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 exam...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.展开更多
Globally, the generation of produced water keeps increasing due to depleting wells and about 40% of this wastewater is disposed of into the environment. Produced water is made up of several components that are toxic i...Globally, the generation of produced water keeps increasing due to depleting wells and about 40% of this wastewater is disposed of into the environment. Produced water is made up of several components that are toxic in nature, like production chemicals that are used for oil and gas production activities. Oxygen scavenger and defoamer are commonly used for corrosion prevention as both are applied at different stages of corrosion prevention. Evaluation of the possible synergistic toxicity contribution of oxygen scavenger and defoamer formed the basis of this research and was conducted using the <i>Tilapia guineensis</i> as bio-indicator. The toxicity test was carried out using the ELIMINOX (oxygen scavenger) and EC9017A (defoamer) individually and both chemicals were combined together. The choice of these chemicals was premised on previous researches that have confirmed that they are toxic individually, without further research on how they interact when they are combined. These chemicals and freshwater were used to generate produced water samples in the laboratory. The experiment was set up by adding ten fishes into each of the glass containers, containing the produced water samples at different concentrations and a control sample without the chemicals. The rate of mortality of the fish for the individual chemicals ranged from 100% to 10% for the different percentage concentrations. While on the other hand, a combination of the two chemicals had more survival than mortality, the percentage survival rate ranged from 100% to 90% across all the percentage concentrations. The lethal concentration also showed that the oxygen scavenger was more toxic than the defoamer, however, when they were combined;they showed an antagonistic relationship as the toxicity of the oxygen scavenger drastically reduced. The research findings intend to create awareness of the possible interaction of production chemicals when they are used for oil and gas activities and their combined toxicity contribution to produced water. This will in turn aid government regulators in their decision-making for disposal of produced water.展开更多
基金supported by the Scientific Research Project on Marine Public Welfare Industry [No.201505021] of National Oceanic Administration’s in China
文摘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.
文摘Globally, the generation of produced water keeps increasing due to depleting wells and about 40% of this wastewater is disposed of into the environment. Produced water is made up of several components that are toxic in nature, like production chemicals that are used for oil and gas production activities. Oxygen scavenger and defoamer are commonly used for corrosion prevention as both are applied at different stages of corrosion prevention. Evaluation of the possible synergistic toxicity contribution of oxygen scavenger and defoamer formed the basis of this research and was conducted using the <i>Tilapia guineensis</i> as bio-indicator. The toxicity test was carried out using the ELIMINOX (oxygen scavenger) and EC9017A (defoamer) individually and both chemicals were combined together. The choice of these chemicals was premised on previous researches that have confirmed that they are toxic individually, without further research on how they interact when they are combined. These chemicals and freshwater were used to generate produced water samples in the laboratory. The experiment was set up by adding ten fishes into each of the glass containers, containing the produced water samples at different concentrations and a control sample without the chemicals. The rate of mortality of the fish for the individual chemicals ranged from 100% to 10% for the different percentage concentrations. While on the other hand, a combination of the two chemicals had more survival than mortality, the percentage survival rate ranged from 100% to 90% across all the percentage concentrations. The lethal concentration also showed that the oxygen scavenger was more toxic than the defoamer, however, when they were combined;they showed an antagonistic relationship as the toxicity of the oxygen scavenger drastically reduced. The research findings intend to create awareness of the possible interaction of production chemicals when they are used for oil and gas activities and their combined toxicity contribution to produced water. This will in turn aid government regulators in their decision-making for disposal of produced water.
