When someone in industry claims that they contributed to the creation
of a Superfund site by dumping toxics into the ground, but did it out
of ignorance, what is the truth behind such claims? When some polluter
says, "I didn't know. It's not my fault. Twenty years ago, no one
knew," can you believe them? When did people really understand that
dumping chemicals into the ground would contaminate soil and subsurface
Human knowledge of toxicity has its roots shadowed in the mists of
time. Prehistoric humans no doubt understood that some fruits and
berries are toxic and others are not. There were practicing
toxicologists in early Greece and Rome, selling their wares to would-be
murderers and suicides. They sold chiefly vegetable potions that killed
or injured their victims, but they also sold arsenic. The toxic
properties of lead and mercury were understood by the Romans, but they
did not come into use as intentional poisons until the renaissance
(14th through 17th centuries).
Between 1830 and 1880 the field of "organic chemistry" developed and by
1880, 12,000 compounds had been synthesized. The goal was to create
dyes, solvents and pharmaceuticals, but many of the new chemicals were
toxic and sometimes the chemists themselves were killed by their
creations. This quickly led to the practice of dosing dogs and cats
(later rats and mice) with new chemicals, to reduce the need for
experiments on humans in the laboratory and in the workplace.
By the mid-1930s, three major chemical firms (DuPont, Dow and Union
Carbide) had established their own laboratories of industrial
toxicology where they systematically looked for toxic effects of the
chemicals they sold. Others soon followed suit because it made good
business sense not to poison your workers or your customers--at least
not to poison them so they died right on the spot. The effects of long-
term, low-dose poisoning were always hard to detect and hard to prove,
and many industrial leaders have been willing to wink at this sort of
poisoning from earliest times.
It is simply not true that people 20 years ago did not understand the
toxicity of chemicals. If you want exhaustive proof that people have
understood the toxic properties of modern chemicals since the early
1900s, you have only to glance through a book like Donald Hunter's The
Diseases of Occupations. The third edition of Hunter's classic appeared
in 1964, 24 years ago and among its 1225 pages one can find early
knowledge of every chemical we are concerned about today. Benzene
toxicity was first reported in 1897. Phenol toxicity was reported in
the 1880s. Cyanide toxicity was well understood in 1934. The toxicity
of halogenated organic compounds (chloroform, trichloroethylene, carbon
tetrachloride, for example) was reported extensively in the 1930s. And
on and on.
But what about the relationship between polluted water and human
disease? How long has that been recognized?
In 1854, 134 years ago, the greatest pollution disaster of modern times
struck the city of London, England. Nearly 20,000 people died of
cholera in two separate epidemics. Scientists and doctors of that time
had no idea that bacteria and viruses caused disease, and it would be
another 25 years before that discovery was made. Despite this important
gap in knowledge, careful detective work in 1854 pinpointed sewage-
contaminated drinking water as the source of the cholera outbreaks, and
public health measures were instituted to prevent epidemics from
recurring. Physicians and scientists throughout the western world have
recognized ever since that clean water is essential to human health.
In 1906 the U.S. Geological Survey published its first paper on the
prevention of groundwater contamination by careful well construction.
By 1910 the Survey published its recommendation that dumping garbage
and other filth into sinkholes in limestone be abandoned because the
practice was contaminating groundwater.
Throughout the first half of the 20th century, Americans conducted
studies of water contamination. As early as 1923, researchers injected
dye into the soil along with bacteria, indicating that bacteria did not
flow through soil as far as chemicals did. In 1937 in Alabama, another
study showed that chemical pollution traveled through soil farther than
bacteria. Bacteria seemed to be filtered out by soil, but chemicals
were not. Two additional studies in 1938 confirmed these findings. More
dye studies in 1957 confirmed these findings once again.
In 1952 a task force of the American Water Works Association surveyed
state governments for evidence of groundwater pollution. In 1953 the
task force reported, "although ground water pollution by industrial-
waste disposal is reported as relatively minor in many states, and even
non-existent in some, it is, nevertheless, nationwide in distribution."
Specific compounds mentioned as contaminating groundwater in 1952 and
1953 were gasoline, phenols, picric acid, and cleaning fluid. When the
same task force surveyed the states in 1957, 47 states replied and 42
of them reported groundwater contamination. Clearly the problem was
growing or awareness of the problem was growing, or both. By 1960 the
task force found the following chemicals contaminating groundwater in
the U.S.: creosols, 2,4-D (a pesticide), dichlorophenol, gasoline,
hexachlorocyclohexane, hydrocarbons, kerosene, pentachlorophenol,
phenol, picric acid, pyridine, and trichloroethylene.
The modern era had clearly arrived. In 1960.
The U.S. Public Health Service sponsored a national conference in
April, 1961, entitled "Ground Water Contamination." Attendees at the
conferences reported all the pollution facts we've given above, and a
great deal more. In fact, the 1961 report of the conference makes it
crystal clear that the entire problem of groundwater contamination from
chemical waste disposal, and from landfilling of municipal wastes, was
well known, well documented, and the subject of urgent warnings in
The picture in 1961 was basically as we know it today:
Near its surface, the earth is made up of soils that contain small
amounts of water, but which are not saturated. About 30 feet below the
surface (more in some places, less in others), you run into a saturated
zone. This is groundwater; it is like a large lake. It flows toward the
sea very slowly (two feet per day to two feet per year), pulled by
Chemicals dumped onto or into the soil are pulled downward by gravity
until they run into the groundwater table (the upper surface of the
saturated zone), at which time they start moving horizontally with the
groundwater. Dilution does not take place in groundwater as it does in
a turbulent stream, and there's little oxygen, so groundwater remains
contaminated for long periods. Furthermore, cleanup is difficult at
best, and usually impossible, so groundwater contamination must be
thought of as essentially permanent.
In 1961, geologists said that 95% of the nation's surface waters were
already in use and that future drinking water would have to rely on
clean supplies of groundwater. They urged that pollution be stopped.
Descriptor terms: history of pollution; liability; groundwater; water