Comparative toxic effects of butylparaben sodium, sodium diacetate and potassium sorbate to Dunaliella tertiolecta and HL7702 cells.

Butylparaben sodium (BP), sodium diacetate (SDA) and potassium sorbate (PS) are safe and internationally recognized preservatives. The aim of this study is to further evaluate their toxicities using microalgae cells, and a comparison is made with their mammalian cell cytotoxicities. Unicellular Dunaliella tertiolecta, was employed to test the possible toxicities of BP, SDA and PS. The results show that the three preservatives have a negative effect on D. tertiolecta, as manifested by a strong decrease in chlorophyll and carotenoid content, viable algal cells, and superoxide dismutase (SOD) and catalase (CAT) activities. SDA and PS had small effects on the normal hepatocytes HL7702, but similar to that for MCF-10A cells, BP is toxic. The effective concentration (EC) value for HL7702 is 215.97 mg L. It is concluded that BP, SDA and PS have low toxicities to D. tertiolecta under slightly alkaline conditions, while under acidic conditions, SDA has moderate toxicity and PS has high toxicity. The sensitivity of algal cells is higher than that of HL7702 cells under slightly alkaline conditions, and is even more sensitive under acidic conditions. D. tertiolecta can be used as a pre-screen for toxicity testing.