A Tribe Reveals Its Deadly Secret From the Grave : Sophisticated new tests indicate Omahas were decimated in the last century by poisoning caused by handling of lead.

Whites brought disease and war to American Indians during the last century and it took a heavy toll, but scientists here now think that at least one major tribe, the Omahas, may have been ravaged to near extinction by a stunningly different pioneer import.

“Why did they die?” poses anthropologist Karl Reinhard. “Subtle lead poisoning.”

In sophisticated new tests that could revise conventional notions of what decimated the natives of the Great Plains, researchers at the University of Nebraska recently examined the chemical contents of 40 skeletons exhumed years ago from Omaha tribal graves. More than half were heavily laced with lead, with concentrations in some cases far higher than that found in the bones of ancient Romans who were also believed done in by lead exposure.

The Omaha had more extensive contacts with whites than other tribes such as the Sioux and Pawnee and obtained lead in trade for a variety of uses, Reinhard explained.

By the early 19th Century, the Omaha had become the first gunsmiths of the Plains and probably swapped for lead to make musket balls. Artifacts found at the grave sites also suggest that traders may have supplied the Omaha with common, but unwittingly dangerous, items of the day, such as wine bottles and food tins sealed with lead solder and even baby pacifiers also made with lead. Additionally, some skeletons showed signs that men had used lead-based paint on their faces.

Once ingested, lead is absorbed into the bones and does not readily dissipate. Depending on the quantities and the age of those exposed, lead can cause retardation, developmental problems and even death. In the case of the Omaha skeletons, 22 of 40 exhibited lead in dangerous to lethal quantities ranging from 80 to 400 parts per million. The skeleton of one child even measured 1,000 parts per million.

Experts believe the skeletons were buried between 1780 and 1820 in what is now northeastern Nebraska. During approximately that time frame, the population of the Omahas began to dwindle from about 1,700 until it bottomed out at about 300.

Tribal history had blamed the decline on epidemics spread by white traders and settlers, a fate that is known to have befallen at least some tribes. But Reinhard said that the chemical analysis, conducted with mass spectrometers and other high-tech gear, showed surprisingly little evidence of infectious diseases on the Omaha skeletons.

Whether lead poisoning affected other tribes of the period is unknown and probably would not have been uncovered in the case of the Omahas, either, had it not been for an unusual resolution of a custody fight for the remains.

The Omaha skeletons were removed from their graves in 1939 and 1940 and had been held by the university ever since. For years, modern-day Omaha leaders demanded that the bones be returned to the tribe and finally prevailed upon the Nebraska Legislature to order such an action. In recent years, many tribes in other states have also mounted successful campaigns to regain control of ancestral remains from museums, universities and other research facilities.

Before taking the bones back, however, Omaha leaders asked the university to test them. The idea was to look for patterns of disease or nutritional problems that could have contributed to the 19th-Century die-off of Omahas and might shed some light on health problems that persist in the tribe to this day. The lead finding was a surprise.

“When those people died, old people died, medicine people died, people of history died,” explained Dennis Hastings, the Omaha tribal historian. “There was a void there. That history has now spoken to us through science.” The tribe finally took possession of the remains and reburied them last month.

Reinhard said the findings have implications not just for the Omahas, but for the broader population as well. “It signals to me that we have to be careful with our toxic elements today or we could end up like the Omaha of the 1800s,” he said. “Here we have a culture that almost went extinct because they had no knowledge of the toxic elements they were coming in contact with.”