Environmental Engineering Reference
In-Depth Information
It is rarely recognized that big steps in science are often made possible by the avail-
ability of a new type of technology. In the ozone chapter, we learned how James Lovelock
designed the electron capture detector, which was capable of measuring very small concen-
trations of trace gases. This advance enabled chemists to measure such substances as DDT,
PCBs and freons at picogram levels of concentration. Therefore, we should probably also
be thanking James Lovelock for opening this door to modern environmental chemistry.
PCBs were first synthesized in Germany in 1881 and were soon put to a wide spec-
trum of uses, which included hydraulic oils, flame retardants, pesticides, coolants, paints
and sealants. Concerns about their toxicology grew from the 1930s, and by the early 1970s,
most European and North American countries banned all uses except when they were con-
strained in closed systems. By the end of the 1970s, most of these same countries had aban-
doned production and import, but use of PCB-containing fluids in existing equipment, such
as transformers, was still allowed.
Returning to the Arctic situation, where were these chemicals coming from and were
the levels significant?
Garth organised a small monitoring programme to help provide answers, and by late
1988, he had some preliminary data on his desk. Michael Wong's report and Garth's first
data set were also “game changers” for me. Reorganisation in 1988 took me into Garth's
directorate and we set about solving the puzzle until he took off for more lofty responsib-
ilities and even hotter potatoes a few years later. Russel Shearer joined my group at about
this time, and together, we gathered a wonderful team over the next 15 years, with Kathy
Adare, Jennifer Baizana, Siu-Ling Han, Jill Jensen, Sarah Kalhok, Marilyn Maki, Janine
Murray, Carol Reynolds, Simon Smith, Jason Stow and Jill Watkins.
At the end of February 1989, Garth set up a science evaluation meeting in Ottawa
to examine his data set. More than 40 specialists from North America, Northern Europe
and the Soviet Union participated. Very few direct air or water measurements were avail-
able to reveal the pathways taken by the contaminants to reach the Canadian Arctic. It was
known that radionuclides, acidifying substances and some metals from industrial activit-
ies were being transported in the atmosphere from sources outside the Arctic. There was
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