science |
Field |
| T270 |
Technological sciences |
Environmental technology, pollution control |
| Code |
Science |
Field |
| 1.05 |
Natural Sciences |
Earth and related Environmental sciences |
WFD, emerging contaminants, pharmaceutical, bisphenol, environmental chemistry, toxicity, monitoring, wastewater, treatment, surface water
Researchers (26)
Organisations (7)
Abstract
Emerging environmental pollutants are substances that have often long been in the environment, but whose presence and significance are only now being elucidated. They commonly derive from municipal and industrial wastewater (WW) sources and are of concern due to possible adverse effects on humans and non-target organisms. In Europe, the Water Framework Directive (WFD, 2000) established the legal basis for protecting and restoring clean water and lists 33 priority substances to be monitored and controlled in surface waters. In 2011 a further 15 chemicals were added to its “watch list”. These include, for the first time, three pharmaceuticals: the anti-inflammatory drug diclofenac (DF) and two steroid hormones: 17β-estradiol (E2) and 17α-ethinylestradiol (EE2). Other emerging pollutants like bisphenol A (BPA) and its alternatives (bisphenols, BP) are expected to follow.
Wastewater treatment plants (WWTP) are the primary source of micropollutants in natural waters and the deficiency in our ability to properly monitor these compounds and remove them completely from WW leaves a significant gap in our knowledge regarding their fate and effects. Data concerning DF, E2 and EE2 in natural waters and WW exists, but current analytical methods do not reach the environmental quality standards (EQS) and limits of quantification (LOQ) demanded by the WFD. Conventional WWTP are designed to remove solids, organic matter and nutrients from WW and are limited in their ability to remove non-target pharmaceutical residues. Conventional biological treatment yields poor and inconsistent removal of DF (avg. 30%). For E2 and EE2 between 75-90% is removed by either (bio)degradation or adsorption onto solid particles, but despite this higher removal efficiency and dilution upon entering surface waters, residual levels can still be high enough to pose a risk and exceed annual average surface water concentrations as defined by the WFD. For emerging contaminants like BPA alternatives analytical methods are yet to be developed and validated.
The proposed project attempts to address these problems by developing an efficient and practical way to monitor average concentrations of the three priority substances and selected emerging contaminants (e.g. bisphenols) in natural waters. First, we will develop ultra-trace level analytical methods (sub ng/L) combining traditional sampling methods and state-of-the-art passive sampling (PS) for polar or hydrophobic organic chemicals. Both methods will yield average compound concentrations over a specific time period as demanded by the WFD. We will then apply optimised analytical procedures to Slovenian surface and ground waters and collect data systematically over a period of one year to test for seasonal variations and to update the existing database on selected emerging contaminants.
The proposals second objective is to explore alternative WW treatments technologies to prevent emerging contaminant residues from entering the environment including advanced biological treatment, photocatalysis and cavitation, which we have already shown to be effective. We will then use the data to optimise our current lab-scale reactor design before upgrading the developed treatments to pilot-scale and finally to full-scale at our collaborating WWTPs. The efficiency of treatment will be evaluated on parent compound removal, formation of stable toxic transformation products and change in toxicity between WW effluent and influent.
This project has the following elements of novelty: the application of passive sampling in WFD monitoring, using cavitation/UV/TiO2 for the removal of micropollutants and sequential treatment including biological treatment, photocatalysis and cavitation. The high applicability of this project is shown by having 3 co-financiers, 5 end-users and 3 international research institutions who have signed an “Expression of interest for collaboration”. All our partners have excellent references, the equipment and have suc
Significance for science
Compounds selected for this proposal are WFD priority substances, which is an indicator of their potential harmful effects and the urgent need to monitor and prevent them from entering the environment. We expect other potentially toxic organic micropollutants, e.g. other pharmaceuticals and bisphenols, will follow these examples. Initially, we will perform a systematic monitoring programme to provide a clear picture of their presence in Slovene waters. There are some studies in this field, mostly made by our laboratory, but the data remain insufficient and involve only a limited number and WWTP size and configurations involved. In addition to traditional sampling, we will deploy passive samplers to see if they really can be a novel, cost-effective and user-friendly monitoring tool that will yield time weighted average (TWA, WFD). The second phase will involve improving the efficiency of existing treatment technologies. Published studies show how DF is recalcitrant to conventional wastewater treatment process and to date there is no technology that shows a consistently high removal of this compound and we aim to address this problem by improving its removal efficiency using advanced treatment technologies. The available literature on hormone removal shows their higher and consistent removal during conventional wastewater treatment, but the high estrogenic potential of these compounds means even reduced levels in receiving surface bodies can have possible detrimental effects. For emerging contaminants like BPA alternatives analytical methods are yet to be developed and validated. Due to possible toxic effects these compounds could have in the environment, an urgent demand exists to find cost-effective technologies for their complete removal or elimination to sufficiently benign levels. The attempt to include cavitation in combination with UV/TiO2 in treatment sequence for removal of emerging contaminants is rather novel. We expect that our research will contribute towards developing such technologies that can be coupled to a conventional wastewater treatment process, which will be an original and highly applicable result.
