Document 6wnM5nYK3RBmDELZnkzKXq0bg
Chemical Pollutants: Polychlorinated Biphenyls Still a Threat
Manufacturers and users of potentiulK toxic chemicals have argued that there no need for federal regulations to control their use. They contend that voluntary c<*ntrols and self-policing are adequate protec tion from potential hazards. This type i argument has generally been successful in preventing the passage of restrictive Ijv but the recent tecmergence of polychlori nated biphenyls (PCB's) us a major envi ronmental problem suggests that voluntary controls muy often be inadequate, even when the manufacturers apparently have the best of intentions.
PCB's are aromatic compounds con taining from 12 to 68 percent chlorine, Their high degree of stability and their low flammability make them ideul for muny in dustrial uses. These same properties, how ever. make the chemicals exceptionally
persistent in the environment-far more so. for example, than the chlorinated pesti cides such us DDT. Three years ago. the persistence and toxicity of PCB's in the en vironment had been fully recognized, and a variety of steps were taken that, it was thought, would bring the situation under control. In one of the most important vol untary actions, the Monsanto Company of
St. Louis, Missouri- the only U.S. pro ducer of PCB's- discontinued sales of the chemicals except for their use in electrical components. The Food and Drug Adminis tration also adopted an interim safety level of 5 pans per million (ppm) for PCB's in food, and the Environmental Protection Agency (EPA) issued waste disposal re strictions that were supposed to keep PCB levels below 0.01 part per billion in rivers and streams.
But these steps apparently did not pro duce ihc desired efTecl. The total amount of PCB's in the environment has not only not declined since then, but has apparently
increased substantially. According to Thomas E. Kopp of the EPA'X Office of
Toxic Substances, at least 4.3 million kilo
grams of PCB's are lest to the environ
ment each year through vaporization, leaks, spills, and burial in landfills. This is on exceptional amount considering that, last year. Monsanto produced only about IB million kilograms and another 170.000 kilograms were imported. Some 360 mil lion kiiogrums have been produced in the United States since 1957.
The most serious problems have been observed in the northeastern United States
and the province of Ontario. Both salmon and striped bass from the upper Hudson River and Luke Ontario, for example, have been found to contain PCB's in concentra tions from 5 lo 20 ppm, well uhove the 2*
ppm limit for edible fish adopted lust
II DllOsMil H l7S
month and the established U.S. limit. Sev-
.1 it investigators have reason to believe
*vt if a limit of l ppm were adopted, none <>l the fish in the Great Lakes would be ed.ble.
PCB concentrations nearly as high us hose observed in Great Lakes fish have Seen found, according toChurles R. Walk er of the U-S. Fish and Wildlife Service, in fish from such widely scattered areas as the Allegheny and Kanawha rivers in the East, the Tennessee and Missouri rivers in the Midwest, the Chena and Columbia rivers in Alaska and the Far West, and the Rio Giande. Alabama, and Mississippi rivers in the Gulf states. High concentra tions of the chemicals have also been found in waterfowl from the major U.S. flvuays and in other birds, such as sta lings, throughout the country. EPA Adminsi;utor Russell E. Train also says that PCB's have been found in the water supplies of Winnebago. Illinois, and Sellersburg. In diana. and that their presence is suspected in the water supplies of Bridgeport. Con necticut. Escondido. California, and New Bedford. Massachusetts.
Relrased Int* Rivers
The sources or this material are not completely known, but much obviously comes from manufacturing plants where PCB's are used. According to Robert Durfcc of Vesar Inc. of Springfield. Virginia, about 70 percent of Monsanto's PCB pro duction is used in electrical capacitors, while the remainder is used in trans formers. The EPA has. in fact, identified ten electrical component plums where PCB's are releused into rivers. In addition, one of these component producers and Monsanto itself have been identified by EPA as the sources of PCB's entering the sewage systems of Bridgeport, Con necticut, and Sauget, Illinois.
A good portion of the PCB's in the envi ronment must also come from the import ed materials, which are even more poorly controlled. Durfee says that some 80 to 90 percent of imported PCB's are used as plasticizers in waxes that in turn are used to form molds for producing high-quality metal castings. The remainder is used for what he terms "semicloscd heat transfer applications."
Other sources of environmental PCB's include the effluent from mills that recycle business forms and other paper products that were manufactured with the chemicals and smoke from the burning of such papers. Lesser amounts are also released from other products that contain small quantities of PCB's.
The health consequences of PCB's in the
environment are firmly established Mans
investigators have shown tSneme. 27 <)..
tober 1972, page 388) that PCB's tnicrtcrc
with reproduction in. for example, rodent!,,
fish, fowl, and primates. According to \s.
sistam Secretary of the Interior Nathaniel
P- Reed. PCB's may thus hasten the
tinction of endangered species despite our
best efforts to preserve them. He cites as .in
example the SI 75 million effort to restock
the Great Lakes with lake trout, splukc.
and salmon when those species had been
nearly wiped out by the invasion of sea
lampreys. Not only do PC BA interfere
with reproduction of the restocked fish, but
they also render those that survive inedible.
And if the fish cannot be consumed by
man. Reed argues, it will be difficult to jus
tify the expense of further elTorts to replen
ish them. Another species which he says is
directly endangered by PCB's is the bald eagle.
In animals fed PCB's. other ailments
have been observed. These include acne,
loss of hair, enlarged livers, gastrointesti
nal lesions, and abnormalities of the lym
phatic system. Furthermore. Renate D.
Kimbrough of the Center for Disease Con
trol has observed malignant liver tumors m
rodents fed diets containing 100 ppm of
PC B's. Her results have, however, not been
corroborated by other investigators.
PCB's also produce adverse effects in
man. Ailments such as those that occur in
laboratory animals fed PCB's have been
observed by Masanore Kumtsune of
Kyushu University in 1291 Jupanese per
sons who were affected by a 1968 incident
in which PC8's contaminated a batch of
cooking oil. In addition, workers using the
chemicals to manufacture capacitors at
two General Electric Company plants
north of Albany, New York, have com
plained of allergic dermatitis, nausea, diz
ziness. eye irritation, and asthmatic bron
chitis.
EPA contends that even though PCB's
are hazards, it does not have the power to
restrict or halt their production, to stop
their importation, or to prevent manu
facturing plants from releasing them into
waterways, ail of which may be necessary
to halt the threat to the environment. Train
thus argues that it is essemiui for Congress
to pass the Toxic Substances Control Act
now under consideration, which would give
EPA such powers. Passage of the act will
make it necessary to find adequate new
substitutes for PCB's in electrical com
ponents. But even if these measures are ac
complished. the PCB's that have already
been produced may still threaten the envi
ronment for a very long time.
--Thomas H. Mauim II
use
MONS 031879