Toxicity of chlorine and three non-oxidizing molluscicides to the invasive pest mussel Limnoperna fortunei.

CATALDO DANIEL; BOLTOVSKOY DEMETRIO; POSE MONICA

JOURNAL AMERICAN WATER WORKS ASSOCIATION

AMER WATER WORKS ASSOC

Lugar: Denver; Año: 2003 vol. 95 p. 66 - 78

0003-150X

The freshwater Asiatic mussel Limnoperna fortunei invaded the Parana-Uruguay river system in Argentina around 1990. Since then, the pest mussel has spread extensively and is now a major nuisance for many industrial and domiciliary water supply systems. This research exposed L. fortunei adults to chlorine and three nonoxidizing commercial molluscicides for varying amounts of time at concentrations between 0.25 and 100 mg/L at 15, 20, and 25°C. At 25°C, chlorine was effective at all concentrations (1-100 mg/L) yielding 100% mortalities in 11-17 days. At 15 and 20°C, only concentrations ~ 5 mg/L resulted in total kills after three to six weeks of exposure. The first molluscicide had little effect at 1 mg/L at all temperatures, but 2.5 mg/L of the molluscicide at 20 and 25°C attained 80-90% mortalities on the third day of postexposure. At 15°C, the second molluscicide failed to kill 100% of the mussels exposed at all concentrations tested. At 20°C, only doses> 10 mg/L eliminated all the mollusks, but at 25°C, all concentrations of the molluscicide down to 2.5 mg/L were 100%effective in one week or less. The third molluscicide proved to be the mosttoxic of the compounds tested, yielding > 50% mortalities at all temperatures at ~ 1 mg/L. At higher temperatures, toxicity was substantially enhanced for all toxicants, especially chlorine.