The way to a human’s past is through their intestine - reconstructing diet and hygiene through paleoparasitological analysis at Lubelska 72A Street, Chełm (East Poland), in the 17th-19th century

Paleoparasitological analysis was conducted on soil samples from the sacral regions of human remains recovered during archaeological excavations at 72 A Lubelska Street in Chełm (Lublin Voivodeship, eastern Poland) dated to the 17th-19th century. The study yielded the most extensive dataset of its kind from the Early Modern period in the region. A total of 100 individuals—children, adolescents, and adults—were examined, and all samples tested positive for parasite eggs, with 1,106 specimens identified in samples derived from sacrum and 135 in control samples. Eight taxa were recorded; Trichuris spp. and Ascaris sp. were the most prevalent, while Oxyuridae and Dicrocoelium sp. occurred only in control samples. Polyparasitism was identified in 84 individuals, indicating frequent co-infections and potentially severe health effects. The exceptional preservation and high detection rate contrast with typical cemetery contexts, where such evidence is often scarce. Some trends in parasite presence by age and sex were observed, which may suggest possible differences in dietary or cultural practices. Dibothriocephalus spp. likely indicate true human infection associated for example with the consumption of undercooked fish, Fasciola sp. is also likely to represent true infection, whereas the presence of Macracanthorhynchus sp. more plausibly reflects spurious parasitism related to dietary practices. The abundance of Ascaris and Trichuris eggs points to fecal contamination, likely linked to the use of human or animal manure or to unsafe water sources, which may have led to true human infection. These results shed light on hygiene, health, and daily life in post-medieval Poland.