The project combines research in environmental analytical chemistry, wastewater treatment, ecotechnology and toxicology. This interdisciplinary approach will improve overall interpretation of the findings, which should meet with broad approval from the scientific community. We combine the knowledge of eight research groups: JSI (O2 and B2), University of Ljubljana (FCE and FME), NIB, GSS, IEI and IPS and several end-of-pipe users: IEI, 3 WWTP, Snaga, 2 hospitals NIHP. In addition renowned international research groups CSIC, EAWAG and MU are supportive of this research. An interdisciplinary approach will bring together research institutes and end-of-pipe users to propose actual solutions. Due to its interdisciplinary nature and the excellence of the involved researchers, we expect to publish in popular science and high impact factor journals, apply for patents, and transfer knowledge to industrial partners and postgraduate students.
Significance for the country
The proposed research is highly relevant to society from the point of view of protecting valuable water resources. It will show the extent of pollution in the Slovene environment by priority pharmaceuticals using conventional and passive sampling techniques. The study will determine the efficiency of different (conventional and advanced) WWTP processes towards removing potentially harmful emerging contaminant residues and propose alternative treatment technologies to be coupled to the most common WW treatment technology. The in-depth knowledge on the behaviour and fate of priority pharmaceutical residues will enhance societal awareness about improper disposal of pharmaceuticals and this knowledge can be transferred to end-users and students within the International Postgraduate School Jožef Stefan, where the study of cutting edge ecotechnology is an important module. In economic terms we envisage that it will lead to more efficient and cost effective WW treatment. In addition, we expect that the research will have industrial applicability leading to patents applications. Importantly, it will be available to support the actions needed when European legislation, namely the WFD, transfers these priority list pollutants to regularly monitored substances. The results will also be applicable to other pharmaceuticals and new emerging contaminants to be monitored under the WFD (BPA and its alternatives).
The proposed research impacts include the following:
1. Improved water treatment and environmental quality
Degradation of natural water resources through pollution is a major concern and ecosystem wellbeing relates directly to human health and must be factored in to any assessment of socio-economic impacts. Just as relevant are the impacts/stress on fauna and flora in sensitive areas. Maintaining the integrity of ecosystems is of fundamental importance.
2. Impact on European legislation
Outcomes can impact European legislation, namely WFD regarding setting discharge limits of pharmaceutical and organic pollutant residues from different sources. They will also be an important factor in determining the priorities for investments in pollution mitigation projects. The costs of mitigation can be considerable and prevention is a cheaper option, but depends on identifying the principle pathway, by which pollutants enter the environment. Additionally, knowledge on the fate of pharmaceutical residues will enhance social awareness concerning improper disposal of pharmaceuticals, and other waste potentially containing toxic compounds (e.g. bisphenols).
3. Potential applicability in different industrial branches
Studied pharmaceuticals may be considered as model compounds, i.e. as representatives of structurally different pharmaceuticals and other trace persistent organic pollutants. In this sense, the proposed treatment technologies are applicable to other industrial branches dealing with elimination of other organic pollutants (e.g. BPA and its alternatives) and their discharges.
Most important scientific results
Interim report,
final report
Most important socioeconomically and culturally relevant results
Interim report,
final report
