Archaeologists followed directions specified in the Dead Sea Scrolls and discovered the ancient latrines of the Essenes (one of the two groups believed to have authored the scrolls). There, they discovered that the Essenes' cleanliness rites (burying their waste, walking through a water pool en route to the shitter) actually caused them to have rampant parasite infections.
Two of the Dead Sea Scrolls note that the latrines should be situated northwest of the settlement, at a distance of 1,000 to 3,000 cubits – about 450 to 1,350 yards – and out of sight of the settlement.
Tabor and Joe Zias of the Hebrew University of Jerusalem, an expert on ancient latrines, went to the site and took samples.
Zias sent samples to anthropologist Stephanie Harter-Lailheugue of the CNRS Laboratory for Anthropology in Marseilles, France, who found preserved eggs and other remnants of roundworms, tapeworms and pinworms, all human intestinal parasites.
Samples from the surrounding areas contained no parasites. Had the waste been dumped on the surface, as is the practice of Bedouins in the area, the parasites quickly would have been killed by sunlight. Buried, they could persist for a year or longer, infecting anyone who walked through the soil.
(via William Gibson)
