Palmyra -- An ancient city's tale of too much flouride

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An ancient city's tale of too much flouride

Posted 7/9/2006 7:15 PM ET

by Dan Vergno

 

As a waypoint on the ancient Silk Road, the metropolis of Palmyra had it all,

broad towers, impressive temples and enviable trade. Water from local wells even

contained fluoride, limiting that scourge of the ancients — tooth decay.

But just as the wealth of Palmyra vanished, leaving behind ruins in the Syrian

desert, a new study suggests its waters may also have been ruinous in the end

for the city's inhabitants.

Palmyra today is a World Heritage Site, a designation bestowed by the United

Nation Educational, Scientific and Cultural Organization in 1998. About 140

miles southeast of Damascus, the trading town known as Tadmor to the ancients,

later Palmyra, had been a center of trading since around 2000 B.C. But the town

really bustled during the Roman Empire, and was filled with magnificent

buildings throughout the 1st and 2nd century, starting during the reign of Roman

emperor Hadrian in 129 A.D.

He renamed the oasis town " Palmyra Hadriana. " Modest guys, those Roman

emperors. The city's wealth faded with the decline of Roman influence in ancient

Syria.

Starting in 1990, Japanese archaeologists have been excavating the Southeast

Necropolis of Palmyra and examining remains from the Roman era. Despite

Palmyra's prosperity, " skeletal remains uncovered from the underground tombs of

Palmyra have been found to retain an arthropathy of the joints, especially in

the knee joint, bone fracture, marked bone lipping, spur formation, and

eburnation (smoothed bone cavities), " reports the team led by Kiyohide Saito of

the Archaeological Institute of Kashihara in the current Journal of

Archaeological Science.

Fluoride in small concentrations is thought to deter microbes that cause tooth

decay, the reason why about 66% of public water supplies in the United States

are now fluoridated, according to the federal Centers for Disease Control and

Prevention. But the Palmyrans' symptoms, along with discolored teeth, point to

" fluorosis, " a skeletal and enamel-damaging syndrome caused by ingesting too

much fluoride over a long time, the researchers note. Looking at two large tombs

for example, 25 of 33 individuals (76%) had discolored teeth in one, and 45 out

of 65 (69%) had discolored teeth in the other.

Palmyrans drank, and still drink, water from wells tapped from ground water by

long tunnels called " qanats " (an excellent Scrabble word). The area's geology

and water table has been stable for about 7000 years, meaning water conditions

now aren't greatly different from those during Roman times. In a bid to estimate

the fluoride burden suffered by the town's ancient inhabitants, the researchers

analyzed the water from these wells. Fluoride levels were as high as three parts

per million in the water, a level that a National Academy of Sciences report in

March warned could lead to fluorosis.

To further check, the archaeologists also ground up seven discolored teeth

from tomb inhabitants, and compared them to seven others without discoloration,

to reveal their fluoride concentration. In a chemical reaction, fluoride tends

to replace some calcium in tooth enamel, making overexposure to fluoride

particularly worrisome for children with growing teeth and bones. The ground-up

teeth revealed that in the most discolored ones, about 22% of the calcium had

been replaced by fluoride. " Thus, it was possible to directly verify that the

ancient inhabitants of Palmyra did suffer from fluorosis, " they conclude.

Although the plight of these long-gone people may seem merely of academic

interest, concern about fluorosis exists today. U.S. Public Health Service

standards call for fluoridated water to not exceed 1.2 ppm in drinking water.

But about 200,000 people nationwide drink water with levels above 4 ppm, tapped

from wells naturally high in fluoride, according to the National Academy of

Sciences report. About 10% of kids in towns with these water supplies develop

severe tooth enamel discoloration from fluorosis, weakening their teeth. The

report also raised concerns about such high levels of fluoride being linked to

bone fractures, like those suffered by the ancient Palmyrans, but it did not

come to any final conclusions.

 

Each week, USA TODAY's Dan Vergano combs scholarly journals to present the

Science Snapshot, a brief summary of some of the latest findings in scientific

research. For past articles, visit this index page.

http://www.usatoday.com/tech/science/columnist/vergano/2006-07-09-palmyra_x.htm

 

 

LEARN MORE

Palmyra study abstract UNESCO entry on Palmyra

Syrian ministry of tourism site on Palmyra National Academy of

Sciences report on fluoridation (2006)

 

 

 

 

 

 

 

 

 

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