RESUMEN
Formalin is an important maternal used as a fixative agent in the dissecting rooms of the medical schools and research institutes sterilizing agent to the patient rooms in the hospitals, and adhesive material in plastic manufactures. Formalin is highly volatile chemical material and potentially occupational exposed to its vapors are anatomists, histologists, pathologist, biologist, surgeons and medical students. The majority of the studies on the formalin vapors were done devoted to the effect of formalin on the respiratory system but little attention to the effect of the formalin vapors on the lacrimal gland. This study was performed to investigate the structural alteration of the lacrimal gland under effect of formalin vapors. Twenty adult male albino rats, each average weight [200 gms], they aged about one year old were used in this study and the lacrimal gland ultrastructure were evaluated after three months of formalin vapors exposure. The structure of the lacrimal gland was affected by formalin vapors where the lacrimal acini became irregular in shape with wide irregular lumen and reduction of the secretory vesicles with irregularity in its surface and some of them were ruptured. The nucleus of the lacrimal cells has dark chromatin with irregular nuclear envelop and degenerative areas in the cytoplasm associated with lymphocytes infiltration. The mitochondrial degeneration were apparent and the smooth endoplasmic reticulum were contained variable size vacuoles