The ‘Swimming Professor' takes sustainability lessons from the Danube

To bring attention to water pollution, Andreas Fath, a chemistry professor at Furtwangen University, literally wades into the subject matter.

The so-called "swimming professor" most recently swam the Danube River, which send 4 tons of microplastic (0.1 mm to 5 mm) into the Black Sea every day, according to research from the University of Vienna.

Fath traversed the 1,678-mile (2700 km) swimmable section of Europe's longest river, which flows through 10 countries to the Black Sea.

Following along on the land, a mobile workshop gave out informational materials to the public attending related events, such as cleanups, swim meets, paddling activities, lectures and receptions.

Also on the trek, a mobile laboratory analyzed water samples from a passive sampler attached to Fath's wetsuit to imitate fish skin and provide additional insights, including a look at tire additives.

The aim was to raise awareness about water pollution and the dangers of microplastics as well as to enhance appreciation of the Danube as a natural habitat vital to the people living along the river.

Furtwangen University, a co-organizer of the project, provided the mobile laboratory, public relations work and doctoral students.

The project was financially supported by Arburg, the Baden-Württemberg Foundation, Postcode Lottery, Hansgrohe and Menschen brauchen Menschen e.V.

Fath told Plastics News about his efforts in a phone interview ahead of a speaking engagement during K2022 at the Arburg booth.

Q: The rivers in Asia get a lot of attention for being dumping grounds that contribute to ocean trash gyres. Were people you met on the shores of the Danube River surprised to find out it washes 4 tons of microplastic into the Black Sea every day? What is the source of this estimate?

Fath: This is 4.2 tons of microplastic each day that runs down the Danube and enters the Black Sea. There's more tons of other plastic. This was measured by the University of Vienna in 2014. Our research work now attempts to verify this number, which we assume has risen because more plastic is being produced and we haven't made a big step in terms of recycling it in recent years. There's a correlation between plastic production and plastic litter in nature. We expect it's now more than 4.2 tons of microplastics each day. This is a shocking number to people and we get into discussions about where does this come from, what can we do to avoid this, how do we improve the situation and its impacts to nature and our health.

Q: Microplastics can be ingested by fish that people may eat. Don't humans release microplastics because our bodies can't break them down? What threats does this pose?

Fath: People release microplastics. Vienna University researchers investigated peoples' excrement and they found microplastic. But, be aware. If nature is not capable to decompose plastics products — nature needs 500 to 1000 years — one digestion step in a body can't digest plastic. And the problem with plastic is the additives — softeners, UV stabilizers, flame retardants, pigments and other additional chemicals — can be extracted from the body. Like hot water extracts coffee from coffee beans, POPs (persistent organic pollutants) can be released into our food chain.

Q: What are some of the impacts to nature and our health?

Fath: We have research workshops and interactive equipment where young people can understand how microplastic came to be. We also present the adhesion properties of microplastic and the magnetic effect it has. It adheres to POPs (persistent organic pollutants) in the water.

Fish and sheels then eat and filter the microplastics and pollutants, putting seafood in danger.

Seventeen percent of the world's population gets its food from the sea and in some places its almost 100 percent.

Other research work at the Tennessee aquarium investigated fish guts. It shows fish eat microplastics and ingestion of toxic material is higher than without microplastic influence.

Of course the fish release the microplastic and we don't eat the fish guts, but during metabolism the fish's absorbed material is desorbed and stays in the fish tissue. So microplastic works like a trojan horse to introduce other pollutants in our food chain.

Q: You have likened rivers to plastic mills. How is that?

Fath: Rivers crush stones from the Alps to fine sands at the shores of the Black Sea. The same thing happens to the plastic litter that enters the water. I can hear the noise of the water. The stones crushing under the sediment. More than 90 percent of plastic products are heavier than water. They go down into the mill where the stones crush down the plastic products into microplastic.

You can hear this mill working and see under the microscope. We have small plastic bottles and we fill them with stones from the river. The students shake the plastic bottles and take the water sample, look at it under the microscope and they can see the microplastics. It's an interactive way to demonstrate: Hey, that's a crime when you place your plastic bottle in nature somewhere because with climate change we have high rainfalls sometimes and then everything is washed into the rivers and then the mill starts to work, crushing down the plastic products into microplastics.

Q: What made some sections of the Danube unswimmable for you?

Fath: It was low water at the beginning and dams of course. We'd carry a paddle boat around the dam and then I'd jump in again. And then I skipped Belgrade after a biologist raised concerns. Some 1.7 million people deliver their waste water and excrements with e coli into that river. I didn't want to risk infection. I wanted to reach the Black Sea so I skipped that. Then, the story changed about why I didn't swim through Belgrade. Is it dangerous? Can we eat the fish from there? How long can you be in the water? Can we use it for leisure? It was good choice not to swim there. It brought attention to the NGOs fighting for sewage treatment plants to take care of their water.

