Microscopic investigation of pollen attachment on different fabric types: Implications for forensic and allergy research

Pollen grains, in addition to their allergenic properties, play an important role in the temporal and spatial analysis of forensic events and are considered secondary trace evidence. Pollen analysis requires expertise in microscopy techniques and palynology. This study aims to determine the persistence of pollen on common used fabric types and how much of it can be removed through washing. The structural properties of the tested pollen grains and fabrics were analyzed using light microscopy (LM) and scanning electron microscopy (SEM). Additionally, the study aims to provide data to help individuals sensitive to allergenic pollens in selecting suitable fabrics. Pollen grains from Ambrosia artemisiifolia, Chenopodium album, Corylus avellana, Parietaria officinalis, and Platanus × acerifolia, which had not been tested in previous studies, were examined on five different fabric types commonly used in the textile industry: denim, artificial leather, lacoste cotton fabric, linen, and printed cotton fabric. It was determined that pollen adhesion capacity and persistence varied based on the fabric's structure and first wash was the most effective for removing pollen from fabrics. Removal of pollen grains through washing from linen, printed cotton fabric, and lacoste cotton fabric were found to be easier from denim and artificial leather. The study revealed that pollen could still be detected on fabrics even after six washes. This finding highlights the potential use of pollen grains as valuable trace evidence in forensic cases.