250,000-Year-Old Neanderthal Tooth Found to Have Lead Exposure

This study is the first to report lead exposure in Neanderthals and is the first to use teeth to reconstruct climate and timing of key developmental events, including weaning and nursing duration — key determinants of population growth.   (Image: via   pixabay  /  CC0 1.0)
This study is the first to report lead exposure in Neanderthals and is the first to use teeth to reconstruct climate and timing of key developmental events, including weaning and nursing duration — key determinants of population growth. (Image: via pixabay / CC0 1.0)

Using evidence found in teeth from two Neanderthals from southeastern France, researchers from the Department of Environmental Medicine and Public Health at the Icahn School of Medicine at Mount Sinai report the earliest evidence of lead exposure in an extinct human-like species from 250,000 years ago.

This study is the first to report lead exposure in Neanderthals and is the first to use teeth to reconstruct climate and timing of key developmental events, including weaning and nursing duration — key determinants of population growth. Results of the study were published in Science Advances, a journal published by the American Association for the Advancement of Science.

A 250,000-year-old Neanderthal tooth yields an unprecedented record of the seasons of birth, nursing, illness, and lead exposures over the first three years of this child’s life. (Credit: Tanya Smith & Daniel Green)

A 250,000-year-old Neanderthal tooth yields an unprecedented record of the seasons of birth, nursing, illness, and lead exposures over the first three years of this child’s life. (Image: Tanya Smith & Daniel Green)

The international research team of biological anthropologists, archaeologists, earth scientists, and environmental exposure experts measured barium, lead, and oxygen in the teeth for evidence of nursing, weaning, chemical exposure, and climate variations across the growth rings in the teeth. Elemental analysis of the teeth revealed short-term exposure to lead during cooler seasons, possibly from ingestion of contaminated food or water, or inhalation from fires containing lead.

During fetal and childhood development, a new tooth layer is formed every day. As each of these “growth rings” forms, some of the many chemicals circulating in the body are captured in each layer, which provides a chronological record of exposure. The research team used lasers to sample these layers and reconstruct the past exposures along incremental markings, similar to using growth rings on a tree to determine the tree’s growth history.

This evidence allowed the team to relate the individuals’ development to ancient seasons, revealing that one Neanderthal was born in the spring and that both Neanderthal children were more likely to be sick during colder periods. The findings are consistent with mammals’ pattern of bearing offspring during periods of increased food availability.  The nursing duration of 2.5 years in one individual is similar to the average age of weaning in preindustrial human populations.

The researchers note they can’t make broad generalizations about Neanderthals due to the small study size, but that their research methods offer a new approach to answering questions about long extinct species.  Christine Austin, Ph.D., Assistant Professor in the Department of Environmental Medicine, Public Health at the Icahn School of Medicine at Mount Sinai and one of the study’s lead authors, said:

Manish Arora Ph.D., BDS, MPH, Professor and Vice Chairman Department of Environmental Medicine and Public Health at the Icahn School of Medicine, said:

The study’s lead author, Tanya Smith, Ph.D., Associate Professor at Griffith University, added:

Provided by: The Mount Sinai Hospital [Note: Materials may be edited for content and length.]

Like this article? Subscribe to our weekly email for more!     

Mechanical Water Toys
IBM Is Buying Red Hat for a Whopping $34 Billion
#article-ad-block-->