# Medieval Trondheim's latrine waste rules spread roundworm via crops, NTNU archaeologists report

- Published: 2026-11-13 13:09 UTC
- Section: Life & Health › Biology & biochemistry
- Tags: medieval Trondheim, roundworm infection, latrine waste, miasma theory, MedHeal600, NTNU University Museum, medieval sanitation, Nidaros, bioarchaeology
- URL: https://realtech.media/news/rt-339d6c633cae24fb04e5313e_medieval_trondheim_s/

**Archaeologists of the NTNU University Museum found that Trondheim's medieval rules to move latrine waste out of town fed a cycle of roundworm infection among nearly all residents.**

![Medieval Trondheim's latrine waste rules spread roundworm via crops, NTNU archaeologists report](https://realtech.media/media/2026/11/ac15a27fcb8f5269.jpg)
*Portable Antiquities Scheme, Wikimedia Commons, CC BY 2.0*

Archaeological work in Trondheim, Norway, shows that municipal sanitation reforms of the Middle Ages unintentionally exposed residents to widespread roundworm infection, according to bioengineer.org's report on the MedHeal600 project led by the NTNU University Museum. [1] As the city grew between 1130 and 1350, authorities began to regulate hygiene, street clearance and waste disposal, moving them from private household matters into a civic framework. [1]

## Latrine waste and the miasma theory

The project "Medieval Urban Health: From Private to Public Responsibility AD 1000–1600" studied health and living conditions in medieval Trondheim, then called Nidaros, over six centuries. It was led by Axel Christophersen, professor emeritus of historical archaeology. [1] Responsibility for collective welfare was set out in King Magnus the Lawmender's Landslov of 1274 and the Bylov of 1276, with royal officials overseeing the work. [1]

Under the miasma theory, foul smells from decomposing refuse and latrine waste were believed to cause epidemics. Trondheim authorities therefore decreed that human excrement should no longer accumulate on residential plots. It was to be collected and taken to disposal pits outside the urban perimeter, separately from domestic refuse. [1]

Excavations analysed by Elisabeth Forrestad Swensen confirmed that latrine waste was never mixed with ordinary garbage. Inhabitants blended household refuse with wood shavings and sawdust, which dampened odors. [1] Analyses of material from the external latrine pits showed that nearly the entire medieval population was infected with roundworms. Swensen established that the waste was incorporated into agricultural manure, where roundworms thrive. Spread on fields, it contaminated crops grown for the city, and residents who ate them swallowed the parasite eggs again. [1]

## Wood shortage and social differences

Toward the end of the thirteenth century the volume of wood chips fell sharply. Researchers link this in part to the 1257 volcanic eruption in Indonesia. [1] Locally, centuries of construction had depleted the timber around the settlement, and migration stagnated and house building essentially ceased around 1300. [1] Without sawdust, the street-side refuse pits became intensely offensive, and all organic domestic refuse began to be hauled outside the city. [1]

Skeletal remains from Trondheim cemeteries indicate that well over half of the population suffered acute physiological stress in childhood and adolescence. Researchers point to malnutrition and monotonous diets, with leprosy, typhoid fever and tuberculosis among the endemic diseases. [1] A cemetery beneath the modern Trondheim Public Library held the city's commercial elite, who ate diverse diets rich in fish and seafood. A cemetery across the street, in the craft workers' quarter, showed higher child mortality, poorer skeletal health and less varied nutrition. [1]

The Black Death arrived in the mid-fourteenth century. Professor Erik Opsahl noted that the long-term contraction resulted from repeated plague outbreaks rather than a single uninterrupted decline. [1]

## Sources

1. [bioengineer.org](https://bioengineer.org/medieval-trondheim-sanitation-reforms-unintentionally-spread-parasitic-roundworm-infections-through-crops)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-339d6c633cae24fb04e5313e_medieval_trondheim_s/