Ability of bank filtration to remove cyanotoxins under different levels of nutrients

Harmful algal blooms represent a major environmental problem that is rapidly growing all over the world. In the present work, the effectiveness of simulated bank filtration (BF), as an economical water treatment option, to remove cyanotoxins under different levels of nutrients (nitrates and phosphates) was investigated. Vertical flow-through columns pre-acclimated with two levels of nutrients (e.g., nitrate and phosphate—10 vs. 50 mg/L) were exposed to two different levels of cyanotoxins (10 vs. 75 µg/L). Results from our study confirmed the ability of simulated BF to remove cyanotoxins. High cyanotoxins removals (>70%) were achieved regardless of the levels of nutrients and cyanotoxins. It can be recommended to guarantee enough travel time (>7 d) to enhance the removal of cyanotoxins. Among the removal mechanisms, biodegradation was the predominant removal mechanism.