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.
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Add CommentFor decades legally acceptable levels of discharged pollutants in air and water have relied on the notion that as they go downstream they will become diluted to ever safer levels. This is to ignore that once in the oceans, these pollutants will be concentrated back up through the food chain to toxic levels. Therefore the only acceptable dilution is zero discharged pollutants. Waste effluents should logically be dried and deposited in safe landfill sites where like naturally occurring toxic mineral ores they can do little harm.
Reply | Report Abuse | Link to thiseco-steve
Reply | Report Abuse | Link to thisAll your ideas that I've read so far are really good.
Could you e-mail your idea... maybe someone, in the right place, will think, Better idea... and put your thoughts in practice. Can't hurt to try.
Great things are not done by impulse,
but by a series of small things brought together.
By Vincent Van Gogh
eco-steve
Reply | Report Abuse | Link to thisSorry to tell you that, it is not so simple. Drying waste use huge amount of energy and will vaporise what can be vaporise. Then you have to find apropriate landfill that will not leachate, without worried neighbours...
People fixing legally acceptable levels of pollutant know that no level is guarantee to be safe. It is just the best we can get. No government can ask the industries not to pollute. Its only a balance between what price you are willing to pay and what risk you can accept. A lot is being done with waste treatment and I think green design is the next step.
Zero discharge is a good dream. Keep dreaming, good changes begynn with good dreams.
Sybil : Drying waste certainly can be energy-hungry. Yet a lot can be done simply. First of all ensure no rain falls on effluents, and that waste is properly held in flood-free tanks and reservoirs. For example, the china clay industry in England was forced, (Yes, by massive fines), to build settling beds downstream of their quarries. Overnight pollution stopped. The settling beds were built so wind dried them. Industrial wastes are often potential raw materials for other uses. Think about sewerage sludge which can be used as fuel by cement ovens, which can also incorporate toxic wastes to seal them virtually forever.
Reply | Report Abuse | Link to thisThe problem of lixiviation will be cracked when once properly conceived landfill sites are optimised. The main problem is that many firms find it cheaper to dump waste rather than to treat it legally.