Abstract：Phaeodactylum tricomutum was selected as target organism to study the toxicity of naphthalene under various concentration. From 0h to 168h, the optical absorbance, xanthophyll and carotene content had no obvious difference with blank control in low-concentration groups of naphthalene (0.048~2mg/L). However, when the concentration of naphthalene reached 8mg/L or more, dramatically decreases of the optical absorbance, xanthophyll and carotene content were gained. Activities of superoxide dismutase(SOD) increased at first and then decreased remarkably with the increasing concentration of naphthalene, showed as “Bell Shaped Curve”. And the content of malondialdehyde(MDA) decreased slightly and then flared up and lipid peroxidant aggregated with the increasing concentration of naphthalene.
