Response of the zooplankton community and environmental fate of perfluorooctane sulfonic acid in aquatic microcosms.
Little is known regarding perfluorooctane sulfonic acid (PFOS) toxicity to freshwater organisms. This field evaluation aims to assess the toxicological risk associated with exposure to PFOS across levels of biological organization. The analysis of variance study was conducted in replicate (n = 3) 12,000 L outdoor microcosms. Multivariate techniques were used to assess the response of zooplankton community structure and dynamics, as well as a floating macrophyte, Lemna gibba. The zooplankton community was significantly affected (p < 0.05) by the treatment regime given by the Monte Carlo permutations for all sampling times. A community-level no-observable-effect concentration ([NOEC]community) of 3.0 mg/L was determined for the 35-day study, however, longer term studies are recommended. The most sensitive taxonomic groups, Cladocera and Copepoda, were virtually eliminated in 30 mg/L treatments after 7 d. The 42-d 50% inhibition concentration (IC50) for L. gibba frond number was 19.1 mg/L and the NOEC was 0.2 mg/L. Furthermore, we investigated the persistence of PFOS over 285 d in microcosms under natural conditions. Perfluorooctane sulfonic acid concentration showed no drastic reduction in any treatment microcosm over the entire study period, confirming that this compound undergoes little degradation in aquatic systems. Presently, there appears to be little hazard to these freshwater organisms at reported environmental concentrations.
Centre for Toxicology, Department of Environmental Biology, Bovey Building, University of Guelph, Guelph, Ontario, Canada N1G 2W1. tboudreau@esg.net
Timothy M
TM
Boudreau
Christian J
CJ
Wilson
Woo Jay
WJ
Cheong
Paul K
PK
Sibley
Scott A
SA
Mabury
Derek C G
DC
Muir
Keith R
KR
Solomon
D017738:Alkanesulfonic Acids / Q000633:toxicity*; D000818:Animals; D002965:Classification; D017753:Ecosystem; D005466:Fluorocarbons / Q000633:toxicity*; D009010:Monte Carlo Method; D015999:Multivariate Analysis; D011157:Population Dynamics; D018570:Risk Assessment; D015048:Zooplankton
D017738:Alkanesulfonic Acids; D005466:Fluorocarbons; C076994:perfluorooctane sulfonic acid