Our group performed a Daphnia magna heartbeat rate test with slight modifications according to the methodology described by Villegas-Navarro (2003) and Dzialowsky et al. (2006).

Seven various chemicals were studied representing potentially environmentally problematic chemical substances. The following chemical substances were tested: nicotine (recreational products), diclophenac and paracetamol (pharmaceuticals), β-eostradiole (hormones), triclosan (antimicrobial substances), nano-titanium (nanomaterials), metachlor (pesticides) function of concentrations in the range of 0.01 µg/l–10 mg/l. Lethality and immobilisation tests were performed according to OECD 2002 Protocol.

For the heartbeat rate test developed by our team 10 test organisms were placed into each member of the dilution series of each chemical. The heartbeat rate of each Daphnia magna was measured after 10 minutes, 24 hours and 48 hours exposure time placing one test organism on a slide in a single drop of water for visualization of the heartbeat rate by a stereomicroscope. Heart rate is expressed as beats/minute (bpm). The results are interpreted compared to the control.