Q: What kind of plastic did you encounter mostly and partly while swimming the Danube River?

Fath: I saw everything but mostly bottles and styrene packaging — a lot of packaging. In the water you don't see so much floating because most of the plastic is heavier than water and it goes down. Every place where I left the water I found packaging material in all 10 countries.

Q: How about the passive sampler attached to the wetsuit to imitate fish skin? Did you wear it for all three river swims? Has it provided any additional insights?

Fath: This is a membrane you can buy that is often placed on bridges and at tributaries to extract what's on surface to investigate discharges and determine the guilty party. I took it on all swims and every changed it to analyze developments. For example, at the beginning of the Rhine we found 30 substances and at the end we found 128 substances.

At the Danube we had a different protocol. We worked with researchers from the University of Vienna and they wanted to look at additives to tires. Tire friction has the highest impact of microplastics released into our nature. The rubber itself is not problem but the additives to tires like polyaromatic rings or softeners. The wind carries them to the water.

We have an education model where there's a wheel on plate. People can turn the handle of the wheel and on the other side there's a filter and you can see the particles on the filter and look at them under a microscope. We make all this visible. We not only tell people about it. We make it visible. Knowledge stays when combine with emotions so we do the interactive models.

Q: In addition to the volume of plastic in waterways, you're sounding the alarm about the surfaces of microplastics possibly being coated with pesticides, pharmaceuticals, antibiotics, and hormones. And, that has raised other questions for you and your students, which has turned into a new project. What else are your students working on?

Fath: I gave two of my students a job. If microplastic is capable to adsorb all these pollutants, why don't we use microplastics as a filter material? A start-up company called Polymer Active is using plastic litter to make microplastic and microplastic powder as a filter material to clean water. This has the same effect as active carbon used to clean water. This company is called Polymer Active — a very smart name because the polymer can still be active. The polymer can still be something positive if you use it in the right way.

This has three advantages. First of all it give plastic litter a new lifetime, which saves our surroundings. Then, it cleans water, which saves water. And then, at end of the day, you don't have to combust it like you have to do with active carbon so then you reduce carbon dioxide formation.

This is a timely issue. At our sewage treatment plant here in Biberach (Kinzigtal), we're working on the installation of a fourth treatment step at the municipal waste water treatment plant. The fourth step is based on active carbon, which adsorbs trace compounds released into our rivers but is a high-cost technology. You have to prepare active carbon, which costs high energy from out of biomass and at the end of the day you have to combust it.

If you take plastic, which we have enough for free, because people throw it everywhere, this is a good concept to increase recycling.

I always end my talks with this positive view because other facts I tell from river expeditions are very negative and people are very depressed at the end of the talks. So I give this view into the future of what we can do. It's one point of how we can tell people that plastic litter is not useless. We can do something with it.

Q: What are your days like during one of these river swims? How many hours are you in the water? How do you keep going physically and mentally?

Fath: I'm in the water 8-10 hours a day. In April when the water was 11 degrees centigrade that was pretty cold. I thought the snow melt of the alps would help for a better current of the river but because of climate change we did the wrong calculation. To keep our daily schedule, I had to swim 8-10 hours to reach the next workshop, city or parking place for the boat. We had no flexibility in our time.

I was a swimmer in a professional way in my first life and I kept in shape. The swimming at the beginning is hard but the challenge helps you get better. It's a training effect. After 2-3 weeks of swimming every day for 8 hours, your body adapts to the job. I came out after 8 weeks in the best shape of my life.

I know how to swim long distances. It's easier than walking because the water carries you. It doesn't hurt your bones and knees everything.

I come by this by two passions: swimming and water protection and chemistry. Its sports meets science and now we add education. Scientists will read papers on these topics but plastic pollution of our water streams and Earth are societal problems so you have to reach society.

Q: What action at the least do you hope the public and industry are moved to?

Fath: In the words of Jack Johnson, who wrote a song about three Rs, I'd say reduce, reuse and recycle. Plastic isn't a bad material if it stays in the loop of use.

Look at hospitals and cars. Plastic has its benefits for our health and safety. But with packaging, when it is released into water streams, the boomerang comes back and our health is in danger.

I hope people think about what they're doing. That they reduce plastic where they can or reuse it as often as possible and for the industry to produce products that can be recycled easily. If a product has three or different plastic types, nobody is separating them because it costs money. Nobody is doing it because we are economically driven.

The message to the industry is make products that can be recycled or that are biodegradable. That's a part of the industry starting with low volume but I hope it rises in the next years and leads to production of biodegradable plastic products.

