title: Toxicity of phenanthrene in freshwater sediments to the rooted submersed macrophyte, Vallisneria spiralis.
abstract: A study was conducted to determine the response of the rooted submersed macrophyte, Vallisneria spiralis to phenanthrene in freshwater sediments with initial phenanthrene concentrations from 0 to 80 mg kg(-1) dry sediment. The sensitivity of various morphological endpoints was evaluated after 90 days of exposure. The most sensitive toxicity test endpoints were those that reflected root growth. Toxicological sensitivity of the endpoints changed with the effect level selected. The toxicity threshold from a plot of the EC(10) values was 1-2 orders of magnitude lower than those calculated for the threshold from plots of the EC(25) or EC(50) values. In addition, stimulatory responses (hormesis) on root growth were observed at subtoxic concentrations of phenanthrene, and a hormetic model should thus be incorporated for ecological risk assessment.
authors.affiliation: State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, 73 East Beijing Road, Nanjing, People's Republic of China.
authors.forename: Zai S
authors.initials: ZS
authors.lastname: Yan
authors.forename: Ying
authors.initials: Y
authors.lastname: Hu
authors.forename: He L
authors.initials: HL
authors.lastname: Jiang
mesh_terms: D002681:China; D005618:Fresh Water / Q000737:chemistry; D019015:Geologic Sediments / Q000737:chemistry; D031321:Hydrocharitaceae / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology; D010616:Phenanthrenes / Q000633:toxicity*; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000502:physiology; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D010616:Phenanthrenes; D014874:Water Pollutants, Chemical; C031181:phenanthrene