The methods for detecting particular chemicals in any form—gas, liquid or particulate—are very specific. While the same sample of ice, water, or air may yield an entire suite of contaminants, how one kind is detected may not be compatible with measuring another. As Tom Harner, a senior scientist with Environment Canada who specializes in hazardous air pollutants, explained to me, “Every persistent organic pollutant is different and unique. Every chemical is a different story. Because each chemical is unique, we can’t investigate for a range of chemicals—we really have to do one at a time and look at each chemical’s diversity of properties.”
“We are seeing these chemicals in people and in biota where they shouldn’t be,” continues Harner. "Some of these compounds almost have two personalities. In one phase they can be hydrophobic—resist water and prefer to partition or attach to fat—and so accumulate in fat tissue, soil, and plant cuticles. In other phases they can be hydrophilic—be water-soluble—and be transported that way.” In other words, some compounds can hop, swim, and fly—behavior that is influenced both by the chemicals’ structure and the physical landscape and atmospheric conditions that surround them.
Asking questions about how a chemical’s structure will determine its behavior under various environmental conditions is a prerequisite of green chemistry. Had such questions been asked about PCBs or PBDEs— or had more attention been paid to the answers and their implications— they might not be turning up in birds cruising the northernmost fjords of Norway.
From Chasing Molecules: Poisonous Products, Human Health, and the Promise of Green Chemistry by Elizabeth Grossman. © 2009 Elizabeth Grossman. Reproduced by permission of Island Press, Washington, D.C.