To bring attention to water pollution, Andreas Fath, a chemistry professor at Furtwangen University, literally wades into the subject matter.

The so-called "swimming professor" most recently swam the Danube River, which sends 4 tons of microplastic (0.1-5 mm) into the Black Sea every day, according to research from the University of Vienna.

Fath traversed the 1,678-mile (2700-kilometer) swimmable section of Europe's longest river, which flows through 10 countries to the Black Sea.

Following along on the land, a mobile workshop gave out informational materials to the public attending related events, such as cleanups, swim meets, paddling activities, lectures and receptions. Also on the trek, a mobile laboratory analyzed water samples from a passive sampler attached to Fath's wetsuit to imitate fish skin and provide additional insights, including a look at tire additives.

The aim was to raise awareness about water pollution and the dangers of microplastics as well as enhance appreciation of the Danube as a natural habitat vital to the people living along the river. Furtwangen University, a co-organizer of the project, provided the mobile laboratory, public relations work and doctoral students.

The project was financially supported by Arburg, the Baden-Württemberg Foundation, Postcode Lottery, Hansgrohe and Menschen brauchen Menschen e.V.

Fath told Plastics News about his efforts in a phone interview ahead of a speaking engagement during K 2022 at the Arburg booth.

Q: The rivers in Asia get a lot of attention for being dumping grounds that contribute to ocean trash gyres. Were people you met on the shores of the Danube River surprised to find out it washes 4 tons of microplastic into the Black Sea every day? What is the source of this estimate?

Fath: This is 4.2 tons of microplastic each day that runs down the Danube and enters the Black Sea. There's more tons of other plastic. This was measured by the University of Vienna in 2014. Our research work now attempts to verify this number, which we assume has risen because more plastic is being produced and we haven't made a big step in terms of recycling it in recent years. There's a correlation between plastic production and plastic litter in nature. We expect it's now more than 4.2 tons of microplastics each day. This is a shocking number to people and we get into discussions about where does this come from, what can we do to avoid this, how do we improve the situation and its impacts to nature and our health.

Q: Microplastics can be ingested by fish that people may eat. Don't humans release microplastics because our bodies can't break them down? What threats does this pose?

Fath: People release microplastics. Vienna University researchers investigated peoples' excrement and they found microplastic. But, be aware. If nature is not capable to decompose plastics products — nature needs 500 to 1,000 years — one digestion step in a body can't digest plastic. And the problem with plastic is the additives — softeners, UV stabilizers, flame retardants, pigments and other additional chemicals — can be extracted from the body. Like hot water extracts coffee from coffee beans, POPs (persistent organic pollutants) can be released into our food chain.

Q: What are some of the impacts to nature and our health?

Fath: We have research workshops and interactive equipment where young people can understand how microplastic came to be. We also present the adhesion properties of microplastic and the magnetic effect it has. It adheres to POPs in the water.

Fish and shells then eat and filter the microplastics and pollutants, putting seafood in danger. Seventeen percent of the world's population gets its food from the sea and in some places it's almost 100 percent.

Other research work at the Tennessee aquarium investigated fish guts. It shows fish eat microplastics, and ingestion of toxic material is higher than without microplastic influence.

Of course the fish release the microplastic and we don't eat the fish guts, but during metabolism the fish's absorbed material is desorbed and stays in the fish tissue. So microplastic works like a trojan horse to introduce other pollutants in our food chain.

Q: You have likened rivers to plastic mills. How is that?

Fath: Rivers crush stones from the Alps to fine sands at the shores of the Black Sea. The same thing happens to the plastic litter that enters the water. I can hear the noise of the water. The stones crushing under the sediment. More than 90 percent of plastic products are heavier than water. They go down into the mill, where the stones crush down the plastic products into microplastic.

You can hear this mill working and see under the microscope. We have small plastic bottles and we fill them with stones from the river. The students shake the plastic bottles and take the water sample, look at it under the microscope and they can see the microplastics. It's an interactive way to demonstrate: "Hey, that's a crime when you place your plastic bottle in nature somewhere because with climate change we have high rainfalls sometimes and then everything is washed into the rivers and then the mill starts to work, crushing down the plastic products into microplastics."

Q: What made some sections of the Danube unswimmable for you?

Fath: It was low water at the beginning and dams of course. We'd carry a paddle boat around the dam and then I'd jump in again. And then I skipped Belgrade after a biologist raised concerns. Some 1.7 million people deliver their waste water and excrements with E.coli into that river. I didn't want to risk infection. I wanted to reach the Black Sea so I skipped that. Then, the story changed about why I didn't swim through Belgrade. Is it dangerous? Can we eat the fish from there? How long can you be in the water? Can we use it for leisure? It was good choice not to swim there. It brought attention to the NGOs fighting for sewage treatment plants to take care of their water.

