Cloudy With a Chance of Deuterium
Day 118, 70-48
It was a cloudy and rainy morning (and day). The only thing on my mind while out for our "sunrise" walk was, "how much of this rain falling on me is deuterium?" I'm having difficulty committing a chunk of time to research this, so maybe we have to go bite-sized. On that note, just what is deuterium anyway?
Hydrogen comes in 3 flavors. The most common is protium, which has a single proton and no neutrons in it's nucleus. Much rarer is deuterium, which has a neutron in addition to the proton, and is hence twice as heavy! These are both considered stable forms of hydrogen, but that difference in atomic mas will become important later. Just to round things out, there is also tritium (one proton and TWO neutrons), which is exceedingly rare, and a good thing too, as it is radioactive. Per Wikipedia, protium is 99.98% of all the hydrogen atoms on earth and deuterium is 0.0156%, and tritium much less than that. There are ways to make deuterium, but for the most part what we have has been here since....The Beginning (cue spooky music and lightning).
A water molecule is composed of one hydrogen atom and two oxygen atoms. That hydrogen can be either protium or deuterium (or tritium, for that matter). The ratio in water closely matches the ratio of hydrogen as a whole. So for the most part our water is plain old water. But a small amount of it is "deuterated", or heavy water. The interesting thing is that because of the difference in atomic mass, as well as atomic spin characteristics, it may reach higher concentrations in certain circumstances due to gravity or retention by different plant or animal cells. This is where things get hairy. Many experiments have been done exposing plants and animals to high concentrations of heavy water. The results are typically detrimental to all sorts of cellular processes. Hence all the ads for "de-deuterators" on diner paper placemats and in the backs of magazines. But before we get all worked up, the risk of serious toxicity or death from heavy water is very low, as the concentrations would have to be very high, like 25-50% of total body water (Wikipedia). You would have to chug direct from the tap at a production facility to even get close (don't do this, and talk to your doctor). While major death or disability is unlikely, there is at least theoretically potential for sublethal adverse effects, as deuterium does have signaling properties within the body that are important in early development, but may be deleterious in adulthood. And deuterated water concentration does vary between water and food sources.
And that is where I'll end for now to leave you hanging for tomorrow!