Analysis of combustion fireplaces in houses at the Çatalhöyük site in Turkey indicates that the owners were exposed to levels of pollution incompatible with current standards.
The historic site of Çatalhöyük is still being excavated.
The Çatalhöyük site has been listed as a UNESCO World Heritage Site since 2012 in view of its historical importance. It bears witness to more than 1,000 years of continuous occupation between 7100 and 5700 BC. With, in the most prosperous periods, up to 8,000 inhabitants sharing their resources. Numerous archaeological excavations have been carried out there and still are. This time, a study focuses on the indoor pollutants that these Neolithic men were already breathing.
Indoor pollution in Neolithic houses
Life in Çatalhöyük was organized in neighborhoods populated by small houses of 15 to 25 square meters. They were all built on the same model:a central room with a domed oven attached to the south wall and a more central hearth location. Then, in the rest of the room there were raised platforms. They were, like the walls, covered with plaster whose previous analyzes had already revealed the presence of soot deposits which were regularly covered by a new layer of plaster. These habitats were occupied for about 70 years before being destroyed to be rebuilt in the same place.
Archaeologists from the University of Newcastle (United Kingdom) have teamed up with environmental engineers to study the indoor pollution of these houses by fine particles released by the oven and hearth. They focused more specifically on those of 2.5 microns (PM 2.5), a major cause of air pollution in our modern societies.
High levels in the air
To carry out this work, the scientists used a replica of a house built in the late 1990s and intended for visitors to the site. They burned different types of fuels there and then measured the levels of PM 2.5. The results, published in the journal Environmental Geochemistry and Health , indicate that the average particulate levels over a two-hour period were extremely high and that concentrations remained high for up to 40 minutes after the lights went out. All the fuels used lead to dangerous levels of particles, but it is manure or combinations of manure or wood that produce the most, sometimes with levels exceeding the capabilities of the detector! That is more than 150,000 micrograms per cubic meter. The absence of a chimney and the single room are the factors that seem to be the most important in explaining these very high rates.
Overall, the authors estimate that residents of Çatalhöyük were exposed to dangerous levels of PM 2.5, above current European Union and WHO standards (which are 25 and 10 micrograms per cubic meter respectively). year). What, therefore, cause, according to current knowledge, respiratory pathologies and an increased susceptibility to infections. Many skeletons discovered at the site show signs of osteoperiostitis (an infectious disease of the bones) and arthritis which could be linked to this exposure to PM 2.5. However, these diseases are not specific enough to be certain. Researchers therefore call for more archaeological studies to explore the impact of the built environment on health and lifespan.