Determination of bisphenol A in size fractions of indoor dust from several microenvironments

The work is focused on the verification of a sieving method for the determination of the dependency of bisphenol A concentrations on size fractions of indoor dust. The dust was sampled in houses, an office, a clothing shop and a laboratory. Microscopic photography proves that the dust consisted mostly of fibers. From the seven fractions collected (2–4 mm, 1–2 mm, 250 µm – 1 mm, 125–250 µm, 63–125 µm, 45–63 µm, >45 µm), the two biggest were discarded, because they were mostly hairs, sand and bigger objects. The analysis of smaller fractions (despite one sample from the laboratory) shows that the concentration of bisphenol A was comparative. It was stated that in the case of fibers, fractioning by sieving is inappropriate, because of the fact that all fibers have an internal diameter >45 µm, but the shape of fibers and other factors make it impossible for microplastic sieving using stainless steel sieves. The non-target analysis shows the presence of both natural and synthetic compounds, like lipids, flame retardants and personal care products. It was noticed was that acetone has possibilities for the dissolution of several plastics, thereby additional amounts of bisphenol A and other plastic additives from the plastic fibers present in dust samples could be detected and quantified. Finally, it is recommended to analyze dust fractions below 1 mm and use acetone for the extraction of bisphenol A free fractions in indoor dust samples.