Evaluation of Multixenobiotic Resistance in Dreissenid Mussels as a Screening Tool for Toxicity in Freshwater Sediments

• Published in: Archives of environmental contamination and toxicology Vol. 68; no. 4; pp. 707 - 717
• Main Authors: Ács, A., Imre, K., Kiss, Gy, Csaba, J., Győri, J., Vehovszky, Á., Farkas, A.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01-05-2015; Springer Nature B.V
• Subjects: Abiotic stress; Acute toxicity; Adaptation, Physiological; Animals; Anthropogenic factors; Aquatic organisms; Aromatic compounds; Bioassays; Bioavailability; Biomarkers; Biomarkers - metabolism; Biota; Contaminants; Contaminated sediments; Contamination; Correlation; Daphnia magna; Defense mechanisms; Dreissena - physiology; Dreissena polymorpha; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental Monitoring - methods; Environmental stress; Environmental testing; Exposure; Fresh Water; Freshwaters; Geologic Sediments - chemistry; Laboratories; Laboratory tests; Metals; Mollusks; Monitoring/Environmental Analysis; Mussels; Pollution; Polyethylene; Sediment load; Sediment pollution; Sediments; Shellfish; Soil Science & Conservation; Soil testing; Studies; Toxicity; Water Pollutants, Chemical - toxicity; Xenobiotics - toxicity; Hungary; Freshwater Sediment; PAHs; Hatching Success; Harbor Sediment; Test Sediment
• ISSN: 0090-4341; 1432-0703
• DOI: 10.1007/s00244-015-0150-y

The multixenobiotic defense mechanism (MXR) in aquatic organisms was recognized as a first-line defense system, and its potential use as an early biomarker of exposure to environmental stress has raised attention in the last two decades. To evaluate the relevance of this biomarker in the freshwater mussel
Dreissena polymorpha
, we studied its responsiveness within laboratory exposures to contaminants sequestered in freshwater sediments affected by moderate anthropogenic impact. The effectiveness of this biomarker was assessed by comparing the MXR-transporter activities determined in bivalves first with toxicity scores recorded with the
D. rerio
embryo developmental assay. Both bioassays were applied in the sediment contact test format. As a second evaluation approach, MXR activities determined in exposed mussels were compared with sediment-contamination data integrated into toxic units on the basis of acute toxicity to
Daphnia magna
. In
D. polymorpha
subjected to acute exposure with moderately polluted sediments, we detected limited (22–33 %) but statistically significant induction of MXR activity. Mean MXR activities significantly correlated with TU values computed for test sediments. MXR activities in mussels showed strong positive correlation with the metal load of sediments and proved to be unrelated to the contamination with polycyclic aromatic compounds. MXR activity in laboratory-exposed mussels showed low variability within treatments and thus reliably reflected even low contaminant differences between the negative reference and moderately polluted harbor sediments. The strong correlation found in this study between the MXR-transporter activity in exposed mussels and environmentally realistic sediment contamination underscores the fairly good sensitivity of this biomarker in laboratory testing conditions to signal the bioavailability of sediment bound contaminants, and it may also anticipate even the incidence of toxicity to biota.