Determinar la toxicitat dels sediments en els ecosistemes aquàtics és un repte, i és necessari per a una adequada avaluació del risc toxicològic en aquests ecosistemes. En les darreres dècades s’han estudiat i aplicat diferents eines (ex. tests de laboratori amb diferents concentracions, tests amb l’aigua intersticial, estudis de bioacumulació, índexs de toxicitat). Actualment es recomana l'aplicació conjunta d'eines químiques, ecològiques i toxicològiques per a una adequada avaluació. En aquest treball utilitzem l’aproximació de les Toxic Units, tests de toxicitat amb l’aigua intersticial (Vibrio fischeri, Pseudokirchneriella subcapitata i Daphnia magna) i tests d'exposició amb el sediment (V. fischeri, Chironomus riparius), juntament amb l’estudi de la comunitat d'invertebrats, per detectar respostes a curt i llarg termini en quatre rius de la Península Ibèrica: el Llobregat, l’Ebre, el Xúquer i el Guadalquivir. by Núria de Castro-Català, Maja Kuzmanovic, Neus Roig, Jordi Sierra, Antoni Ginebreda, Damià Barceló, Sandra Pérez, Mira Petrovic, Yolanda Picó, Marta Schumacher and Isabel Muñoz

1. Ecotoxicity of river sediments:
invertebrate community, toxicity
bioassays and the Toxic Unit approach as
complementary assessment tools
Núria de Castro-Català, Maja Kuzmanovic, Neus Roig, Jordi Sierra, Antoni Ginebreda, Damià
Barceló, Sandra Pérez, Mira Petrovic, Yolanda Picó, Marta Schumacher and Isabel Muñoz

2. INTRODUCTION
 Sediment quality is crucial to the health of an aquatic
ecosystem.
 Efficient extraction technologies and liquid chromatography
mass spectrometry (LC-MS)
Picó et al. 2015 Anal Bioanal Chem

3. INTRODUCTION
 Chemical concentrations alone are insufficient to
demonstrate adverse environmental effects because they
do not provide evidence of toxicity
 Bioavailability depends upon hydrological conditions,
sediment composition, organic matter content, ...
 Different modes of action, different sensitivities of the
organisms

4. OBJECTIVES Multi-stressed river basins from the Iberian Peninsula
 4 – 5 sampling sites in each River

5. OBJECTIVES
 Pollutants
Toxicity
What kind of toxicity?
 How much?

6.  Pollutants
 Organic compounds:
POPs, Pests, PhACs, EDCs, PFCs
OBJECTIVES

7. POPs (Persistent Organic Pollutants)
 PAHs (Polycyclic aromatic hydrocarbons):
- fossil fuels and in tar deposits
- result of incomplete combustion of organic matter
 PCBs (Polychlorinated biphenyls):
- used as dielectric and coolant fluids
- banned by the United States Congress in 1979 and by the
Stockholm Convention on Persistent Organic Pollutants in 2001.

8. EDCs (Endocrine Disrupting Compounds)
 Azoles corrosion inhibitors
 Bisphenol A
 Parabens
preservatives in cosmetics and pharmaceuticals
 Estrogens
 Alkylphenols detergents, fuels and lubricants,
phenolic resins, fragrances, antioxidants, oil field
chemicals and fire retardant materials
 Others…

9. PFCs (Perfluorinated compounds)
 used in textiles and food packaging due to their unique
properties as repellents of water and oils
 also used as surfactants and lubricants in fire-fighting foams,
pesticides and personal care products
©4-seasons.de ©chemicalfreelife.tumblr.com © kangahoo.com

10.  Pollutants
 Organic compounds:
POPs, Pests, PhACs, EDCs, PFCs
 Metals
Pore water and whole sediment
BCR sequential extraction, AVS and SEM
 Sediment characterization
Grain size, organic carbon and organic matter content
OBJECTIVES

11.  Toxicity risk assessment:
Toxic Units
Toxicity tests
 Whole sediment tests
 Pore water tests
Invertebrate community
OBJECTIVES

12.  Toxic units Sprague and Ramsay, 1965
MATERIALS AND METHODS

13.  Toxic units
Di Toro et al., 1991
Höss et al., 2011
CS = CPW × Kd
MATERIALS AND METHODS
Organic compounds (WS)
Metals (PW)
Concentration Addition model => ΣTUs

14. Vibrio fischeri
15min acute test
(Microtox)
Daphnia magna
48h acute test
Pseudokirchneriella
subcapitata
72h growth test
Chironomus riparius
10d chronic test
Organismcomplexity
Duration of the test
Relevance at the community level
MATERIALS AND METHODS
 Toxicity tests
© J.W. Hastings
© www.algalweb.net/
© N. Hopkins
© mblaquaculture.com

15. Vibrio fischeri
15min acute test
(Microtox)
Daphnia magna
48h acute test
Pseudokirchneriella
subcapitata
72h growth test
Organismcomplexity
Duration of the test
MATERIALS AND METHODS
PORE WATER
Chironomus riparius
10d chronic test

