Can sodium hypochlorite reduce the risk of species introductions from diapausing invertebrate eggs in non-ballasted ships?
Many transoceanic vessels enter the Great Lakes carrying residual ballast water and sediment that harbours live animals and diapausing eggs. In this study, we examine the potential for sodium hypochlorite (NaOCl) to reduce the risk of species introductions from diapausing invertebrate eggs in residual ballast sediment. We collected sediment from three transoceanic vessels and from Lake Erie and exposed them to NaOCl concentrations between 0 and 10,000 mg/L for 24 h. Hatching success was reduced by >89% in all four experiments at 1,000 mg/L relative to unexposed controls. Fewer species hatched at high than at low NaOCl concentrations. Based on an average residual ballast of 46.8 tonnes, the volume of NaOCl required to treat inbound vessels is 374 L. Impacts of NaOCl use could be minimized by neutralization of treated residuals with sodium bisulfite. Further research is needed, however, to evaluate the effect of NaOCl on ballast tank corrosion.
Gray
Derek K
DK
Great Lakes Institute for Environmental Research, University of Windsor, Windsor, Ont., Canada N9B 3P4. grayh@uwindsor.ca
Duggan
Ian C
IC
Macisaac
Hugh J
HJ
D000818:Animals; D044822:Biodiversity; D003343:Corrosion; D004202:Disinfectants / Q000009:adverse effects / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006114:Great Lakes Region; D007448:Invertebrates / Q000187:drug effects* / Q000254:growth & development; D009792:Oceans and Seas; D012767:Ships; D012973:Sodium Hypochlorite / Q000009:adverse effects / Q000494:pharmacology*; D013997:Time Factors
D004202:Disinfectants; D012973:Sodium Hypochlorite