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Despite the health risks associated with exposure to Cryptosporidium and Giardia, there is no uniform approach to monitoring these protozoan parasites across the world. In the present study, a strategy for monitoring Cryptosporidium and Giardia in drinking water was developed in an effort to ensure that the risk of exposure to these organisms and the risks of non-compliance to guidelines are reduced. The methodology developed will be applicable to all water supply systems irrespective of size and complexity of the purification works. It is based on monitoring procedures proposed by the US Environmental Protection Agency, the Drinking Water Inspectorate, Australia and New Zealand, as well as the risk-based procedure followed by Northern Ireland. The monitoring strategy developed represents a preventative approach for proactively monitoring Cryptosporidium and Giardia species in drinking water. The strategy consists of 10 steps: (i) assessment of the monitoring requirements, (ii) description and characterisation of the source water types, (iii) abstraction of source water, (iv) assessment of the water purification plant, (v) water quality monitoring, (vi) cryptosporidiosis and giardiasis outbreak, (vii) risk assessment, (viii) sample collection and laboratory processing, (ix) data evaluation, interpretation and storage, (x) process evaluation and review. Proper implementation of this protocol can contribute to the protection of drinking water consumers by identifying high-risk source water, identifying areas of improvement within the water treatment system, and also preventing further faecal pollution in the catchments. The protocol can also be integrated into the Water Safety Plans to optimise compliance. Furthermore, this methodology has a potential to contribute to Blue Drop certification as it should form part of the incident management protocols which are a requirement of Water Safety Plan implementation. [ABSTRACT FROM AUTHOR]

Eighty largemouth yellowfish, Labeobarhus kimherleyensis, were collected between April 2005 and February 2006 with gill nets close to the island (26° 52, 249‱ S, 28° 10, 249‱ E) in the Vaal Dam. The fish were killed, weighed and their length determined. Muscle, liver and spinal cord tissues were collected from each fish and the intestines removed and opened to expose Bothriocephalus acheilognathi. The tapeworms were collected in glass bottles and frozen. Water and sediment, as well as liver, muscle and tapeworm samples were digested and thereafter metal concentrations of 23 elements (lithium, beryllium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, arsenic, selenium, molybdenum, cadmium, tin, antimony, tellurium, barium, mercury, thallium, lead and uranium) were determined with an ICP-MS. Bioconcentration of metals (selenium, mercury, and lead during autumn; copper, zinc, selenium, cadmium, antimony, thallium and mercury during winter; lithium, zinc, selenium, cadmium and antimony during spring; and zinc during summer) occurred in tapeworms. The highest mean value was recorded in sediment, followed by water, tapeworms and host tissue. A seasonal trend showed that a higher concentration of the metals had accumulated in tapeworms during winter when water levels were at their lowest. [ABSTRACT FROM AUTHOR]

Cyanobacteria are potent producers of cyanotoxins that may present a health risk to people. This is especially important in rural areas where people use untreated surface water, containing cyanobacteria, for household purposes including cooking and drinking. Water is collected from these sources mainly in plastic containers, transported home and stored during use. This study investigated the occurrence of cyanobacteria and their associated toxins in these containers as well as in the associated surface water sources. The results suggest that cyanobacteria are transferred from the water sources to the containers and then survive and possibly grow in biofilm forming inside the vessels. Their associated cyanotoxins were not found in any health-significant quantities in containers. However, the occurrence of cyanobacteria in the water used by the households collected in containers clearly indicates that it can be an important route of exposure especially if toxic cyanobacteria are present in the source water. In several cases a risk of cyano-intoxication might exist unless the households undertake preventative measures. [ABSTRACT FROM AUTHOR]