bbe DaphTox II biomonitor

The bbe DaphTox II is a biomonitor, an enhanced version of the DaphTox, which gives early warning against a wide range of toxic concentrations.

The Daphnia Toximeter (DaphTox) observes daphnids, commonly known as ‘water fleas’, under the influence of constantly running sample water. Daphnia are established test organisms to indicate water quality. Based on the extended Dynamic Daphnia Test, bbe developed a sensitive method to detect hazardous compounds in water from rivers (source-water protection), plants, distribution systems and production drains to preserve human health and to monitor water. The continuous measurement allows for the early detection of such toxic substances.

Sample water (0.5 to 2 L/h) continuously runs through the measuring chamber containing the daphnia. The live images obtained using a CCD camera are evaluated online with an integrated PC to analyse changes in the behaviour of the daphnia. If the change is statistically significant, an alarm is triggered. The method of image analysis enables a series of measurement methods and plausibility tests to assess the daphnia’s behaviour using different criteria.

Measurement using digital image analysis observes: average swim speed; speed distribution; swim height; average distance; fractal dimension of paths: curviness, turns; no. of daphnia; distribution in chamber; and size of daphnia.

The relative magnitude and duration of the presences of toxic substances is also recorded by the instrument to enable further analysis.

Features include: modern housing with a 15″ touch-screen PC for good visualisation; an air-cooled peltier element eliminates the need for extra cooling water; an algae concentrate feed syringe means no nutrient solution is necessary; and fewer tubes requiring less maintenance.

This biomonitoring system features a 1-chamber system with up to 10 daphnids or other organisms with the option for a 2-chamber system with enhanced reliability. There is an easily removable daphnia chamber which prevents air bubbles and increases detection rate.

There is integrated sample treatment (microfiltration, ultrasonic cleaning and pre-heating) and the system is low maintenance. Data transfer options include LAN, modem, relays, 4-20 mA, USB and ModBus. The easy-to-use yet sophisticated software also enables easy recording and analysis.

Applications include: surface water applications such as dam monitoring, waterway analysis and assessment and general environmental monitoring, drinking water applications like intake assessment, and research applications such as risk analysis, limnological work and research and education.