You – yes, YOU – have PCBs in your body. Maybe a little, maybe a lot, but they are there. Why are PCBs classified as a known carcinogen in rats but only a probable carcinogen in humans? Who would benefit from that distinction? How could that distinction have ever been accepted (or not) by the scientific community? Want to know more? Then read on. Below is an extract of a research paper on PCBs done in 2002 for a course I took in Toxicology.
You can read the full research paper here and discover how PCBs are affecting us now and how they will potentially affect your great-grandchildren (yes, your GREAT-grandchildren). I promise it will be worth your time – Hudson
CASTLETON STATE COLLEGE, VT – PCBs (polychlorinated biphenyls) are a large family of chemical compounds (chlorinated biphenyls) once used as nonflammable, insulating liquids throughout the power-transmission industry (Kim et. al, 2001) as well as in lighting ballasts (Farrell, 1996) and some inks and carbonless copy paper (Hazardous Substances Data Bank – Full, 2002). PCBs were discovered late in the 19th century and because of their excellent insulating properties they were used extensively from the 1930s onwards as dielectric and heat-exchange fluids as well as in a variety of other commercial and industrial applications.
Human exposure to PCBs has largely been through contaminated food – particularly contaminated fish – and through contaminated water consumption but also through inhalation or dermal absorption of PCBs in occupational settings (WHO Working Group, 1993). PCBs are ubiquitous in the environment and people are not only exposed in occupational settings but their local environs as well (Ribas-Fita et. al, 2001). PCBs are highly lipophilic and enter the food web where they bioaccumulate in adipose tissue (WHO Working Group, 1993) and bioamplify up the food web (WHO Working Group, 1976).
There are measurable levels of PCBs in all human beings (Gauger et. al, 2002) and “the background level of PCBs in blood is approximately 20 parts per billion (ppb)” (Hazardous Substances Data Bank – Full, 2002), which is not to say that PCB levels in some human adipose tissue are not higher.
The commercial manufacture of PCBs ceased in the United States in 1977 (Hazardous Substances Data Bank – Full, 2002) and the 1976 estimate of worldwide production of PCBs from 1930 to 1976 was over 1 million tons. Of this amount it was also estimated that over one-half had entered dumps and landfills. Most of the remainder entered the environment via the disposal of industrial fluids directly into rivers, streams and / or coastal waters. PCBs do not break down quickly or easily in the environment (WHO Working Group, 1976).
Although now strictly controlled and monitored, PCB-contaminated materials were routinely discarded in municipal and private landfills for many years (Chen et. al, 1992) and PCBs, like many toxic chemicals now present in the environment, are not limited in their geographic distribution.
Read the entire research paper here…
Visit a site critical of GE here
Read GE’s surreal spin on things here
General Electric’s Credibility Problem
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