Akvatická ekotoxikologie
Sedimenty
Advantages and limitations of sediment
toxicity tests
Advantages
* Provide a direct measure of benthic effects.
* Limited special equipment is required.
* Methods are rapid and inexpensive.
* Legal and scientific precedence exist for use; ASTM standards are
available.
* Tests with spiked chemicals provide data on cause-effect relationships.
* Sediment toxicity tests can be applied to all chemicals of concern:
* Tests applied to field samples reflect cumulative effects of all
contaminants and contaminant interactions. Toxicity tests are
amenable to field validation.
Modifed from Swartx R. C.: Marine sediment toxicity tests, with permission from
Contaminated Marine Sediments-Assessment and Remediation, copyright 1989 by the
National Academy of Sciences Courtesy of the National Academy Press. Washington DC.
Advantages and limitations of sediment toxicity
tests
Limitations
* Sediment collection, handling, and storage may alter bioavailability.
* Spiked sediment may not be representative of field-contaminated
sediment.
* Natural geochemical characteristics of sediment may affect the
response of test organisms.
* Indigenous animals may be present in field-collected sediments.
* Route of exposure may be uncertain and data generated in sediment
toxicity tests may be difficult to interpret if factors controlling the
bioavailability of contaminants in sediment are unknown.
* Tests applied to field samples cannot discriminate effects of individual
chemicals.
* Few comparisons have been made of methods or species.
* Only a few chronic methods for measuring sublethal effects have been
developed or extensively evaluated. Laboratory tests have inherent
limitations in predicting ecological effects.
* Tests do not directly address human health effects.
Table .7. Commonly used species for whole-sediment toxicity testing
Organism Endpoint Test duration (d) Habitat Feeding habit
Freshwater
Hyalella azteca (amphipod)° S, G, R 28 Burrow, epibenthic Deposit feeder
Diporeia sp. (amphipod)" S . 28 Burrow, infaunal Deposit feeder
Chironomus riparius (midge)" S. G, E l4 Tube dweller Suspension and deposit
Chironomus rentans (midge)" S, G 10 Tube dweller Suspension and deposit
Hexagenia limbata (mayfly)` S, G, V 10 Tube dweller Suspension and deposit
Ceriodaphnia dubia (cladoceran)S, R 7 Water column Suspension feeder
Daphnia magna (cladoceran)" S, G, R 10 Water column Suspension feeder
Lumbriculus variegatus` S, G, R 28 Burrow, infaunaU Deposit feeder
Tubifex tubifex S 28 Burrow, infaunal/epibenthic Deposit feeder
Salt water
Rhepoxymius abronius
(amphipod)r S l0 Burrow, infaunal Deposit feeder, predator
Eohaustorius estaurius
(amphipod)" S 10 Burrow, infaunal Deposit feeder
Ampeiisca ubdita (amphipod)` S, G, R 20 Tube dweller Suspension and deposit
Grundidiarela japonica
(amphipod)` S, G 10 Tube dwcller Deposit feeder
Hyalella azteca (amphipod)" S, G. R 28 Burrow, epibenthiu Deposit fceder
Leptocheirus plumurosus
(amphipod) S, G, R 28 Burrow, infaunal Deposit feeder
Neanthes sp. (polychaetey S, G, R 85 Tube dwcller Deposit feeder
Capiteffa capitata (polychaete)` S, G, R 35 Tube dweller Deposit fecdcr
Nereis virens (polychaete)' S 12 Tube dweller Dcposit feeder
Modified from Nebeker et al. (1989). (Reprinted with permission from Nebeker. A. V,
Schuytema, G. S.. Griffis, W. L.. Barbitta, J. A., Carey, L. A.: Effect of sediment organic
carbon on survival of Hyalella azteca exposed to DDT and endrin, Environmental
Toticology and Chemistry, 8(8):705-718. Copyright 1989 SETAC).
DDT LC50 concentrations and 95% confidence intervals at three
sediment total organic carbon concentrations for Hyalella azteca.
Percent Sediment
Total Organic Carbon (TOC)
Modified from Nebeker et al. (1989). (Reprinted with permission from Nebeker. A. V,
Schuytema, G. S.. Griffis, W. L.. Barbitta, J. A., Carey, L. A.: Effect of sediment organic
carbon on survival of Hyalella azteca exposed to DDT and endrin, Environmental
Toticology and Chemistry, 8(8):705-718. Copyright 1989 SETAC).
Endrin LC50 concentrations and 95% confidence intervals at three
sediment total organic carbon concentrations for Hyalella azteca.
Percent Sediment
Total Organic Carbon (TOC)
Survival of the
infaunal amphipod,
Rhepoxynius abronius
in sediment from
waterways adjacent to
Commencement Bay,
Washington.
(Reprinted from Marine
Rollulion Ruffetin 13: Swnrtz,
R. C., Deben, W A., Sercu, K.
A., Lamberson, J. O.,
Sediment toxicity and the
distribution of amphipods in
Commencement Bay,
Washington, USA, pp. 359-
364, Copyright 1982, with
permission from Pergamon
Press Ltd, Headington Hill Hall,
Oxford OX3 OBW, UK.)
