The use of food additives has increased enormously in modern food technology but they have adverse effects in human healthy. The aim of this study was to investigate the DNA damage of some food additives such as citric acid (CA), benzoic acid (BA), brilliant blue (BB) and sunset yellow (SY) which were investigated in human male germ cells using comet assay. The sperm cells were incubated with different concentrations of these food additives (50, 100, 200 and 500 mu g/mL) for 1 h at 32 A degrees C. The results showed for CA, BA, BB and SY a dose dependent increase in tail DNA%, tail length and tail moment in human sperm when compared to control group. When control values were compared in the studied parameters in the treatment concentrations, SY was found to exhibit the highest level of DNA damage followed by BB > BA > CA. However, none of the food additives affected the tail DNA%, tail length and tail moment at 50 and 100 mu g/mL. At 200 mu g/mL of SY, the tail DNA% and tail length of sperm were 95.80 +/- 0.28 and 42.56 +/- 4.66, for BB the values were 95.06 +/- 2.30 and 39.56 +/- 3.78, whereas for BA the values were 89.05 +/- 2.78 and 31.50 +/- 0.71, for CA the values were 88.59 +/- 6.45 and 13.59 +/- 2.74, respectively. However, only the highest concentration of the used food additives significantly affected the studied parameters of sperm DNA. The present results indicate that SY and BB are more harmful than BA and CA to human sperm in vitro.