PCBs AND ASSOCIATED AROMATICS 849
Chick edema disease was linked to PCB exposure when
chicks were placed in galvanized cages that were coated
with an epoxy resin paint. The paint had not hardened prior
to placing the chicks in the cages, and within three weeks
the chicks showed symptoms resembling those that had been
reported as chick edema in incidents resulting from toxic
components in chicken feed [McCune et al., 1962].
Chick edema disease was linked to PCB exposure when
chicks were placed in galvanized cages that were coated with
an epoxy resin paint. The paint had not hardened prior to
placing the chicks inside the cages, and within three weeks
the chicks showed symptoms resembling those that had been
reported as chick edema in incidents resulting from toxic
components in chicken feed [McCune et al., 1962]. Aroclor
1242 was determined to be the causative agent. Prompted
by this initial finding, further studies on the effects of PCBs
in chicks were conducted. Studies on chicks fed Aroclor
1242 showed high mortality, hydropericardium (accumula-
tion of water in the sac that surrounds the heart), hemor-
rhagic edematous lungs (abnormal swelling from blood and
fluid accumulation in the lungs), kidney tubular dilation
and lesions, swollen liver, and a dose-dependent pathology
[McCune, 1962; Flick et al., 1965]. Growth rates of chicks
were slowed in a dose-dependent manner and defeathering
and dermatitis were reported [Flick et al., 1965].1963A study with chick embryos showed 0% hatchability in
high Aroclor 1242-dosed embryos. Embryo’s showed beakdeformity, edema and growth retardation [McLaughlin
et al., 1963].1966In 1966 the American Conference of Governmental Industrial
Hygienists amended their description of the suggested limit
of “Chlorodiphenyl—42% Chlorine—Skin” and stated that
“Acne is not an invariable warning sign of impending, more
severe, systemic toxicity” (Figure 8).
Jensen identified Aroclors 1254 and 1260 while analyzing
for DDT [Jensen 1966]. He detected the presence of certain
unidentified peaks in specimens of white-tailed eagle feathers
dating as far back as 1942. Since DDT was used widely as a
pesticide only after 1945 it was apparent that the pesticide-like
chemical found in the samples was not a DDT break-down
product, DDE or DDD. In 1967 G. Widmark unambiguously
identified the contaminants as PCBs using MS.
The initial work by Jensen (1966, 1969) and of
Risebrough (1968) sparked an immediate concern that PCBs
had become ubiquitous in the environment. The information
was reported in the San Francisco Chronicle of February
24, 1969. In an open letter to Monsanto’s customers, the
Environmental Health department, gave a cautious overview
of the findings on March 3, 1969.1967G. Widmark published “IUPAC Commission of Methods
of Pesticide Analysis: Possible Interference by PCBs.”FIGURE 8 Widespread contamination by these compounds complicated the
analytical quantitation of PCBs.C016_003_r03.indd 849C016_003_r03.indd 849 11/18/2005 1:12:23 PM11/18/2005 1:12:23 PM