Toxic Effect Of Dialkyl Phosphinate And Bisphenol AF On Aquatic Organisms

In recent years, organicphosphorus flame retardants(OPFRs) and Bisphenol AF(BPAF) have caused wide concern as new kinds of pollutants. Aluminium Methylcyclohexylphosphinate(AMHP) is a new type of organic phosphorus flame retardants synthesized by China. It is considered to be a good substitute for brominated flame retardants due to its excellent flame retardant performance as well as the ability of plasticizing. The AMHP as a kind of flame retardant is going out from laboratory to market now, but the research concerns its toxic effects on aquatic organisms is still rare. The results of early stage of the laboratory(the previous study) showed that BPAF could dramatically induce the Vitellogenin(VTG) expression in the liver of male zebrafish. BPAF is regarded as a kind of endocrine disrupting compounds. As a result, the zebrafish embryos and Daphnia magna were used as animal models in this article. On one hand, the study explored the toxic effects of Aluminium Methylcyclohexylphosphinate(AMHP), Calcium Methylcyclohexylphosphinate(CMHP), Aluminum Methylethylphosphinate(AMEP) and Aluminum Diethylphosphinate(ADEP) on zebrafish embryos and Daphnia magna as aquatic organisms. On the other hand, the study researched the relationship between estrogen effect and Estrogen Receptors of BPAF in zebrafish larvae.1. After zebrafish larvage exposed in different concentrations of Dialkyl Phosphinates and its metabolic products for 7 days, AMHP and CMHP did not cause the death of zebrafish larvage and abnormal of hatchability. However, high dose group(1000mg/L) of their hydrolysate could result in the death of zebrafish larvage significantly. Meanwhile, high concentration group(500mg/L) of ADEP and AMEP caused that zebrafish embryos could not hatch and then death eventually. However, the mortality rate(500mg/L) reduced obviously after removing the embryos serosa.2. The study exposed Daphnia magna in AMHP and CMHP as well as their hydrolysate for 7 days. The Daphnia magna dead abundantly on high concentration group(400 and 500mg/L) at 48 h after the exposure of AMHP. The mortality appeared on concentration of 1000mg/L at 48 h after exposure of CMHP. We thought that the order of toxicity was MHPA>AMHP>CMHP On the basis of 48h- LC50(GB/T 16125-2012). According to the calculation of the natural logarithm curve for LC50, the toxicities of AMHP and CMHP were due to their hydrolysate MHPA. Meanwhile, on account of the toxic effect of aluminium ion to Daphnia magna, the toxicity of AMHP was larger than CMHP.3. After being exposed in BPAF(0.5 mg/L and 1 mg/L)and combined exposure of E2(0.25 μM)and BPAF, the results show that: Single exposure of BPAF has little effect on VTG, ERα, and ERβ; the combined exposure of E2 and BPAF suggests as the concentration of BPAF increase, the expression of VTG is significantly suppressed, the expression of ERα and ERβ is also inhibited to some extent. VTG mainly expresses in liver and heart, but also brain. The expressions on day seven is significantly stronger than those in day five. ERα has been detected in heart, liver and brain after being exposed for five and seven days.