Abstract:
The hospital wastewater has been one of the concerned effluents so far. In Vietnam, the majority
of hospital wastewater has not well treated before released into nature. In this study, wastewater
samples were collected at the out let of a hospital and analyzed with thirteen of chemical and
biological parameters, followed with toxicity bioassay. The Daphnia magna was exposed to the
wastewater at the concentrations of 10; 30; 50% (v/v) for chronic test during 14 days. Adversely
chronic effects were observed with the end points of survivorship and reproduction. Our results
showed that most chemical and biological parameters (11/13) were within the guideline values of
Vietnam National Technical Regulation on Health Care Wastewater (QCVN
28:2010/BTNMT) for discharge into nature, except pH and Nitrate. However, the wastewater
reduced on survivorship and reproduction of the organism in chronic exposures. The dead
neonates in brood chamber of mother daphnids were observed in 30 and 50% of wastewater
exposures while the malformation of the neonate was detected in 10% of wastewater incubation.
Results of this study showed that there were potentially risks to aquatic organisms from the
hospital wastewater and a need for revision the National Technical Regulation on Health Care
Wastewater (QCVN 28:2010/BTNMT) to protect sensitive organisms in aquatic ecosystems. |
