most lasers used in our labs are capable of causing eye injury to anyone who looks directly into the beam or its specular reflection. in addition, diffuse reflections of high-power laser beam can produce permanent eye dammage. laser beams can also ignite flammable materials (solvents, acetylenic compounds ...)
the equipment to run laser experiments may also introduce additional hazards: high voltage, toxic substances (laser dyes, precursors and their by products formed during experiment, gases), vacuum (implosion of glass equipment) and gasbottles (high pressure).
laser dyes are often toxic and/or carcinogenic chemicals dissolved in flammable toxic solvents. this creates a hzard for personal exposures above permissible limits. to work with dye solutions means also to produce chemical spills (and fires).
the most hazardous aspect of a laser operation is the mixing of chemicals that make up the laser dye. (source: NIH)
little is known about the toxic properties of laser dyes, except that they are often members of chemical families that contain highly toxic material. minor changes in the chemical structure of laser dyes can have major effects on their toxic properties. animal experimentation has shown that laser dyes vary greatly in toxicity and potential carcinogenicity. consequently, all dyes should be treated as hazardous chemicals.
in many instances, the solvent in which the dye is dissolved plays a major role in the hazard. practically all solvents suitable for dye solutions are flammable and toxic by inhalation and/or skin absorption.
Laser Systems. [PDF]