Precautions:

Although neoprene itself is not a skin contact sensitizer, certain neoprene adhesives contain 4% rosin (CAS No. 8050-09-7, previously known as "colophony"), which is a skin contact sensitizer under the European Union Dangerous Preparations Directive 1999/45/EC. Some people are allergic to neoprene while others can get dermatitis from thiourea, a compound used to vulcanize rubber into neoprene which can be left over after the manufacturing process.^{[citation needed]}

Lead-containing compounds, such as litharge (lead(II) oxide), are used as compounding agents to prepare finished products made of neoprene, and these can have a toxic effect on human blood, kidneys, and reproductive systems.