In this study, the toxicity of reactive dyes and dyed fabrics was investigated using spermatozoa cells in vitro. Boar semen was exposed to different concentrations of monochlorotriazinyl dyes: yellow, red and blue. The spermatozoa cells were also exposed to extracts of dyed fabrics. After 24 and 72 hours respectively, the viability of the cells was evaluated by microscopy. The mean inhibitor concentrations IC50, showing the concentration of the dye when half of the cells are dead compared to the control sample, were calculated from the viability values. After 24 hours' exposure, the IC50 value calculated for the yellow dye was 135µg/ml, and after 72 hours 60µg/ml. The IC50 value for the red dye was 124µg/ml after 24 hours, and 46µg/ml after 72 hours. The IC50 value for the blue dye after 24 hours was 127µg/ml. After 72 hours, the blue dye caused high toxicity: more than half the cells were dead. Cotton fabrics dyed using these three reactive dyestuffs were extracted by water and analysed by the spermatozoa motility inhibition test. The viability of the cells when exposed to fabric extracts was good. However, after 72 hours' exposure, the standard deviation and coefficient of variation values for cell viability of fabric extracts were large. The spermatozoa inhibition test indicated the toxicity of pure dyes, the dyed fabrics having no adverse effects. The spermatozoa test seems to be useful when screening different substances and when used in addition to other tests. The spermatozoa motility inhibition test can be used for textile material studies.