Honeybees as active samplers for microplastics

Microplastics are small pieces of plastic in the 1 mm - 5 µm range that have become a critical field of study these days since their ubiquity and potential negative effects in organisms from all environmental compartments. In recent years, a multitude of different protocols and techniques have been proposed to detect, quantify and evaluate the environmental risk these materials suppose. In this study, honeybees (Apis mellifera) are presented as active samplers for microplastics. Bees are used as sentinel of the outside pollution by characterization the particles fixed in their bodies that are captured during their flights. Honeybees were collected by Danish beekeepers in different locations of Copenhagen and surrounded areas to evaluate the differences between rural and urban apiaries. We found plastic over the animals from all sampling apiaries mostly in fragment form followed by fibres. Thirteen different polymers were confirmed with FTIR technology. Polyester materials, polyethylene and polyvinyl chloride were the most common. Animals from urban apiaries showed the highest amounts of microplastics but in a comparable amount as the rural ones. This is explained due to the connectivity of the atmosphere. The different urban settlements near rural areas act as source of microplastics through wind dispersion. This research confirms that honeybees can be used as potential biosamplers for this widespread pollution and opens a new research pathway that will be important in the future.