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What’s Lurking in Europe’s Freshwater?

  By Kt Miller, ASC Microplastics Adventurer As Mose drove, I could see a large stream running along the side of the road on the way to the airport in Ljubljana, the capital of Slovenia. “When you see a good spot, can we pull over and get another water sample from that stream?” I asked. “Yeah,...

KT's sampling data for ASC Microplastics. (Photo by KT Miller)
Cowgirl boots and KT’s sampling data for ASC Microplastics (Photo by KT Miller)


By Kt Miller, ASC Microplastics Adventurer

As Mose drove, I could see a large stream running along the side of the road on the way to the airport in Ljubljana, the capital of Slovenia.

“When you see a good spot, can we pull over and get another water sample from that stream?” I asked.

“Yeah, but I know a better place,” Mose said with a half smile. He turned off the highway and zipped through a maze of narrow streets in a small village.

I had spent the previous two weeks skiing in Slovenia and Italy with my friends Brigid Mander, Molly Baker, and Liza Sarychevski. We met Mose, also a skier, along the way. When Adventurers and Scientists for Conservation told me about its new freshwater microplastics project—which mobilizes outdoor adventurers to help collect water samples for testing—I was thrilled to collect some of the project’s first samples during our trip.

We passed quickly through the town and into the mountains. Gravity pulled me side to side in a sway as Mose drove up and up a winding forest road. Europeans like to drive fast.

The road became bumpy, and Mose dodged potholes and a fallen tree. After about ten minutes, we came to a stop. It was pouring rain. I mean really pouring.

Mose pointed out the passenger’s window on the right. A perfect waterfall cascaded down from the mountains 60 feet above us.

Collecting samples at the base of a waterfall—in the rain—meant getting drenched.  (Photo courtesy KT Miller)

“How about this spot?” he asked, grinning again. “People say that this is the most beautiful waterfall in Slovenia.”

We hopped out of the van and began a short, steep climb to the base of the waterfall, me in cowgirl boots, Mose in Birkenstocks. As we approached the cascading stream, it dawned on me that someone would have to get soaked to catch falling water from or even near the cascade, but on second thought, we were already soaked.

I cautiously approached the pool at the base of the waterfall. Wet rocks and cowgirl boots are a dangerous combination. I went through the motions: Rinse three times, fill, foil, lid, GPS coordinates, done.

When we turned back toward the car, I saw an old shoe sole on the ground.

“Are you missing your ‘soul’?” Mose asked, joking.

I picked it up to bring to the city and recycle. I thought to myself, That’s how we end up with plastic everywhere, even in high mountain streams and rural rivers.

We laughed at the comical scene as we scurried back down the trail in the rain, getting completely soaked, all to put some water in a bottle and ship it away.

As we slid back into the van, Mose looked at me and said with complete sincerity, “I hope there’s no plastic here.”

To be honest, I was with a team collecting samples in Greenland last year, and I wasn’t the one keeping track of everything and doing the sampling, so I didn’t think about it that much. But as the person looking for spots to sample and writing down all the information myself, I thought about the issue a lot more.

I found myself wondering, How much plastic will be here? and thinking strategically about where I was choosing to take samples. I was curious to know if the samples from the mountains would have fewer microplastics than the samples from the cities and lakes. I hoped it would be so. The remote places in Europe see a fair amount of human traffic, so I expected the water would have more plastic than where I live in Montana, or Alaska, or somewhere else really remote. I wondered and hoped that I might be pleasantly surprised and there would be almost no plastic in the water at all. Time would tell.

Mose and I met up with Brigid in Ljubljana, the capital of Slovenia, and went to explore the city center and find a place to have dinner. I carried another sampling bottle with me, feeling like a total nerd.

“Is this ridiculous?” I asked Mose and Brigid. “I really want to get a sample from the river.”

There is a river that runs through a man-made canal in the middle of the city center. Historic bridges—built as early as the 1300s—span the canal, each with a name and ornate architectural decor. One of them even has dragons.

We walked across the first bridge, and I looked down. It would be impossible to get to the water. The canal walls were almost vertical, covered in slime, with a meter drop from the top of the concrete to the water. I didn’t have any string to lower the bottle off of a bridge. The odds seemed slim of collecting a sample there. We found a place to eat dinner.

"People say this is the most beautiful waterfall in Slovenia." (Photo by KT Miller)
“People say this is the most beautiful waterfall in Slovenia.” (Photo by KT Miller)

After dinner, we ventured back out in the still pouring rain, water falling and dancing in the glow of the street lights. I spotted a ladder and then a set of stairs going down toward the river.

Maybe I could jump the fence, I thought as we approached. I tried the handle on a wrought iron gate and, to my surprise, it was open! I couldn’t believe my luck. I scampered down to the water and went through the motions again: Rinse three times, fill, foil, lid, GPS, done. Feeling content, we walked back to our hotel in the pouring rain and prepared to depart Slovenia the next day.

I was curious to see the results of all of the samples we took in Slovenia and Italy, but I was especially curious to compare the water samples from the waterfall and from the river in downtown Ljubljana.

“Do you think that the waterfall we took a sample from flows into this river?” I asked Mose as he got back into his van to return home.

“Oh yes,” he replied “definitely.”

And with that, Brigid and I said goodbye to our Italian friend, and our Slovenian adventure came to a close.

That’s one of the crazy things about life: It always continues on—moments are fleeting and time is constantly moving forward, flowing, just like the rivers do. Each time we choose a fork in the river or a fork in the road, it affects where we end up, determining the path of our future. In that same way, everything we put into our water will eventually affect what is downstream. We must choose to take care of our water in the same way we choose to take care of our future, aware of what may be many generations downstream.

It turns out that all of our samples had two pieces of microplastic, except the first sample, which had five. That means the waterfall in the mountains had the same amount of microplastic as the river downstream in downtown Ljubljana. The sample that had five pieces of plastic came from a lake in the middle of a small town, with a trail around it and hotels and restaurants operating along its shore.

Unfortunately, Mose’s hope was not true, and there were indeed microplastics in the freshwater of his mountainous home. It saddens me to share this news with him, but it is a good reminder of the far-reaching impact of humanity and the consequences of our choices as consumers and citizens of the world.

So I dare you to try to decrease your impact and the impact of those around you, and to ask yourself, What did I buy wrapped in plastic today?

Learn more about ASC on our website, the Field Notes blog, and by following us on FacebookTwitterInstagram, and Google+

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Meet the Author

Author Photo Gregg Treinish
Gregg Treinish founded Adventure Scientists in 2011 with a strong passion for both scientific discovery and exploration. National Geographic named Gregg Adventurer of the Year in 2008 when he and a friend completed a 7,800-mile trek along the spine of the Andes Mountain Range. He was included on the Christian Science Monitor's 30 under 30 list in 2012, and the following year became a National Geographic Emerging Explorer for his work with Adventure Scientists. In 2013, he was named a Backpacker Magazine "hero", in 2015, a Draper Richards Kaplan Entrepreneur and one of Men's Journal's "50 Most Adventurous Men." In 2017, he was named an Ashoka Fellow and in 2018 one of the Grist 50 "Fixers." Gregg holds a biology degree from Montana State University and a sociology degree from CU-Boulder. He thru-hiked the Appalachian Trail in 2004. Read more updates from Gregg and others on the Adventure Scientists team at Follow Adventure Scientists on Instagram @adventurescientists, on Facebook @adventurescientists, and on Twitter @AdvScientists.