These systems from Horizon
Technology are optimized for
EPA Method 608
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Developed
in the early 1900's, Polychlorinated biphenyls (PCBs) are
chlorinated oils that remain stable when subjected to heat and
pressure. These traits, combined with their high electrical
resistance, made them ideal for use in insulators, transformers and
capacitors. PCBs performed well in those initial applications and
their use expanded into hydraulic fluids, casting wax, carbonless
carbon paper, compressors, pigments, adhesives and fluorescent light
ballasts.
Polychlorinated biphenyls make up a group of 209 individual
chlorinated biphenyl rings know as congeners. A PCB is typically a
mixture of 60 to 90 congeners. As the number of chlorines in a PCB
mixture increases the flash point rises and it becomes less
biodegradable.
Once dispersed
into the environment, PCBs tend to concentrate, or bioaccumulate, in
animals at the top of the food chain.
Organochlorine
pesticides are insecticides composed primarily of carbon, hydrogen
and chlorine. They break down slowly and can remain in the
environment long after they are applied and in organisms long after
exposure.
The most
notorious organochlorine is the insecticide DDT (Dichloro diphenyl
trichloroethane). Promoted as a "cure all" insecticide in the 1940s,
DDT was used globally for many years in agricultural production and mosquito control.
For a copy of EPA Method 608,
click here
Click to download a
copy of a Horizon Technology Application Note on
EPA Method 608
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