Table 6. Mean survival of Rhepoxynius abronius and distribution of amphipods in
Commencemenl Bay, Washington and adjacent waterways"
Phoxocephalid
Survival All amphipods amphipods
Station
(%) S N S N
Commencement Bay Transect
Deep disposal site (DSI) 86 A 6.4 A 15.4 A 1.2 3
Transect station (DSII) 89 A 5.4 A 12.0 AB 2.4 6.2
Transect station (DSIII) 88 A 5.6 A 18.6 A 1.6 9.6
Transect station (DSIV) 89 A 2.8 AB 6.2 BC 0.8 2.2
Shallow disposal site (DSV) 86 A 2.2 B 3.0 CD 0.5 0.8
Browns Point (B) 76 B 5.0 A 11.4 AB 0 0
Hylebos Waterway (HI) 61 B 1.4 B 2.6 D 0 0
Silcum Waterway (SI) 89 A 1.2 B 1.6 D 0 0
Blah Waterway (LI) 86 A 1.4 B 1.4 D 0 0
City Waterway (CII) 71 B 0 0 0 0
Density data are mean number of individuals (N) and mean number of species (5) in the
0.1m2 grab sample. Survival of amphipods in the Yaquina Bay control was 9l%. Means
sharing a common letter in each column are not significantly different.
Modified from Swanz et al., 1992.
A sediment quality value for a given contaminant is determined by
calculating the sediment concentration of the contaminant that
corresponds to an interstitial water concentration equivalent to the
U.S. EPA water quality criterion for the contaminant.
Safe sediment concentrations of specific chemicals are established
by determining the sediment chemical concentration that results in
acceptable tissue residues.
Toxicity of interstitial water is quantified and identification
evaluation procedures are applied to identify and quantify chemical
components responsible for sediment toxicity.
Environmental degradation is measured by evaluating alterations in
benthic community structure.
Test organisms are exposed to sediments that may contain known ar
unknown quantities of potentially toxic chemicals. At the end of a
specified time period, the response of the test organisms is examined
in relation to a specified end point. Dose-response relationships can
be established by exposing test organisms to sediments that have
been spiked with known amounts of chemicals or mixtures of
chemicals.
Sediment chemical contamination, sediment toxicity, and benthic
community structure are measured on the same sediment sample.
Correspondence between sediment chemistry, toxicity, and field
effects is used to determine sediment concentrations that
discriminate conditions of minimal, uncertain, and major biological
effect.
The sediment concentration of a contaminant above which
statistically significant biological effects (e.g., sediment toxicity) are
always expected. AET values are empirically derived from paired
ticld data for sediment chemistry and a range of biological effects
indicators.
Equilibrium partitioning
Tissue residues
Interstitial water toxicity
Benthic community
structure
Whole-sediment toxicity
and sediment spiking
Sediment quality triad
Apparent effects threshold
Adaptace a oscilace
Cyklomorfózy planktonních organismů:
a ­ vířník Brachyonus calyciflorus, b ­ perloočka Daphnia
cucullata, c ­ perloočka Bosmina coregoni
Trvalá stádia vodních bezobratlých:
a ­ trvalá vajíčka vířníka, b ­ gemule houby, c ­ efipium s trvalými
vajíčky perloočky rodu Daphnia, d ­ statoblast mechovky, c encystovaná
plazivka
Vertikální cirkadianní migrace planktonních živočichů. Po setmění vyplouvají
živočichové z hlubších vrstev vody k hladině a po rozednění naopak ze
svrchních vrstev vody sestupují do hloubky. Šířka polygonů na grafu vyjadřuje
relativní četnost jedinců v různých hloubkách - vztaženo na celou populaci
planktontů N (podle Whitekera, 1975)
Velikost obsádky je vyjádřena biomasou, množství ostatních skupin abundancí:
B - bakterie, P - prvoci, P - fytoplankton, R - vířníci, C - perloočky a buchanky, CH pakomáři,
D - obsádka ryb
Sukcese v rybníku s mírně přesazenou obsádkou
ryb po jarním napuštění.
Příklady různých adaptací organismů na vliv proudění: 1 utváření listů a
řapíku Nuphar luteum, 2 přichycování k podkladu pomocí háčku na
končetinách a pošinkách (larva chrostíka), 3 silně zploštělý typ larvy
Blephanicera s břišními přísavkami, 4 přidržovácí poloha larev muchniček, 5
boční zátěže schránky larvy chrostíka Silo, 6 příčný a podélný profil těla ryb:
A lososovitá ryba z proudící vody, B vrankovitý typ těla (dno tekoucí vody), C
cejnovitý tvar těla (volná voda pomalejších toků a nádrží), podle různých
autorů
Rybí pásma a překrývání výskytu dominantních druhů ichtyofauny na
příkladu polské řeky Raba (Starmach, 1956, upraveno)
Ukázka příslušníků neustonních organismů. Epineuston: 1 Chromatophyton
rosanoffi, 2 Botrydiopsis arhiza, 3 Neustococcus emersus. Hyponeuston: 4
Lampropedia hyalina, 5 Navicula sp., 6 Codonosiga botrytis, 7 Arcelia sp. (podle
Ruttnera, 1962)