In this case, we take the water collected in Montana, back to our labs in Virginia, where we look at the samples in a transmission electron microscope (that is, a TEM). I’m standing with the very instrument we use in the picture. It huge, with the microscope itself and necessary associated equipment taking up a large size room. It is extremely expensive to purchase (millions of dollars), and using it requires a great, great deal of expertise and training, as you can imagine. The system is so complex that it takes a great deal of knowledge just to keep it running. Yet, these remarkable instruments allow you to “see” with magnification up to a million times or so. That’s good enough to see single columns of atoms, if you can believe that. Nanoparticles may only be a few tens of atoms across, so you need an microscope of this power to see and study them. Thus, a high resolution TEM like this one becomes an essential tool.
That’s me, standing in the headwaters of the Clark Fork River, taking water samples. The toxic heavy metals are in this water, all right, but in what form? That’s important if you are a fish, or a human, or a water plant, or a bacterium. Take lead for instance, a highly toxic metal. Is the lead dissolved as atoms of lead in the water, or as part of the fine minerals and organic compounds that make up the stream bed, or perhaps something else. That something else is where we come in. We have found a significant portion of the lead to be held in what we call “nanoparticles”, unbelievably small mineral particles that contain lead. What’s most interesting for scientists is that because these particles are so small, basically the size of single molecules, they have unusual characteristics, behaving differently in nature than the same particles, except bigger. This is really the basis of nanoscience and technology, a relatively new field of science that is taking the world by storm. This is because nano-things have such interesting characteristics, many useful for our exploitation, that they make a big difference in everything from modern fabrics to suntan lotions to computers. So as we observe and learn more about nanoparticles that contain lead (and other toxic metals) in these river waters, we will have a much better understanding about how fast they travel downstream from the contaminant source, and how and why they affect living things.
Look at the picture at the very top of this blog. It is the Clark Fork River as it winds its way through the Ponderosa Pine forests of western Montana towards to city of Missoula. The Clark Fork is one of many spectacular rivers in this remarkably historic and scenic state, with many stories to tell. There was Glacial Lake Missoula thousands of years ago during the last ice age, Indians taming and caring for this land for many centuries , Lewis and Clark trekking through just two hundred years ago, and within the next century after that, some of the most intense base metal mining in the world. And today, there is a modern society that calls these hollowed lands “the last best place”. And they are riight . . . Montana is magical, wild, and with a look and feel all its own, from the wide open, big sky prairies far to the east, to the rugged and wide-open wilderness of the west. And as the fourth largest state, there’s a lot of both!
And what has all this amounted to? Like anywhere else, human habitation and use has been good, and not so good. In the latter category, a century and a half of mining in the Butte, Anaconda area has created the largest Superfund Complex in the United States. Approximately 1,600 square kilometers of land are seriously contaminated with excessive amounts of copper, zinc, lead, and arsenic, not good if you happen to be a living organism. Local, state, and federal officials, not to mention the citizens of this great state, want the contamination issues resolved. That’s where we, as Earth scientists that study the environment, come in. Our job, collectively, is to figure out what nature with man’s overprint has given us, and how the system works. Then it’s up to politicians, citizens, lawyers, engineers, and business leaders to do something about it.