The Bioscan, 2 (1) 009-014,2007
An International Quarterly Journal of Life Sciences
web site: www.thebioscan.in 
REMOVAL OF HELMINTH PARASITIC EGGS FROM WASTE
STABILIZATION PONDS AT SHIMOGA
M. SHANTHALA, B. B. HOSETTI AND REBECCA STOTT*
P.G. Department of Applied Zoology, Biosciences Block
Kuvempu University, Shankaraghatta- 577451, Shimoga, Karnataka, India.
*Department of Civil Engineering and School of Biological Sciences, University of Portmouth, UK. E-mail: shanth79@yahoo.co.in, rebecca.stott@port.ac.uk

KEY WORDS

Sewage,
Stabilization ponds,
Helminth ova
Detention time.



Received on: 09.11.2006

Accepted on: 27.01.2007





*Corresponding
 Author

ABSTRACT

Helminth ova removal rates from waste stabilization pond effluents under tropical condition of Shimoga using both laboratory and field modal ponds was undertaken. The helminthes were removed to the tune of 100% from labortory model batch system ponds within 15 days of detection time and it was only 65% in case of laboratory model continous flow system ponds. The observation in field model ponds revealed as average 90% removal with 10 days retention time. A 100% removal can not be expected both in continous flow system laboratory model and field pond systems as these received daily fresh water load of helminth eggs through influent sewage. The helminth ova usally removed from waste stabilization ponds systems through sedimentation process. It is because the helminth eggs attached to the suspended solids and when these solids settle to the bottom, the eggs are also removed from pelagic water. In the present study egges of 4 helminth species viz. Ascaris lumbricoides, Hymenolepis diminuta, Hymenolepis nana and Enterobius vermicularis were encountered. Their rate of ova removal in batch system ponds was 99%, 97.4%, 94.9% and 98.8% for respective species. Presence of the sewage water indicates the prevalence of infection in city population.