Archaeology’s poisonous past
Most U.S. ethnographic collections are contaminated with toxins. Will new cleaning methods help tribes reclaim artifacts?
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.
While museums have long been aware of the pesticide problem, tribes only discovered it as they began to reclaim artifacts under NAGPRA. Objects often arrived with lists of the frightening chemicals they might contain, from neurotoxic and lung-damaging mercury to carcinogenic arsenic; accompanying notes often warned against skin contact.
Soon after NAGPRA passed, for example, northern Arizona's Hopi won back a handful of sacred items, such as prayer sticks. Some were returned to individual families and others placed in grain storage devices to ensure a bountiful harvest. But testing later revealed that most were dangerously high in arsenic. The tribe issued a moratorium on repatriations, which remains in place today. "We only pursue something if we know it's clean," says Leigh Kuwanwisiwma, director of the Hopi Cultural Preservation Office, noting that this experience is common among tribes. "It's a huge obstacle to the full implementation of NAGPRA." And NAGPRA is already a long, disillusioning bureaucratic process: It took three years of negotiating for the Hoopa to obtain just 17 of the 52 relics they requested from the Peabody, and hundreds more are scattered among museums across the country, from a red deer skin in a Smithsonian storage room in Maryland to a stockpile of artifacts in a UC Berkeley warehouse. "I'm always asked by the council to go after more items," the Hoopa Tribe's Jackson says, "but I just keep telling them, 'Do you want to give me a toxic work environment?' "
Some larger museums and universities, such as San Francisco State, use federal funds to screen for pesticides and alert tribes to the dangers items might pose before they're returned. But even San Francisco State has pesticide troubles: In 2001, an environmental consulting firm found that the school's archaeological collection had left dangerous amounts of mercury in the anthropology department and museum.
Though a number of safety measures were implemented, in January the university's Old Science Building – which houses the museum and many anthropology labs – was shut down partly because of high levels of mercury and arsenic. University officials say the contamination emanated from broken thermometers, but researchers determined that archaeological collections were also likely to blame. More than 2,000 students and professors were displaced. One room, with mercury vapors 14 times higher than state safety limits, was padlocked shut and a Hazmat suit and respirator required for entry.
The building was emptied of artifacts and deep-cleaned.
There are some fairly effective methods for removing pesticides from artifacts without harming them, though they're all costly: Certain bacteria can draw out mercury by converting it into gas, lipolic acid removes arsenic from wool and feathers, and liquid carbon dioxide can flush synthetic pesticides from fragile materials. Now, though, the Arizona State Museum in Tucson is studying a new technique that uses water, with its pH adjusted using basic and acidic chemicals, to draw out specific heavy metals.
"It isn't simply, 'Wash it for three minutes and hang dry,' " says Nancy Odegaard, the museum's preservation division head, who is overseeing the effort, "but it also doesn't require an extensive amount of equipment." If it succeeds, tribes could easily clean certain items using little more than a faucet, latex gloves and a mask. The research is preliminary, but Odegaard hopes it encourages tribes to again aggressively pursue their sacred artifacts.
Carpenter, of the Hoopa cultural committee, hopes to soon retrieve more of the tribe's long-lost treasures. Each artifact remains an "old friend," even with mercury and arsenic present, he explains. "I wouldn't wear them, but our ancestors' spirits are in them. We're bringing their spirits home."
"They belong here," adds elder Walter Lara of the Yurok Tribe, whose reservation is just north of Hoopa and has similar traditions. Last year, Lara was discussing the return of another artifact housed at a Denver museum when he noticed a display containing a Hoopa white deerskin dress – one of the tribe's most sacred items.
When he sang to the dress, he says, it started moving. "I believe the spirit of that dress heard me and wanted to dance."