Comparative Toxicity of Chlorinated Saline and Freshwater Wastewater Effluents to Marine Organisms.
Toilet flushing with seawater results in saline wastewater, which may contain approximately 33-50% seawater. Halogenated disinfection byproducts (DBPs), especially brominated and iodinated DBPs, have recently been found in chlorinated saline wastewater effluents. With the occurrence of brominated and iodinated DBPs, the adverse effects of chlorinated saline wastewater effluents to marine ecology have been uncertain. By evaluating the developmental effects in the marine polychaete Platynereis dumerilii directly exposed to chlorinated saline/freshwater wastewater effluents, we found surprisingly that chlorinated saline wastewater effluents were less toxic than a chlorinated freshwater wastewater effluent. This was also witnessed by the marine alga Tetraselmis marina. The toxicity of a chlorinated wastewater effluent to the marine species was dominated by its relatively low salinity compared to the salinity in seawater. The organic matter content in a chlorinated wastewater effluent might be partially responsible for the toxicity. The adverse effects of halogenated DBPs on the marine species were observed pronouncedly only in the "concentrated" chlorinated wastewater effluents. pH and ammonia content in a wastewater effluent caused no adverse effects on the marine species. The results suggest that using seawater to replace freshwater for toilet flushing might mitigate the "direct" acute detrimental effect of wastewater to the marine organisms.
Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology , Clear Water Bay, Hong Kong, China.|College of Chemistry and Environmental Engineering, Shenzhen University , Shenzhen 518060, China.
Mengting
M
Yang
Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology , Clear Water Bay, Hong Kong, China.
Jiaqi
J
Liu
Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology , Clear Water Bay, Hong Kong, China.
Xiangru
X
Zhang
Department of Chemistry and Biochemistry, University of South Carolina , Columbia, South Carolina 29208, United States.
Susan D
SD
Richardson
D000818:Animals; D059001:Aquatic Organisms / Q000187:drug effects*; D000460:Chlorophyta / Q000187:drug effects; D004202:Disinfectants / Q000737:chemistry / Q000633:toxicity*; D004203:Disinfection / Q000379:methods; D054750:Ecotoxicology / Q000379:methods*; D005618:Fresh Water / Q000737:chemistry; D054879:Halogenation; D007455:Iodine / Q000737:chemistry; D011077:Polychaeta / Q000187:drug effects; D012623:Seawater / Q000737:chemistry; D018675:Toxicity Tests / Q000379:methods; D062065:Wastewater / Q000737:chemistry / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000633:toxicity
D004202:Disinfectants; D007455:Iodine; D062065:Wastewater; D014874:Water Pollutants, Chemical