BACKGROUND--Previous studies have shown that ophthalmologists using blue-green argon laser may suffer subtle defects in their colour vision. A reduction in colour contrast sensitivity in the tritan colour confusion axis, an early manifestation of blue cone photoreceptor injury by the high energy photons of the laser, has been demonstrated and has prompted a reappraisal of laser safety in ophthalmology. Argon laser is also frequently used in scientific research, often at higher power output and for longer periods than is used in clinical practice. The scientists operating these lasers are at risk of developing similar phototoxic retinal injury. METHODS--The colour contrast sensitivity of 18 scientists who regularly use short wavelength argon laser was investigated. RESULTS--Eye protection was infrequently used and individuals had been subjected to between 580 and 7200 hours of cumulative laser exposure during the course of their research. CONCLUSION--The use of blue-green argon laser by the scientists investigated was not associated with a significant reduction in colour contrast sensitivity.