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 water?

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 1961.

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 gravity.

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.
--Peter Montague, Ph.D.

Descriptor terms: history of pollution; culpability; responsibility; liability; groundwater; water pollution;