Using moss to test for urban pollution, NCAA concussion protocol fails, and one of the blackest substances ever made

Mossy lead-detector

With the environmental clean-ups of the last several decades, the amount of toxic lead we’re exposed to on a daily basis has dropped significantly. But lead is still present in the environment: in old paint, in soil, and as it turns out, strung on utility poles overhead. Up until the 1950s, it was common practice to sheath telephone cables in lead to protect them from the elements. Some of these cables are still around in older parts of U.S. cities, including Portland. And new research suggests they are slowly releasing the harmful metal (which is particularly harmful to children) into the surrounding environment.

Scientists at Oregon State University are analyzing lead levels in Portland neighborhoods using an air monitoring system that’s found in nature: tree moss. The plant collects all of its nutrients from the atmosphere and, in the process, absorbs pollutants. And because moss is pretty much everywhere, it’s relatively easy to test samples from hundreds of locations to track down sources of pollution. A previous study by the U.S. Forest Service managed to trace high cadmium concentrations in urban moss to two stained-glass manufacturers in Portland.

This time, the OSU researchers found that lead levels in the moss samples from neighborhoods with lead-sheathed cables were more than two times higher than the samples from neighborhoods without them. They also concluded that the lead can move around in the environment, likely when the contaminated soil underneath the cables gets picked up by the wind.

The team has set up a website with a guide for identifying lead-sheathed cables and advice for anyone who lives near these cables.

Dos and Don’ts

Do

• Consider getting your family tested for lead, especially if you have young children. Talk to your healthcare provider to learn more.
• Get your soil tested for lead. Find out more in this Healthy Soils publication from the Oregon Health Authority. Accredited labs that provide testing for lead in soil can be found here.
• If the soil in the area of concern is bare, consider laying down some groundcover such as mulch, bark or gravel. Avoid vegetative groundcover that would require digging in the soil. If the area is large, you may want to test the soil for lead contamination first, to see if the groundcover is even necessary.

Do not

• Garden under the cables or in soils within a few feet of the cables.
• Allow children to play on these soils.
• Disturb the soil, thereby mobilizing dust that could be inhaled.
• Carry potentially lead-contaminated soil into your home on shoes.

Source: Oregon State University

The study was published in the journal Communications Earth & Environment here.

Concussion protocol fails

College football season is nigh — bringing with it (old-school) endzone spikes and spikes in the number of athletes in the so-called “concussion protocol,” which keeps them out of games for health reasons. Concussions are brain injuries that vary in severity, but the worst of them (and repeated concussions) can lead to long-term problems. Concussions happen in football more than any other NCAA sport, except wrestling.

Now researchers at the University of Washington are calling into question the effectiveness of part of the protocol designed to diagnose concussions. Team medical staff look at three factors to figure this out: symptoms, balance and cognitive skills. It’s the screening of cognitive skills, which in part relies on word-recall, that’s falling short.

The team looked at 92 athletes that were diagnosed with concussions and found that nearly half of them performed normally on the word-recall test. The researchers say the results show this part of the protocol isn’t actually that useful in predicting concussion.

Instead, they found that the best predictor was athletes’ answers to questions about their symptoms. Yet this also poses a problem. Athletes can be less than forthcoming about symptoms when they know revealing them means their playing day would be over.

The paper in JAMA Network Open can be read here.

When camas became a crop (sort of)

Come across a Pacific Northwest prairie or mountain meadow in mid-spring, and you may have witnessed a sea of spire-like purplish-blue flowers. There’s a good chance that’s camas, which springs from an onion-potato tasting bulb that was once abundant in the region and a staple of many Native American diets.

Physical evidence of Indigenous use of the bulb as a food source goes back at least 8000 years. But anthropologists at Oregon State University and the University of Oregon examined camas bulbs found at 11 archeological sites in the Willamette Valley and found evidence that a significant shift happened a few thousand years later.

On bulbs recovered from early archeological sites, the researchers found a wide variety of bulb ages — some harvested young and smaller, others older and larger. But beginning about 3500 years ago, the mix changed: the bulbs found were mostly older, indicating that the harvests became far more targeted. The researchers suggest this is when early Americans transitioned from opportunistic gathering of camas to more active stewardship to ensure future abundance.

This timing roughly coincides with a shift towards a more stable climate and evidence of increased low-magnitude fires on the landscape, which scientists believe were intentionally set to create and maintain habitat for useful plants and animals.

The study suggests there could have been other harvest strategy shifts far earlier as well, but there’s not enough data to draw solid conclusions.

Read the paper published in The Holocene here.

Wood is the new super-black

Ever wonder what it’s like to look into the void? Scientists worldwide have been working for decades to create “super-black” materials that absorb nearly all visible light. These substances are sought after in fields like astronomy, where non-reflective surfaces inside telescopes can help reduce stray light and make their images clearer.

Researchers at the University of British Columbia have stumbled upon a new way to achieve super-black using an abundant resource: wood. While attempting to make wood water-repellent with high-energy plasma, the scientists were surprised to find that the surfaces they treated turned extremely black. They named this material Nxylon, a mashup of Nyx, the Greek goddess of the night, and xylon, the Greek word for wood.

The material reflects less than one percent of visible light, which ranks it among the least reflective substances ever made. The inventors hope to find industrial applications for their accidental discovery, but for now they know Nxylon could replace endangered naturally dark woods such as ebony and rosewood in art, furniture, and jewelry.

Read more details in the journal Advanced Sustainable Systems here.

Social media is … boring?

Back-to-school time is here in the Pacific Northwest, and one of the biggest issues facing schools and districts this year is how to regulate cell phone use by students. Phones in schools are widely viewed by educators as being disruptive and distracting, leaving kids less engaged in learning. They may even be damaging to students’ mental health.

Researchers at the University of Washington wanted to know what teenagers actually experience when using social media. The overwhelming answer? Boredom.

They learned this by surveying 25 teenagers multiple times a day about their emotional state while using Instagram. The survey results revealed that the teens largely logged onto the social media platform because they were bored; they felt bored while scrolling through their feed; and then eventually logged off because it was all just too boring.

The study says all this boredom was “punctuated by moments of social connection,” when they came across share-worthy posts and were able to send them along to their friends. The intermittent reward of social connection was what kept them going back to Instagram.

The research was presented at the ACM Interaction Design and Children Conference.

OPB science update: Agrivoltaics progress

Back in 2022, “All Science, No Fiction” featured a story about a radical new proposal to empower rural communities to lead the world in green energy production. The idea — called agrivoltaics — pairs agriculture and solar power production on the same plot of land, to the mutual benefit of both.

“I think the key words are: more food and better food, less water, extra revenue for the farm. It’s a four-way win for farmers,” Oregon State University agriculture professor Chad Higgins said in that story.

Now Higgins and an international team of researchers are looking at the impact the widespread adoption of agrivoltaics could have in the context of the United Nation’s sustainable development goals. The goals, adopted in 2015, are described as “a shared blueprint for peace and prosperity for people and the planet, now and into the future.”

The scientists found that agrivoltaic systems could be incorporated effectively to help meet many of these global goals — especially when it comes to ending hunger and providing access to sustainable energy.

Find more recent agrivoltaics research here.

In this monthly rundown from OPB, “All Science. No Fiction.” creator Jes Burns features the most interesting, wondrous and hopeful science coming out of the Pacific Northwest.

And remember: Science builds on the science that came before. No one study tells the whole story.