Municipal wastewaters are major sources of pollution for the aquatic biota. The purpose of this study was to determine the levels of some pharmaceutical products and the immunotoxic potential of a municipal wastewater...Municipal wastewaters are major sources of pollution for the aquatic biota. The purpose of this study was to determine the levels of some pharmaceutical products and the immunotoxic potential of a municipal wastewater aeration lagoon for the treatment of the domestic wastewaters of a small town with wastewater inputs from a 400-bed hospital complex. Endemic mussels were collected, caged and placed in the final aeration lagoon and at sites 1 km upstream and 1 km downstream of the effluent outfall in the receiving river for a period of 14 days. The results showed that the final aeration lagoon contained high levels of total coliforms, conductivity and low dissolved oxygen （2.9 mg/L） as well as detectable amounts of trimethoprim, carbamazepine, gemfibrozil, and norfloxacin at concentrations exceeding 50 ng/L. The lagoon effluent was indeed toxic to the mussel specimens, as evidenced by the appearance of mortality after 14 days （10% mortality）, decreased mussel weight-to-shell-length ratio and loss of hemocyte viability. The number of adhering hemocytes, phagocytic activity, total nitrite levels and arachidonic cyclooxygenase activity were significantly higher in mussels placed in the final aeration lagoon. A multivariate analysis also revealed that water pH, conductivity, total coliforms and dissolved oxygen were the endpoints most closely linked with phagocytic activity, the amount of adhering hemocytes and loss of hemocyte viability. In conclusion, exposure of mussels to treated aerated lagoon wastewater is deleterious to freshwater mussels where the immune system is compromised.展开更多
The discharge of organic waste from the petrochemical industry into the Mercier lagoons caused major groundwater contamination. The objective of this study was to determine the immunotoxic potential of three groundwat...The discharge of organic waste from the petrochemical industry into the Mercier lagoons caused major groundwater contamination. The objective of this study was to determine the immunotoxic potential of three groundwater wells at increasing distance from the incinerator dumping site （1.17, 2.74 and 5.40 km）. Rainbow Trout were exposed to increasing concentrations of water from three groundwater wells for 14 days. Immunocompetence was characterized by phagocytosis, mitogen-stimulated proliferation of lymphocytes, cell cycle analysis and apoptosis. A significant increase in innate （phagocytosis） and specific immune response （B lymphocyte proliferation） was observed in trout exposed to water collected from the well at 2.74 km. However, phagocytosis activity was suppressed in groups at 1.17 and 5.40 km. The proportion of lymphocytes in S phase was significantly increased in groups at 2.74 and 5.40 kin, while lymphocytes in G0/G1 phase were decreased in all three exposure groups. Additionally, dexamethasone （DEX）-induced apoptosis of lymphocytes was significantly reduced in the group at 2.74 km, which suggests decreased lymphocyte turnover. Furthermore, the ratio of DEX- induced apoptosis/apoptosis was lower in the groups at 2.74 and 5.40 km. In summary, our experiments have shown that exposure to the mixture of organic compounds present in Mercier groundwater modulates phagocytosis and cell proliferation, disrupts the cell cycle and reduces the ratio of DEX- induced apoptosis/apoptosis. It is concluded that groundwater collected in the vicinity of an incinerator containment field could impact immunocompetence in fish.展开更多
Municipal effluents are known to impede the immune system of aquatic organisms. The purpose of this studywas to examine the immunotoxicity of urbanwastewaters before and after 6 treatment processes from 12 cities towa...Municipal effluents are known to impede the immune system of aquatic organisms. The purpose of this studywas to examine the immunotoxicity of urbanwastewaters before and after 6 treatment processes from 12 cities toward trout leucocytes. Freshly prepared trout leucocyteswere exposed to increasing concentrations of solid phase （C18） extracts ofwastewaters for24 hr at 15°C. Immunocompetencewasdetermined by following changes in leucocyte viability and the proportion of cells able to ingest at least one （immunoactivity） and at least three （immunoefficiency） fluorescent beads. The influentswere treated by sixdifferent treatment strategies consisting of facultative aerated lagoons, activated sludge, biological aerated filter, biological nutrient removal, chemically-assisted physical treatment and trickling filter/solid contact. Water quality parameters of thewastewaters revealed that the plants effectively removed total suspended solids and reduced the chemical oxygendemand. The results revealed that the effluents＇ immunotoxic propertieswere generally more influenced by the properties of the untreatedwastewaters than by the treatment processes. About half of the incoming influentsdecreased leucocyte viabilitywhile4 treatment plantswere able to reduce toxicity. The influents readily increased phagocytosis activity for 8/12 influentswhile itwasdecreased in4/12 influents. This increasewas abolished for4/12 of the effluents using treatments involving biological and oxidative processes. In conclusion, municipal effluents have the potential to alter the immune system in fish and more researchwill be needed to improve the treatments ofwastewaters to better protect the quality of the aquatic environment.展开更多
