2.4 Conclusion
The quality of surface waters was monitored alongside the Seine River over
2010–2012 using in vitro bioassays of oestrogenicity applied on sediment and
water matrix contamination. The results highlighted a contamination gradient by
bioactive chemicals, increasing from upstream (Marnay-sur-Seine) to downstream
(Bougival and Triel-sur-Seine). In addition, a lower oestrogenic potential of both
water and sediment contamination was observed under high-flow conditions (winter)
compared to low-flow periods (summer). The in vitro bioassay implemented
revealed an acceptable quality of the Seine River upstream of Paris but a degraded
quality downstream of Paris according to the provisional trigger values for endocrine
disruptor contamination of the water column. These data are overall in accordance
with those from other bioassays of ED or toxic potential measurements on sediment
or water matrices collected in the same three pilot sites in the PIREN-Seine
programme [20]: bioassays measuring thyroidicity (PC-DR-LUC cells), antiandrogenicity (MDA-kb2 cells), embryotoxicity/teratogenicity on fish (Medaka
embryo-larval assay), cytotoxicity (Microtox
® assay) and genotoxicity (SOS
chromotest). In conclusion, in vitro bioassays stood out as being suitable tools to
monitor the quality of the Seine River. In addition, sediment may be considered as a
suitable matrix to monitor aquatic pollution using a bioassay-based approach, since
it is able to concentrate bioactive aquatic pollutants of a wide range of polarities and
especially to act as an integrative adsorbent matrix of the ongoing environmental
contamination by anthropic chemicals.
3 Biomarkers for the In Situ Biomonitoring of Water
Contamination
3.1 Presentation of Sentinel Species and Their Advantages
in Ecotoxicological Studies
To highlight the water contamination status, it seems wise to develop indicators
integrating the daily spatial and temporal variability of contaminant concentrations
in surface waters. Besides direct in situ measurements, the integration of contamination in wild organisms could contribute further information on environmental
hazard [22]. Moreover, since the exposure, biotransformation and effects pathways
of contaminants may differ between vertebrates and invertebrates; biomarkers need
to be studied in diverse taxa for an ecological relevance.
Biomonitoring of wild fish provides a spatially and temporally integrated view of
pollutant exposure and ecotoxicological effects, because of their relatively high
mobility, long life span (bioaccumulation over time [23]), high trophic levels
(i.e. biomagnification [24]) and slow genetic adaptation due to a slow turn over
[25]. The European chub (Squalius cephalus L.) is extensively used as a bioindicator
250
M. Bonnard et al.
The quality of surface waters was monitored alongside the Seine River over
2010–2012 using in vitro bioassays of oestrogenicity applied on sediment and
water matrix contamination. The results highlighted a contamination gradient by
bioactive chemicals, increasing from upstream (Marnay-sur-Seine) to downstream
(Bougival and Triel-sur-Seine). In addition, a lower oestrogenic potential of both
water and sediment contamination was observed under high-flow conditions (winter)
compared to low-flow periods (summer). The in vitro bioassay implemented
revealed an acceptable quality of the Seine River upstream of Paris but a degraded
quality downstream of Paris according to the provisional trigger values for endocrine
disruptor contamination of the water column. These data are overall in accordance
with those from other bioassays of ED or toxic potential measurements on sediment
or water matrices collected in the same three pilot sites in the PIREN-Seine
programme [20]: bioassays measuring thyroidicity (PC-DR-LUC cells), antiandrogenicity (MDA-kb2 cells), embryotoxicity/teratogenicity on fish (Medaka
embryo-larval assay), cytotoxicity (Microtox
® assay) and genotoxicity (SOS
chromotest). In conclusion, in vitro bioassays stood out as being suitable tools to
monitor the quality of the Seine River. In addition, sediment may be considered as a
suitable matrix to monitor aquatic pollution using a bioassay-based approach, since
it is able to concentrate bioactive aquatic pollutants of a wide range of polarities and
especially to act as an integrative adsorbent matrix of the ongoing environmental
contamination by anthropic chemicals.
3 Biomarkers for the In Situ Biomonitoring of Water
Contamination
3.1 Presentation of Sentinel Species and Their Advantages
in Ecotoxicological Studies
To highlight the water contamination status, it seems wise to develop indicators
integrating the daily spatial and temporal variability of contaminant concentrations
in surface waters. Besides direct in situ measurements, the integration of contamination in wild organisms could contribute further information on environmental
hazard [22]. Moreover, since the exposure, biotransformation and effects pathways
of contaminants may differ between vertebrates and invertebrates; biomarkers need
to be studied in diverse taxa for an ecological relevance.
Biomonitoring of wild fish provides a spatially and temporally integrated view of
pollutant exposure and ecotoxicological effects, because of their relatively high
mobility, long life span (bioaccumulation over time [23]), high trophic levels
(i.e. biomagnification [24]) and slow genetic adaptation due to a slow turn over
[25]. The European chub (Squalius cephalus L.) is extensively used as a bioindicator
250
M. Bonnard et al.