16. Vibrio fischeri
15min acute test
(Microtox)
Daphnia magna
48h acute test
Pseudokirchneriella
subcapitata
72h growth test
Chironomus riparius
10d chronic test
Organismcomplexity
Duration of the test
MATERIALS AND METHODS
WHOLE SEDIMENT

17. -Community composition
- Abundances
Canonical Correpondence Analyses
 Macroinvertebrate communities of the sediment
MATERIALS AND METHODS

18. RESULTS. Metalsµg/g DW
A residual
B organic matter / sulphides
C Fe Mn oxyhydroxides
D exchangeable / carbonates
US EPA benchmark

19. RESULTS. Metals
 Pore water metals above the US EPA benchmarks:
Hg 0-0.25 µg/L As 4-140 µg/L
Cu 1-60 µg/L
 SEM/AVS ratio > 1 in J4, G2, G4 and E2

20. RESULTS. Organic compounds
PAHs (e.g., chrysene, pyrene, phenanthrene)
EDCs (e.g., nonylphenol, methylparaben)

21. RESULTS. Organic compounds TUs

22. RESULTS. Organic compounds TUs
Organophosphate
insecticides

23. RESULTS. Metals TUs

24. RESULTS. Macroinvertebrate communities
CCA
12% of the total inertia
F. Chironomidae
P. Oligochaeta
Richness decreased
downstream
Polypedilum sp.
Branchiura sowerbyi
Limnodrilus hoffmeistieri

25. Short-term (15 min to 72 h)
Whole sediment Pore water
V.fischeri V.fischeri P.subcapitata D.magna
Sample EC50 EC50 EC50 EC50
(mg/l) (%vol:vol) (%vol:vol) (%vol:vol)
E1 5348 43.4 183 >100
E2 1488 47.4 229 >100
E3 1421 72.8 101 >100
E5 5087 55 121 >100
G1 814 >100 131 >100
G2 664 >100 129 >100
G3 31.1 >100 76 >100
G4 87.7 51.5 89 >100
J2 2157 70.6 66 >100
J4 5127 >100 101 >100
J5 586 >100 147 >100
J6 902 >100 172 >100
J7 3092 >100 116 >100
L3 3244 >100 227 >100
L4 11682 >100 321 >100
L5 3076 >100 28 >100
L7 1729 >100 50 >100
RESULTS. Toxicity tests

26. RESULTS. Toxicity tests
Long-term (10 days)
Whole sediment
C. riparius
Sample mortality development biomass
% HW (mm) %control DW (mg) %control
E1 50 0.56 103 0.46 98
E2 20 0.54 100 0.42 90
E3 0 0.53 97 0.24 51
E5 0 0.57 104 0.53 112
G1 10 0.55 101 0.34 73
G2 0 0.54 100 0.17* 36*
G3 0 0.55 102 0.30 63
G4 0 0.50 92 0.29 61
J2 20 0.58 107 0.90** 192**
J4 0 0.56 104 0.43 91
J5 30 0.57 105 0.50 107
J6 0 0.56 104 0.45 96
J7 10 0.56 104 0.49 104
L3 10 0.56 103 0.47 100
L4 20 0.55 102 0.28 59
L5 30 0.45 83* 0.23 49
L7 0 0.51 95 0.30 64
Dunnett’s post-hoc tests,
*p<0.05, **p<0.01

27. C. riparius
 Mortality – TUs Chlorpyrifos
 Development and biomass – TUs PhACs
V. fischeri
 Whole sediment – TUs PhACs
 Pore water – TUs metals (Ni)
Hg
RESULTS. Significant Spearman rank correlations
p<0.05

28.  Highest toxicity:
L5, E1 and J5
 Guadalquivir river
 Júcar river
DISCUSSION

29. - High toxicity of OPs insecticides
Chlorpyrifos effects at µg/L level, bioaccumulation
(Pérez et al., 2013, Masiá et al., 2015)
DISCUSSION

30. - High toxicity of OPs insecticides
Chlorpyrifos effects at µg/L level, bioaccumulation
(Pérez et al., 2013, Masiá et al., 2015)
Malathion, diazinon and chlorfenvinphos
(Rebechi et al., 2014; Schuler et al., 2005)
DISCUSSION

31. - Toxicity of metals for unicellular organims
Cu, Ni, Hg, Zn
(Lemire et al., 2013)
- Effects at the community level
POPs (PAHs), Pests
Importance of sediment dynamism
(Buendia et al., 2013)
DISCUSSION

32. CONCLUSIONS
The combination of the TUs approach, the battery of toxicity
tests and the description of the invertebrate communities
helped us to identify OPs insecticides and some metals as the
main contributors to the sediment toxicity.

33. Moltes gràcies!
Acknowledgements
This study was funded by the Spanish Ministry of Economics and Competitiveness through the project
SCARCE (Consolider-Ingenio 2010 CDS2009-00065). We are especially grateful to Laura Armendáriz
for the identification of the Oligochaeta, and to those who assisted us in the field and helped us to obtain
data, especially, Júlio C. López-Doval and Patricia Rodrigo.
© enciclopedia.cat