Cryptosporidium Species and Distribution In Scottish Drinking Waters – Shaping Future Policy
Bower, M. and Grzybowski, D., Scottish Government
(Free)
The introduction of the Cryptosporidium (Scottish Water) Directions 2003 required Scottish Water to
extensively sample its raw and final waters for Cryptosporidium oocysts. This has created to an
extensive dataset, and additional research projects have added to information on species and
genotypes found in Scottish drinking waters and the performance of the risk assessment component
of the Directions. With a review of the Directions in progress, this additional information is being
considered in order to shape the future regulatory approach in Scotland. Genotyping data shows that
a wide range of Cryptosporidium species and genotypes is found throughout Scotland, but individual
supplies do not show sufficient consistency for historical genotyping data to be of use to health
professionals in predicting the health risk from future positive oocyst detections. The performance of
the risk assessment in the Directions has been evaluated and improved. It is likely that
Cryptosporidium will become a parameter to be risk assessed and controlled as part of amending
regulations to the Water Supply (Water Quality)(Scotland) Regulations 2001.
KEY WORDS: Cryptosporidium, Drinking Water, Regulation, Scottish Water, Scotland