Three simple biomarkers useful in conducting water quality assessments with bivalve mollusks

While biomarkers are undeniably key tools in aquatic ecotoxicology to measure adverse effects linked to contamination events, their application is often inhibited by monetary constraints negating the possibility of having access to dedicated equipment, special wares, and/or expensive reagents. To offset this bottleneck, we propose three simple physiological biomarkers, quantifiable in bivalves, that are free of cost considerations and that can provide basic knowledge on animal health and water quality. Indeed, condition index (CI), growth index (GI), and SOS response (air-time survival) comprise measurements straightforward enough to perform by any laboratory or science body on the planet. Long-term monitoring or screening studies can be carried out with these biomarkers and they are able to provide robust information notably after exposure of bivalves to either singular or multiple agents of contamination. By highlighting examples of data generated in aquatic studies conducted in Eastern Canada under both laboratory and field situations with different species of marine and freshwater mollusks, we establish the suitability of these biomarkers for assessing environmental contamination. Their relationships with other biomarkers are also shown which further corroborate their value as reliable indicators of ecosystem health.