Tests of the Ability of Five Disinfectants to Kill New Zealand Mud Snails

Abstract

We exposed New Zealand mud snails (NZMS), Potamopyrgus antipodarum, to various concentrations of four different quaternary ammonium-based disinfectants (Roccal D-Plus, Hyamine 1622, benzalkonium chloride, and Stepanquat 50 NF) and to liquid dish soap (Dawn) for 15 min. After 24 h of recovery in water, survival of the exposed snails was determined. Generally, mortality increased with increased chemical concentration. A concentration of 500 mg/L of Roccal D-Plus was required to kill all NZMS. The concentrations of Hyamine 1622, benzalkonium chloride, and Stepanquat required to kill all NZMS were 1,350, 450, and 600 mg/L, respectively. Liquid dish soap was not reliably effective at killing NZMS; survival ranged between 16% and 100% for all concentrations tested. Our results demonstrate that the quaternary ammonium compounds Roccal D-Plus, Hyamine 1622, benzalkonium chloride, and Stepanquat 50 NF can all be effectively used to disinfect hatchery equipment that has potentially come in contact with NZMS.

Keywords:

• Roccal D-Plus
• Hyamine 1622
• benzalkonium chloride
• Stepanquat
• New Zealand mud snails

Acknowledgments

We would like to thank the staff of the Loa State Fish Hatchery (UDWR) for providing access to the hatchery and assisting with these studies. This manuscript was greatly improved with comments from R. Brummett and two anonymous reviewers. Funding for this research was provided by the Federal Aid in Sport Fish Restoration program, project F-96-R, and the Utah Division of Wildlife Resources.