Recent research have found microplastics in ancient soil samples, undermining the idea that archeological deposits were clean. Microplastics, defined as plastic bits less than five millimeters, have been found in soil strata from the first or second century CE and sediment cores from urban estuaries and freshwater lakes.
York University researchers identified microplastics in soil deposits more than seven meters deep from the first or second century CE and excavated in the 1980s. This shows that microplastic pollution has been in the soil for a long period. In contemporaneous and historical soil samples, 16 microplastic polymer types were found, suggesting the extent of this pollution.
Microplastics in archaeological soil samples affect archaeology. Microplastics change soil chemistry, which accelerates organic material degradation and reduces archeological remains’ scientific value. This casts doubt on in-situ preservation and may require a rethinking of historical site preservation.
The studies also show that plastic contamination has penetrated even the oldest layers. This new reality may require archaeologists to rethink how they preserve and analyze ancient relics. The University of York and Hull study team, backed by York Archaeology, calls for more microplastic research on archaeological sites.
Microplastics have been detected in marine and freshwater sediment cores and archaeological sites. Microplastics are abundant in sediments, especially in smaller size classes, according to studies. Microplastic distribution and abundance in sediment cores are linked to plastic manufacture, coastal population increase, and urban water outflows.
The presence of microplastics in ancient soil samples and sediment cores shows the widespread impact of plastic contamination. To stop microplastics from destroying our environment and history, it requires a worldwide response.