PubMed · 2026-05-27
Researchers developed a low-cost, field-ready protocol using the water fern Azolla pinnata to detect heavy metal pollution in wastewater. By observing visible stress signs like yellowing and die-off, communities in developing countries can screen water quality without expensive lab equipment.
Azolla pinnata showed measurable decline in green cover and increased tissue death when exposed to industrial effluents over 15-20 days, directly correlating with heavy metal concentrations.
Maximum detected metal levels were cadmium at 0.01 mg/L in blackwater, lead at 0.030 mg/L in graywater, and zinc at 0.50 mg/L in industrial effluents.
Statistical clustering (PCA and HCA) successfully separated domestic wastewater from industrial effluent types, validating the protocol's ability to differentiate pollution sources.
