Potential of acoustic wave microsensors for aquatic ecotoxicity assessment based on microalgae

Aquatic toxicity assessments based on inhibition of algal growth have been performed, as described in the French standardized procedure T90-304. The cellular growth was monitored by acoustic micro-sensors (quartz thickness shear mode) instead of the usual optical techniques. These experiments have shown that the real component of the interfacial acoustic impedance, measured by the sensor, displayed a large linear variation along the 3-day algal growth. The acoustic technique appears to have an interesting potential for conducting automatic algal bioassays.