title: The difference between temperate and tropical saltwater species' acute sensitivity to chemicals is relatively small.
abstract: Due to a lack of saltwater toxicity data in tropical regions, toxicity data generated from temperate or cold water species endemic to North America and Europe are often adopted to derive water quality guidelines (WQG) for protecting tropical saltwater species. If chemical toxicity to most saltwater organisms increases with water temperature, the use of temperate species data and associated WQG may result in under-protection to tropical species. Given the differences in species composition and environmental attributes between tropical and temperate saltwater ecosystems, there are conceivable uncertainties in such 'temperate-to-tropic' extrapolations. This study aims to compare temperate and tropical saltwater species' acute sensitivity to 11 chemicals through a comprehensive meta-analysis, by comparing species sensitivity distributions (SSDs) between the two groups. A 10 percentile hazardous concentration (HC10) is derived from each SSD, and then a temperate-to-tropic HC10 ratio is computed for each chemical. Our results demonstrate that temperate and tropical saltwater species display significantly different sensitivity towards all test chemicals except cadmium, although such differences are small with the HC10 ratios ranging from 0.094 (un-ionised ammonia) to 2.190 (pentachlorophenol) only. Temperate species are more sensitive to un-ionised ammonia, chromium, lead, nickel and tributyltin, whereas tropical species are more sensitive to copper, mercury, zinc, phenol and pentachlorophenol. Through comparison of a limited number of taxon-specific SSDs, we observe that there is a general decline in chemical sensitivity from algae to crustaceans, molluscs and then fishes. Following a statistical analysis of the results, we recommend an extrapolation factor of two for deriving tropical WQG from temperate information.
authors.affiliation: The Swire Institute of Marine Science and School of Biological Sciences, the University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Applied Biology and Chemical Technology, the Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
authors.forename: Kevin W H
authors.initials: KW
authors.lastname: Kwok
authors.affiliation: Department of Statistics and Actuarial Science, the University of Hong Kong, Pokfulam, Hong Kong, China.
authors.forename: Gilbert C S
authors.initials: GC
authors.lastname: Lui
authors.affiliation: The Swire Institute of Marine Science and School of Biological Sciences, the University of Hong Kong, Pokfulam, Hong Kong, China; Key Laboratory of Tropical Marine Bio-resources and Ecology, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China.
authors.forename: Guang-Jie
authors.initials: GJ
authors.lastname: Zhou
authors.affiliation: National Research Laboratory of Marine Molecular and Environmental Bioscience, Department of Chemistry, the Research Institute of Natural Sciences, College of Natural Sciences, Hanyang University, Seoul 133-791, Republic of Korea.
authors.forename: Jae-Seong
authors.initials: JS
authors.lastname: Lee
authors.affiliation: State Key Laboratory in Marine Pollution, Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China.
authors.forename: Michael H W
authors.initials: MH
authors.lastname: Lam
authors.affiliation: The Swire Institute of Marine Science and School of Biological Sciences, the University of Hong Kong, Pokfulam, Hong Kong, China. Electronic address: kmyleung@hku.hk.
authors.forename: Kenneth M Y
authors.initials: KM
authors.lastname: Leung
mesh_terms: D000641:Ammonia / Q000633:toxicity; D000818:Animals; D002980:Climate; D005399:Fishes; D006863:Hydrogen-Ion Concentration; D007448:Invertebrates; D019216:Metals, Heavy / Q000633:toxicity; D010416:Pentachlorophenol / Q000633:toxicity; D019800:Phenol / Q000633:toxicity; D010944:Plants; D054712:Salinity; D012623:Seawater / Q000737:chemistry; D013045:Species Specificity; D014220:Trialkyltin Compounds / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D019216:Metals, Heavy; D014220:Trialkyltin Compounds; D014874:Water Pollutants, Chemical; D019800:Phenol; C011559:tributyltin; D000641:Ammonia; D010416:Pentachlorophenol
keywords: Environmental risk assessment; Saltwater ecosystems; Species sensitivity distributions (SSDs); Taxon-specific SSDs; Water quality guidelines