Archaeology’s poisonous past

Between the Trinity Alps and Humboldt County's coastal range, the Trinity River has carved a narrow, verdant valley in Northern California, where the Hoopa people have lived for thousands of years. Here, redwoods mingle with oaks, ancient traditions co-exist with modern amenities, and the reservation's small Hoopa Tribal Museum holds hundreds of treasures, from obsidian blades to intricately woven reed hats. Almost all of them can be checked out by members of the 3,000-person tribe and used in ceremonies. "The museum is for the people," museum curator Silis-chi-tawn Jackson explains. "It's not about the people."

On a warm February day, Jackson arranges a dozen Hoopa relics on a glass countertop for a handful of people to see. "What was this used for?" asks Charles "Chuckie" Carpenter of the Hoopa cultural committee, two long braids dangling as he points to a necklace made of shells and deer hooves. "I was told this is what Indian doctors wore," Jackson replies. "They didn't wear no big sign saying: 'I'm a doctor.' "

As Jackson examines a hide headband, small filaments break free into the air. "Whenever I touch anything," he says, "all of these little tiny feathers fly everywhere." Carpenter cautiously steps back.

That's because, unlike most artifacts at the Hoopa museum, these objects – all of them retrieved from Harvard University's Peabody Museum – are coated in dangerous amounts of mercury, arsenic, lead and DDT. Usually, the tribal museum keeps them wrapped in plastic and quarantined in a storage room. "Just working here, I consider it to be a health hazard," Jackson says, turning on the air conditioning for extra ventilation.

In the 19th and 20th centuries, state and national museums used more than 90 different pesticides on artifacts to protect them from bugs and rodents. As a result, an estimated 80 percent of all U.S. ethnographic collections are contaminated with heavy metals, posing health dangers to staff, visitors and, since the 1992 passage of the Native American Graves Protection and Repatriation Act (NAGPRA), to tribes who've sought the safe return of artifacts. "It's been the museum world's dirty little secret for decades," notes Peter Palmer, a San Francisco State University chemist and leading expert on the issue.

And it's an expensive problem to deal with: Because screening for toxins requires pricey equipment, cash-strapped tribes are often forced to simply isolate repatriated items. That's painfully ironic for the Hoopa, since handling artifacts and using them in ceremonies is supposed to ensure the people's longevity and health. New research, however, could make it easier for tribes to clean pesticide-laden relics. Jackson is excited: "If it works, it would be wonderful," he says. "These things were meant to dance, and now they sit in this box."

Before European settlement, religion united the Hoopa, and dancing was a form of prayer. The 10-day jump dance, for example, whose participants wore deer-hide headdresses and grass skirts, was held annually on the Trinity's banks to restore balance to the Earth. After gold prospectors arrived in the mid-1800s, though, these traditions were nearly lost. Mining pollution killed off the Hoopa's staple salmon; disease spread; children were sold as slaves. Many Hoopa people died prematurely; scores of other California tribes were exterminated. By 1900, the state's indigenous population had plummeted 60-fold, to 17,000.

As tribes struggled across the country, scientists began collecting the physical trappings of their lives, hoping to preserve the remnants of what they saw as vanishing cultures. Among the most dogged was Connecticut-born Charles Wilcomb, who dipped his finds in gasoline and mercuric chloride. The Oakland Museum of California now displays much of his collection, including Hoopa artifacts. "These would be dust without his secret formula," Louise Pubols, senior curator of history, says, showing century-old salmon skins and acorns. They're beautifully preserved and valuable to students, academics and tribal members. But they're stored in glass cases, and gloves and dust masks are recommended for handling.

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