A study confirms the concern that had started a Roman bowl in poor condition, spoiled by pesticides that accumulate in the soil. The paper demonstrates how a modern pesticide, chlorobenzenes, can pose a continuing threat to the conservation of still-buried archaeological material.
Scientific Reports yesterday published the study by a team from the University of Oxford. The conclusions affirm a direct relationship between the level of chlorobenzenes in the soil and the increase in corrosion of the archaeological container, a Roman bowl from the last stage of the Iron Age.
Chlorobenzenes are a chemical that was used in pesticides. They have been frequently used in agricultural and industrial activities, and that is why they are found accumulated in the soil and in water sources. These compounds are harmful to the environment while also endangering the integrity of archaeological remains of great historical value.
In fact, the Roman bowl made of a copper alloy was found in 2016 on a farm in Kent (United Kingdom). The team of scientists knew that it was a location that had been used for agriculture since at least 1936, so they analyzed the object's green and brown corrosion to identify its different components.
Thus, the authors found traces of chlorobenzenes in the green-colored corrosion. In addition, they also located diethyltoluamide (DEET) in brown corrosion, a modern compound that is still used in insect repellents.
The authors conclude that although chlorobenzenes are no longer used in the UK, the soil remains contaminated and may threaten the conservation of archaeological material still buried. Therefore, more research is needed to better understand the processes involved in the corrosion of archaeological remains.
