Propolisul ca bioindicator al contaminării cu microplastice în mediul ambiant din Republica Moldova

Honey bees, due to their morphological characteristics, as well as beekeeping products, are considered relevant indicators of environmental pollution with toxic substances, whether it is microplastic particles (MP) or other toxic contaminants. The objective of this study was to evaluate the potential of propolis to be used as a bioindicator of microplastic contamination in various geographical areas of the Republic of Moldova. Eight samples of raw propolis, collected by beekeepers during the period 2023– 2024, were analyzed. Microscopic examination was performed to characterize the morphological and chromatic characteristics of the detected particles. The morphological analysis revealed that the predominant forms were fibers, in five different types, and one type of fragment. The fragments were quantitatively identified in a larger number – 53%, and fibers made up 47%, presenting a high structural and chromatic diversity, compared to the fragments. To confirm the polymeric nature and determine their chemical composition, infrared absorption spectra (FTIR) were recorded. The spectra of the microplastic particles from the propolis were compared with those of the reference substance – polyethylene terephthalate (PET). It was found that all the recorded spectra of the microplastic particles from the propolis showed characteristic bands of polyethylene terephthalate (PET). Thus, the results obtained indicate that propolis can serve as an effective indicator of microplastic pollution.