Developmental effects of TCIPP and TnBP on zebrafish (Danio rerio) embryos / 中华预防医学杂志

Objective: To investigate the toxicity of tris (2-chloropropyl) phosphate (TCIPP) and tributyl phosphate (TnBP) on the growth and development of zebrafish embryos, as well as to explore the underlying mechanisms at the transcriptional level. Methods: With zebrafish as a model, two hpf zebrafish embryos were exposed to TCIPP and TnBP (0.1, 1, 10, 100, 500, and 1 000 μmol/L) using the semi-static method, and their rates of lethality and hatchability were determined. The transcriptome changes of 120 hpf juvenile zebrafish exposed to environmentally relevant concentrations of 0.1 and 1 μmol/L were measured. Results: The 50% lethal concentrations (LC50) of TCIPP and TnBP for zebrafish embryos were 155.30 and 27.62 μmol/L (96 hpf), 156.5 and 26.05 μmol/L (120 hpf), respectively. The 72 hpf hatching rates of TCIPP (100 μmol/L) and TnBP (10 μmol/L) were (23.33±7.72)% and (91.67±2.97)%, which were significantly decreased compared with the control group (P<0.05). Transcriptome analysis showed that TnBP had more differential genes (DEGs) than TCIPP, with a dose-response relationship. These DEGs were enriched in 32 pathways in total, including those involved in oxidative stress, energy metabolism, lipid metabolism, and nuclear receptor-related pathways, using the IPA pathway analysis. Among them, three enriched pathways overlapped between TCIPP and TnBP, including TR/RXR activation and CAR/RXR activation. Additionally, DEGs were also mapped onto pathways of LXR/RXR activation and oxidative stress for TnBP exposure only. Conclusion: Both TCIPP and TnBP have growth and developmental toxicities in zebrafish embryos, with distinct biomolecular mechanisms, and TnBP has a stronger effect than TCIPP.

Verification on the Developmental Toxicity of Short-term Exposure to Phenol in Rats / 生物医学与环境科学（英文）

Objective@#To verify the health advisory for short-term exposure to phenol.@*Methods@#The method of this validation experiment was the same as the US Environmental Protection Agency (EPA) methodology for toxicology experiments used to determine phenol drinking water equivalent level (DWEL). Pregnant female Sprague-Dawley rats were administered phenol in distilled water by gavage at daily doses of 15, 30, 60, 120, and 240 mg/kg body weight (b.w.) from implantation (the 6th day post-mating) to the day prior to the scheduled caesarean section (the 20th day of pregnancy). The following information was recorded: general behavior; body weight; number of corpus luteum, live birth, fetus, stillbirth, and implantation; fetal gender; body weight; body length; tail length; and abnormalities and pathomorphological changes in the dams.@*Results@#In the 60 mg/kg b.w. dose group, the mortality of pregnant rats increased with increasing doses, suggesting maternal toxicity. Fetal and placental weights decreased as phenol dose increased from 30 mg/kg b.w., and were significantly different compared those in the vehicle control group, which suggested developmental toxicity in the fetuses. However, the phenol-exposed groups showed no significant change in other parameters compared with the vehicle control group ( > 0.05).@*Conclusion@#Despite using the same method as the US EPA, a different NOEAL of 15 mg/(kg·d) was obtained in this study.

Sub-chronic Toxicity of Defoamer Used in Seawater Desalination / 生物医学与环境科学（英文）

OBJECTIVE@#To explore the possible long-term health effects of the defoamer used in seawater desalination by sub-chronic toxicity testing.@*METHODS@#Blood analysis, internal organ assessment, and histopathological examination were carried out in rats exposed to low, medium, and high (0.5, 1.0, and 2.0 g/kg BW, respectively) doses of defoamer for 90 days through oral administration.@*RESULTS@#The high dose group showed decreased blood alanine aminotransferase and aspartate aminotransferase (P < 0.05). All doses resulted in a significant increase in albumin and decrease in globulin (P < 0.05). The direct bilirubin and indirect bilirubin were decreased in the medium and high dose groups (P < 0.05). All dose groups showed significant induction of alkaline phosphatase (P < 0.05). Pathological examination revealed a case of liver mononuclear cell infiltration in the medium dose group and three cases of liver congestion, steatosis of hepatic cells around the central vein, and punctate necrosis with multiple focal mononuclear cell infiltration in male rats administered the high dose. The No Observed Adverse Effect Level was 0.5 g/kg BW in rats, with albumin and total bilirubin as health effect indices.@*CONCLUSION@#Long-term defoamer exposure may cause liver injury but has no significant impact on renal function in rats. The effect on blood cells in female rats was more prominent than that in male rats.

Potential Effects of Desalinated Seawater on Arteriosclerosis in Rats / 生物医学与环境科学（英文）

To evaluate the potential risk of arteriosclerosis caused by desalinated seawater, Wistar rats were provided desalinated seawater over a 1-year period, and blood samples were collected at 0, 90, 180, and 360 days. Blood calcium, magnesium, and arteriosclerosis-related indicators were investigated. Female rats treated with desalinated seawater for 180 days showed lower magnesium levels than the control rats (P < 0.05). The calcium and magnesium levels in female rats and the magnesium level in male rats were lower than the levels in the controls, following treatment with desalinated seawater for 360 days (P < 0.05). Blood levels of arteriosclerosis-related lipid peroxidation indicators and C-reactive protein (CRP) in the treatment group did not differ from those in the controls. The levels of lipid peroxidation indicators and CRP in rats were not significantly affected by drinking desalinated seawater, and no increase in risk of arteriosclerosis was observed.