Drugs in wastewater – a Polish biopreparation for their removal and Bio-Sponge

Drugs in wastewater is a challenge that treatment plants will soon face. The European Commission plans to tighten regulations in this regard. However, this is a problem not only for the treatment plant. We need to realize that our body cannot completely metabolize ibuprofen or ketoprofen, which belong to the so-called “ibuprofen”. Non-steroidal anti-inflammatory drugs (NSAIDs), sold without a prescription. Excreted from our bodies, they go to the sewage treatment plant, from there to the river, and from the river to the tap. They harm not only us, but entire ecosystems.

Studies confirm the presence of more than 80 types of pharmaceuticals in water. Hence the urgent need to remove them from wastewater, and thus from the environment. Scientists are discovering more and more ways to eliminate them, and some are already being implemented at treatment plants. The basis of the optimal method should be efficiency, availability, and low implementation and operating costs. This is the solution proposed by a team of researchers from the University of Silesia in Katowice. I discuss the project with Dr. Anna Dzionek of the Department of Natural Sciences.

Agnieszka Hobot: The title of the project sounds mysterious: A formulation that stimulates the degradation of non-steroidal anti-inflammatory drugs based on bacterial strains immobilized on a natural carrier. I would like to ask you to tell our readers about the project’s objectives and expected results.

Anna Dzionek: In a nutshell, the whole project involves the development of a biopreparation, that is, a preparation that contains live microbial cells. In our case, these are bacteria isolated from the environment that are capable of degrading non-steroidal anti-inflammatory drugs, that is, for example, ibuprofen, naproxen or paracetamol. These are substances that we all have in our medicine cabinets. Most of them are available without a prescription. Our body is unable to metabolize them, so they end up in the wastewater treatment plant. With that said, there is no way to degrade them there either.

There are no microorganisms in biological systems that can remove NSAID residues, so we are developing a way to introduce them. It involves the delivery of specialized microorganisms to the treatment plant on a natural medium. Introduced directly, they would not have survived there for long. We want to introduce microorganisms into the treatment plant on a special natural sponge. We assume that they will catch these non-steroidal anti-inflammatory drugs at the wastewater treatment stage so that they do not enter the environment and have no negative impact on aquatic organisms and humans. Drugs are already detected in drinking water, from where they enter our bodies.

AH: Won’t the introduction of Bio Sponges disrupt the operation of activated sludge at the treatment plant?

AD: Well, that is the biggest conundrum of any formulation. This is difficult to assess before entering the main chambers of the treatment plant. We conducted laboratory tests. We tested how activated sludge would work with our formulations on a scale of up to 5 liters of wastewater. We hope to test our product on a larger scale next year, such as in a 200-liter separate line at a wastewater treatment plant. If these tests show no abnormalities, then in the next step we will already move on to treating all the wastewater flowing into the treatment plant.

AH: Should treatment plants prepare for the high cost of such implementation?

AD: If we pass all the tests and there are no contraindications to introducing our sponges into the main chambers of the treatment plant, this technology will be ultra-low-cost, very fast and environmentally friendly. If, on the other hand, there are any problems, even if only with the interaction with the equipment used at the treatment plant, we will try to minimize the cost of connecting a separate line. This would mean another stage of treatment after mechanical-biological.

AH: What is such a Bio Sponge and how does it effectively remove drugs from wastewater?

AD: It’s a simple Luffa (Loofah) plant sponge that you can buy in organic stores – usually used for body wash. It is properly prepared by us, including. Cut into 2x1x1 cm pieces. It is on it that we immobilize (immobilize) the bacterial strains. Under laboratory conditions, we are guaranteed the highest drug degradation efficiency for the first month. After that, it drops by about 20%.

In the testing environment, the sponge structure persists for 3 months. We do not want the media to linger in the treatment plant chambers. They are only to introduce the microorganisms and ensure their greater survival rate during the initial phase of purification. For a month the product works great, then the sponge starts to break down and the performance minimally decreases. Nevertheless, after 3 months, we continue to observe drug degradation, so this is an indirect sign that the microorganisms have also passed into activated sludge. The important thing is that we test the effectiveness of our method based on the distribution of environmental concentrations, not the maximum concentrations they can reach.

AH: What drugs in wastewater are subject to degradation and into what substances?

AD: At this point, we are able to guarantee the distribution of paracetamol, which is not exactly a non-steroidal anti-inflammatory drug, but also has antipyretic effects, ibuprofen, naproxen and diclofenac. Apap, ibuprofen and naproxen break down to carbon dioxide and water, while with diclofenac we observe transformation to hydroxylated derivatives.

These drugs actually break down into substances that are harmless to the aquatic environment.

We observe their degradation within 24 hours (except for naproxen and diclofenac, because as bicyclic compounds they are very difficult to degrade and need more time).

AH: Have the first takers for the implementation of Bio Sponges technology already appeared?

AD: They are the first ones interested in such wastewater treatment. Questions arise as to whether we can come up with a solution that could be tested on separate process lines. Water and sewage companies are interested in formulations that will be able to treat wastewater of various types of substances, because the problem is not only non-steroidal anti-inflammatory drugs, but also beta-blockers, antibiotics and hormones. There is really a whole range of it. There are plans to make it mandatory for treatment plants to monitor more than a dozen new substances, drug residues precisely. It will therefore be necessary to comply with the relevant parameters of treated wastewater.

AH: How long have you been conducting research and what are the plans for the future?

AD: The project itself has been going on since the beginning of last year, but we have been dealing with non-steroidal anti-inflammatory drugs and their distribution for 10 years. We want to close the work this year. The laboratory stages have already been completed. We are currently compiling the results and preparing materials for publication. We also plan to patent the results of our research. Some of them have already been reported to the office.

The project’s research team from the Faculty of Natural Sciences at the University of Silesia consists of Anna Dzionek, PhD, Agnieszka Nowak, PhD. Danuta Wojcieszyńska, prof. UŚ, and Ph. Ursula Guzik, prof. UŚ. The project is funded by NCBiR.