A 2,700-year-old drop toilet, found at an ancient royal estate in southern Jerusalem, still shows traces of what could have been an epidemic of parasitic infection long ago.
The findings suggest even the wealthiest inhabitants of ancient Jerusalem, elite enough to use an outhouse, commonly suffered from intestinal worms.
While latrines and toilets are considered basic sanitation facilities today, that might not have been their function thousands of years ago.
"The presence of indoor toilets may have been more a matter of convenience than an attempt to improve personal hygiene," archaeologists suggest.
"A toilet was a symbol of wealth, a private installation that only the rich could have afforded."
Mesopotamia is said to host the oldest known toilets in the world, roughly 6,000 years old. The historical region, which covered parts of modern-day Kuwait, Iraq, Syria, Iran, and Turkey, is known as 'the cradle of civilization' because it is home to some of the first farmlands.
As hunter-gatherers began to settle down into larger towns and cities, a designated area to poop was a must. For the average farmer, this probably meant going in a waste pit, but in some rare instances, wealthy individuals got more privacy. Judging from the archaeological record, however, private outhouses remained a luxury for many thousands of years.
The limestone loo in Jerusalem is one of the few that have been found. It was discovered in 2019, nestled in what appears to have been a carefully tended garden, right next to the remains of a large mansion filled with expensive items. It was probably owned by someone with great social standing.
The hole in the center of the stone seat suggests this was a basic drop toilet, with just a tank to catch excretion, but the view was something else.
From here, a squatter might have been able to view the City of David and the Temple Mount.
Archaeologists suspect the toilet seat was once surrounded by stone walls and possibly a roof, although the presence of airborne pollen from fruit and pine trees suggests there were probably windows or it was roofless. It could also be that the plants were used as a sort of air freshener.
However nice the small lavatory might have smelt, the presence of parasites suggests sanitary conditions at the time were poor.
Underneath the limestone toilet seat, careful analysis has revealed ancient sediment containing eggs from four different types of intestinal worms.
The eggs of roundworms (Ascaris lumbricoides) and whipworms (Trichuris trichiura) were the most abundant at the site. Both of these intestinal parasites can infect humans, leading to malnutrition and impaired growth in the most severe cases.
They tend to be transmitted when traces of human stool containing parasitic worms or their eggs are accidentally ingested. Once inside the intestine, the parasites are capable of producing thousands of eggs a day in their human hosts.
Without medicine, eradicating these infections in a population is incredibly difficult, especially without a clean system of poop disposal or hand washing facilities.
As such, the presence of roundworms and whipworms in the palatial poop of Jerusalem's elite suggests human feces were treated in unsanitary ways, possibly introduced into water sources, or dumped onto crops, before making their way back to our mouths.
Tapeworms (Taenia sp.) were also found in the fossilized cesspool, and because these parasites have an intermediate stage in beef and pork, they might have entered the human system via improperly cooked meat.
The final eggs found at the site were from pinworms (Enterobius vermicularis) – the earliest record of these parasites in ancient Jerusalem. Pinworms are spread via fecal contamination of the hands, but they can also float in the air.
Some researchers suspect these primate-infecting worms have been a nuisance for us since the very dawn of humankind, but since the eggs are extremely lightweight and delicate, they aren't often captured in the archaeological record.
Perhaps the use of closed-in lavatories spread these airborne infections even more.
Today, tapeworms, pinworms, whipworms and roundworms are still common infections throughout the world, but when medicine and sanitation facilities are available, they are easily treated.
Without these measures, however, intestinal infections like these can easily turn into epidemics, as appears to have been the case in ancient Jerusalem.
"Studies like this one help us document the history of infectious diseases in our area and provide us with a window into the lives of people in ancient times," says archaeologist Dafna Langgut of Tel Aviv University in Jerusalem.
The study was published in the Journal of Paleopathology.