Mediterranean countries are the leading producers and exporters of olive oil in the world, with Italy and Spain alone consuming about 1 million tons annually. Because of the prevalence of oils exported from these countries and their high levels of consumption within their own borders, scientists from the University of Bologna and the Foundation for the Promotion of Health and Biomedical Research of the Valencian Community in Spain conducted sampling and analysis of common vegetable oils from Italy and Spain, packaged in both glass and plastic bottles, to determine the presence of microplastics.

The researchers found microplastics in every sample tested, regardless of packaging.

Samples included extra-virgin olive oil, olive oil, sunflower oil, and mixed seed oil. Most of the microplastics detected in the samples were smaller than 100 microns. Plastics often used in packaging, polyethylene and polypropylene, comprised 50.3 percent and 28.7 percent of the microplastics detected, respectively. Moreover, there was not a significant difference between the prevalence of microplastics packaged in glass and plastic.