Sub-chronic Toxicity of Defoamer Used in Seawater Desalination.

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.

Effect of Spumol K on cell wall of Aspergillus niger strains characterized by different tolerance to toxic compounds of beet molasses.

Cell walls in the mycelium of Aspergillus niger strains sensitive or resistant to toxic molasses compounds growing in the presence of Spumol K were the object of the present studies. Although the inhibitory effect of Spumol K on the cell wall was noticed in studied mycelia the sensitive strains reacted more strongly. In sensitive strains in Spumol K presence lower content of cell wall was accomplished by higher amount of proteins but lower of lipids as well as structural polymers i.e. of glucans and chitin in this wall. A weaker synthesis of chitin and lower level of cell wall enzymes, especially chitinase, were observed in these strains. The described changes seem to be responsible for the growth inhibition and mycelium sinking in sensitive strains of A. niger.