Mummies from Chile’s Atacama desert ranging in age from 7,000 to 600 years old all show evidence of chronic arsenic poisoning.
The Atacama desert mummies are well-preserved by the near rainlessness of the environment, so a team of archaeologists from Chile’s Universidad de Tarapaca were able to analyze hair from 45 different mummies at ten sites in the area.
“Arsenic is a colorless, odorless and tasteless potent poison commonly found in contaminated rivers and in groundwater in many parts of the world, including the Atacama coastal desert region,” says the study. “We suspect that even the Chinchorro, the earliest inhabitants of this region, were already affected by arseniasis (arsenic poisoning) beginning 7000 years ago.”
In the research, the team cleaned hair samples with de-ionized water, and then blasted them with lasers for chemical analysis. Some modern-day waters in the region have arsenic levels 100 times higher than the 10 microgram-per-liter limits recommended by the World Health Organization.
About 31% of the mummies had arsenic levels above 2.6 micrograms per liter, the study finds, and 89% had arsenic levels at least a tenth of that concentration, enough to trigger health effects. “Our data show that ancient people of northern Chile accumulated significant levels of arsenic in their bodies,” concludes the study.
One 7000-year-old infant mummy had had a residue of 219 micrograms per gram, 20 times the WHO standard of toxicity.
The arsenic is naturally-occurring in the region. It leaches into the watershed from adjacent salt lakes and volcanic materials. Local populations drank the water, harvested riverbed plants, fished in the rivers and along the coast, hunted sea mammals and birds, and ingested huge quantities of arsenic in the process.
Chronic arsenic poisoning can result in stillbirths, skin and neurological disorders, cancer, cleft palates and spina bifida, among many other illnesses. It could very well be that wee mummy’s cause of death. Over 100 child mummies have been found in the Atacama desert near the city of Arica since 1983.