Paraformaldehyde, 4% in PBS + Mg + EGTA is used as a common fixative reagent for histology. It is also used to prepare pure formaldehyde.
Suenobu, T.; Isaka, Y.; Shibata, S.; Fukuzumi, S. Catalytic hydrogen production from paraformaldehyde and water using an organoiridium complex. Chem. Commun. 2015, 51, 1670-1672.
Liu, Q.; Yuan, K.; Arockiam, P. B.; Franke, R.; Doucet, H.; Jackstell, R.; Beller, M. Regioselective Pd-Catalyzed Methoxycarbonylation of Alkenes Using both Paraformaldehyde and Methanol as CO Surrogates. Angew. Chem. Int. Ed. 2015, 54 (15), 4493-4497.
Hazard Statements: H333-H315-H318-H317-H351
May be harmful if inhaled. Causes skin irritation. Causes serious eye damage. May cause an allergic skin reaction. Suspected of causing cancer.
Precautionary Statements: P201-P261-P280-P305+P351+P338-P405-P501a
Obtain special instructions before use. Avoid breathing dust/fume/gas/mist/vapours/spray. Wear protective gloves/protective clothing/eye protection/face protection. IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. Store locked up. Dispose of contents/container in accordance with local/regional/national/international regulations.