3D reconstruction of x-rayed worms. X-ray absorbing particles in the guts are shown in white.

Earthworms Don’t Bio-Accumulate Microplastics, So There May Be Hope For Us

May 5, 2026 by Tyler August 26 Comments

Microplastics absolutely saturate the Earth’s environment, and that’s probably not a good thing unless you’re looking for a sediment marker for the Anthropocene period. On the other hand, environmental contamination only becomes a really big problem if it bioaccumulates– that is, builds up in the tissues of plants and animals. At least when it comes to worms, that’s not the case with microplastics, according to new research from the Canadian Light Source at the University of Saskatchewan.

Pictured: Not an Igloo.
Credit: David Stobbe / Stobbe Photography, via University of Saskatchewan

The Canadian Light Source isn’t just some hoseheads in an igloo with a flashlight– it’s a 2.9 GeV Synchrotron tuned to produce high-energy photons. Back when Synchrotrons were used for particle physics, Synchrotron radiation was a very annoying energy sink, but nobody cares about 2.9 GeV electrons anymore. So rather than slam them into each other or a static target, the electrons just whip about endlessly, giving off both soft- and hard X-rays for material science studies– or, in this case, to observe the passage of polyethelyne microplastic particles through the guts of some very confused earth worms. To make them detectable by x-ray, the polyethylene was bonded to barium sulfate, an x-ray absorber. Equally opaque barium titanite glass microspheres were used with different worms, as a control.

Despite being fed soil enriched with far more plastic than you’ll find outside of a 3D print farm, it seems the worm’s digestive system was able to reject the particles, even those as fine as 5 microns. That’s a good thing, because if the worms were absorbing plastic from the soil, it’s likely their predators would absorb it from the flesh of the worms, so and so forth up the food chain in the sort of cascade that made DDT a problem and makes mercury compounds so serious. If the worms are rejecting these compounds, there’s a chance other creatures can too– and at the very least, it means they aren’t building up on this bottom rung of the foot chain. If you’re looking for a more technical read, the full paper is available here.

It’s too early to say what this means for how microplastics get into humans and other animals, but it’s hopeful. Equally hopeful was the recent finding that studies that don’t rely on football-field sized X-ray machines might be picking up on microplastics from lab gloves, skewing results.

Header image: the digestive systems of earth worms as imaged by the Canadian Light Source. Credit Letwin, et al,
Environmental Toxicology and Chemistry, vgag072, https://doi.org/10.1093/etojnl/vgag072

To See Within: Making Medical X-rays

May 12, 2016 by Dan Maloney 47 Comments

I was a bit of a lost soul after high school. I dabbled with electrical engineering for a semester but decided that it wasn’t for me – what I wouldn’t give for a do-over on that one. In my search for a way to make money, I stumbled upon radiologic technology – learning how to take X-rays. I figured it was a good way to combine my interests in medicine, electronics, and photography, so after a two-year course of study I got my Associates Degree, passed my boards, and earned the right to put “R.T.(R) (ARRT)” after my name.

That was about as far as that career went. There are certain realities of being in the health care business, and chief among them is that you really have to like dealing with the patients. I found that I liked the technology much more than the people, so I quickly moved on to bigger and better things. But the love of the technology never went away, so I thought I’d take a look at exactly what it takes to produce medical X-rays, and see how it’s changed from my time in the Radiology Department.

Continue reading “To See Within: Making Medical X-rays” →

Portable, DIY Radiography

December 31, 2015 by Brian Benchoff 31 Comments

[Matt] has a background in radiation, electronics, and physics, which means building a device to generate X-rays was only a matter of time. It’s something not everyone should attempt, and [Matt] discourages anyone from attempting anything like this, but if you’re looking for a project with a ‘because it’s there’ flair to it, building your own X-ray machine can be a fun and rewarding project.

Despite being scary and mysterious, X-rays are a rather old technology that date back to some of the first purposeful experiments in electronics. Most X-ray devices today are built around the same parts they were 100 years ago, namely, a Coolidge tube. Apply a high enough voltage to the Coolidge tube and electrons whizz from cathode to anode, and slam into a heavy metal target. This produces Bremsstrahlung radiation – ~~breaking~~braking X-rays – that can be directed to film or an X-ray intensifier screen that fluoresces in visible light when being struck by X-rays.

Aside from a cheap Coolidge tube, [Matt] constructed the rest of his X-ray generator with a voltage multiplier made out of sufficiently derated Chinese caps, a flyback transformer, and a transformer driver originally made for induction heating applications. The electronics were installed in a Tupperware container and insulated with mineral oil.

Being able to generate X-rays is one thing, viewing them is another matter entirely. For this, [Matt] is using an old X-ray intensifier screen from the 60s or 70s. This screen fluoresces blue, not the easiest color to photograph in low-light settings, but enough to capture images of the inside of tools sitting around his workbench. Following in the footsteps of [Roentgen], [Matt] also took an X-ray image of his hand. This is something he doesn’t recommend, and something he won’t do again, but it is a very cool example of what you can do with sufficient knowledge and respect for what can kill you.