Music
Ambience: Butter Churning
That’s the sound of butter being churned the old fashioned way. Well, butter is being used by scientists worldwide to churn up some useful information about chemical pollutants. I’m Jim Metzner and this is the Pulse of the Planet. Dr. Kevin Jones is a professor of environmental science at Lancaster University in England. To monitor pollution, he and his colleagues have analyzed butter samples collected from farms all over the world.
“We analyzed these hundred or so samples for lots of different chemicals. Some were pesticides; some were industrial chemicals. And then we were able to make maps of the distributions of these chemicals in different places. We also did some studies where we took several butter samples from within one region, just to be sure that that was fairly homogeneous, if you like, and that we were able to look at consistency in one area, and to statistically show it was different from what we were finding in other locations. We found very big differences in the concentrations of some of the chemicals we were looking at. For example, the old organic chlorine pesticide DDT, I think we had something like a hundredfold difference in the concentration between the most contaminated butter samples and the cleanest samples we could find. But we also found some very interesting differences between the chemicals. We were able to make inferences about the ways in which chemicals are spreading from their source areas into more remote parts of the world. So, for example, for chemicals that have been around for a very long time, they’ve become more dispersed, more evenly distributed in the environment. For this kind of work, we think it’s important to try and obtain the samples as close as possible from the source. So, we would go directly to the farms or we would ask our colleagues or collaborators in different countries to approach local dairies or local farmers to obtain the samples. We’re concerned that obviously with modern agriculture and modern food production, a trend has been to collect large volumes of milk, homogenize those or mix those at very large dairies, and obviously by doing so, uh, you’re integrating the chemical burden from a very wide area. So we want to avoid that practice for this particular study.”
But how much about our environment can we really tell from these butter samples? We’ll hear more in future programs. Pulse of the Planet is made possible by the National Science Foundation. I’m Jim Metzner.