Q: What kind of plastic did you encounter mostly and partly while swimming the Danube River?

Fath: I saw everything, but mostly bottles and styrene packaging — a lot of packaging. In the water you don't see so much floating because most of the plastic is heavier than water and it goes down. Every place where I left the water I found packaging material in all 10 countries.

Q: How about the passive sampler attached to the wetsuit to imitate fish skin? Did you wear it for all three river swims? Has it provided any additional insights?

Fath: This is a membrane you can buy that is often placed on bridges and at tributaries to extract what's on the surface to investigate discharges and determine the guilty party. I took it on all swims and changed it to analyze developments. For example, at the beginning of the Rhine we found 30 substances and at the end we found 128 substances.

At the Danube we had a different protocol. We worked with researchers from the University of Vienna and they wanted to look at additives to tires. Tire friction has the highest impact of microplastics released into our nature. The rubber itself is not the problem but the additives to tires like polyaromatic rings or softeners. The wind carries them to the water.

We have an education model where there's a wheel on plate. People can turn the handle of the wheel and on the other side there's a filter and you can see the particles on the filter and look at them under a microscope. We make all this visible. We not only tell people about it; we make it visible. Knowledge stays when combined with emotions so we do the interactive models.

Q: In addition to the volume of plastic in waterways, you're sounding the alarm about the surfaces of microplastics possibly being coated with pesticides, pharmaceuticals, antibiotics and hormones. And that has raised other questions for you and your students, which has turned into a new project. What else are your students working on?

Fath: I gave two of my students a job. If microplastic is capable to adsorb all these pollutants, why don't we use microplastics as a filter material? A startup company called Polymer Active is using plastic litter to make microplastic and microplastic powder as a filter material to clean water. This has the same effect as active carbon used to clean water. This company is called Polymer Active — a very smart name because the polymer can still be active. The polymer can still be something positive if you use it in the right way.

This has three advantages. First of all, it give plastic litter a new lifetime, which saves our surroundings. Then, it cleans water, which saves water. And then, at end of the day, you don't have to combust it like you have to do with active carbon so then you reduce carbon dioxide formation.

This is a timely issue. At our sewage treatment plant here in Biberach (Kinzigtal), we're working on the installation of a fourth treatment step at the municipal wastewater treatment plant. The fourth step is based on active carbon, which adsorbs trace compounds released into our rivers but is a high-cost technology. You have to prepare active carbon, which costs high energy from out of biomass and at the end of the day you have to combust it.

If you take plastic, which we have enough for free, because people throw it everywhere, this is a good concept to increase recycling.

I always end my talks with this positive view because other facts I tell from river expeditions are very negative and people are very depressed at the end of the talks. So I give this view into the future of what we can do. It's one point of how we can tell people that plastic litter is not useless. We can do something with it.

Q: What are your days like during one of these river swims? How many hours are you in the water? How do you keep going physically and mentally?

Fath: I'm in the water eight to 10 hours a day. In April, when the water was 11 degrees centigrade, that was pretty cold. I thought the snow melt of the alps would help for a better current of the river but because of climate change we did the wrong calculation. To keep our daily schedule, I had to swim eight to 10 hours to reach the next workshop, city or parking place for the boat. We had no flexibility in our time.

I was a swimmer in a professional way in my first life, and I kept in shape. The swimming at the beginning is hard, but the challenge helps you get better. It's a training effect. After two three weeks of swimming every day for eight hours, your body adapts to the job. I came out after eight weeks in the best shape of my life.

I know how to swim long distances. It's easier than walking because the water carries you. It doesn't hurt your bones and knees everything.

I come by this by two passions: swimming and water protection and chemistry. Its sports meets science, and now we add education. Scientists will read papers on these topics but plastic pollution of our water streams and Earth are societal problems so you have to reach society.

Q: What action at the least do you hope the public and industry are moved to?

Fath: In the words of Jack Johnson, who wrote a song about three Rs, I'd say reduce, reuse and recycle. Plastic isn't a bad material if it stays in the loop of use.

Look at hospitals and cars. Plastic has its benefits for our health and safety. But with packaging, when it is released into water streams, the boomerang comes back and our health is in danger.

I hope people think about what they're doing, that they reduce plastic where they can or reuse it as often as possible and for the industry to produce products that can be recycled easily. If a product has three or different plastic types, nobody is separating them because it costs money. Nobody is doing it because we are economically driven.

The message to the industry is make products that can be recycled or that are biodegradable. That's a part of the industry starting with low volume, but I hope it rises in the next years and leads to production of biodegradable plastic products.