基金funded by the research program on municipal effluents of Environment Canada
文摘Municipal wastewaters are major sources of pollution for the aquatic biota. The purpose of this study was to determine the levels of some pharmaceutical products and the immunotoxic potential of a municipal wastewater aeration lagoon for the treatment of the domestic wastewaters of a small town with wastewater inputs from a 400-bed hospital complex. Endemic mussels were collected, caged and placed in the final aeration lagoon and at sites 1 km upstream and 1 km downstream of the effluent outfall in the receiving river for a period of 14 days. The results showed that the final aeration lagoon contained high levels of total coliforms, conductivity and low dissolved oxygen （2.9 mg/L） as well as detectable amounts of trimethoprim, carbamazepine, gemfibrozil, and norfloxacin at concentrations exceeding 50 ng/L. The lagoon effluent was indeed toxic to the mussel specimens, as evidenced by the appearance of mortality after 14 days （10% mortality）, decreased mussel weight-to-shell-length ratio and loss of hemocyte viability. The number of adhering hemocytes, phagocytic activity, total nitrite levels and arachidonic cyclooxygenase activity were significantly higher in mussels placed in the final aeration lagoon. A multivariate analysis also revealed that water pH, conductivity, total coliforms and dissolved oxygen were the endpoints most closely linked with phagocytic activity, the amount of adhering hemocytes and loss of hemocyte viability. In conclusion, exposure of mussels to treated aerated lagoon wastewater is deleterious to freshwater mussels where the immune system is compromised.
基金supported by the Canada Research Chairin Environmental Immunotoxicology(Dr.M.Fournier)
文摘The discharge of organic waste from the petrochemical industry into the Mercier lagoons caused major groundwater contamination. The objective of this study was to determine the immunotoxic potential of three groundwater wells at increasing distance from the incinerator dumping site （1.17, 2.74 and 5.40 km）. Rainbow Trout were exposed to increasing concentrations of water from three groundwater wells for 14 days. Immunocompetence was characterized by phagocytosis, mitogen-stimulated proliferation of lymphocytes, cell cycle analysis and apoptosis. A significant increase in innate （phagocytosis） and specific immune response （B lymphocyte proliferation） was observed in trout exposed to water collected from the well at 2.74 km. However, phagocytosis activity was suppressed in groups at 1.17 and 5.40 km. The proportion of lymphocytes in S phase was significantly increased in groups at 2.74 and 5.40 kin, while lymphocytes in G0/G1 phase were decreased in all three exposure groups. Additionally, dexamethasone （DEX）-induced apoptosis of lymphocytes was significantly reduced in the group at 2.74 km, which suggests decreased lymphocyte turnover. Furthermore, the ratio of DEX- induced apoptosis/apoptosis was lower in the groups at 2.74 and 5.40 km. In summary, our experiments have shown that exposure to the mixture of organic compounds present in Mercier groundwater modulates phagocytosis and cell proliferation, disrupts the cell cycle and reduces the ratio of DEX- induced apoptosis/apoptosis. It is concluded that groundwater collected in the vicinity of an incinerator containment field could impact immunocompetence in fish.
文摘Municipal effluents are known to impede the immune system of aquatic organisms. The purpose of this studywas to examine the immunotoxicity of urbanwastewaters before and after 6 treatment processes from 12 cities toward trout leucocytes. Freshly prepared trout leucocyteswere exposed to increasing concentrations of solid phase （C18） extracts ofwastewaters for24 hr at 15°C. Immunocompetencewasdetermined by following changes in leucocyte viability and the proportion of cells able to ingest at least one （immunoactivity） and at least three （immunoefficiency） fluorescent beads. The influentswere treated by sixdifferent treatment strategies consisting of facultative aerated lagoons, activated sludge, biological aerated filter, biological nutrient removal, chemically-assisted physical treatment and trickling filter/solid contact. Water quality parameters of thewastewaters revealed that the plants effectively removed total suspended solids and reduced the chemical oxygendemand. The results revealed that the effluents＇ immunotoxic propertieswere generally more influenced by the properties of the untreatedwastewaters than by the treatment processes. About half of the incoming influentsdecreased leucocyte viabilitywhile4 treatment plantswere able to reduce toxicity. The influents readily increased phagocytosis activity for 8/12 influentswhile itwasdecreased in4/12 influents. This increasewas abolished for4/12 of the effluents using treatments involving biological and oxidative processes. In conclusion, municipal effluents have the potential to alter the immune system in fish and more researchwill be needed to improve the treatments ofwastewaters to better protect the quality of the aquatic environment.
