The ISO-30500 standard, published in 2018, looks at the general safety and performance requirements for the design and testing of sustainable non-sewered sanitation systems (NSSS). The standard aims to ensure quality of these NSSS to support their production at scale, thereby enabling faster entry into the sanitation market. While the standard was successfully published in 2018, no NSSS have yet been certified. The main reason is that the certification process requires an established infrastructure and certification capacity by national certification bodies. To address this, the standards agency TüV SüD has undertaken the task to support the development of certification capacity in specific countries, including South Africa. TüV SüD requires that new sanitation technology developers have their systems accredited to the ISO-30500 standard and for this they require large numbers of Ascaris suum eggs. [Ascaris suum eggs from the pig roundworm are widely used as a surrogate for A. lumbricoides, the human roundworm.] TüV SüD have communicated to the Centre that Excelsior Sentinel in the USA, the previous sole supplier of A. suum eggs, cannot meet the demand.

The Centre’s Helminth Method (for processing and recovery of helminth eggs and larvae that can subsequently be microscopically differentiated by genus, enumerated, and a viability assessment performed) was developed by a past student (David Hawksworth) and Dr Archer, and subsequently improved by Dr Archer. It is regularly used in parts of South Africa, India, Africa and at IHE Delft. However, it does not yet have international recognition. A current project (2019-2021) funded by the Water Research Commission (WRC) aims to provide a detailed interrogation of the Centre’s Helminth Method to establish it as an alternative for testing non-sewered sanitation excreta, and environmental samples like soil. This method has ensured that the procedure is adapted to the sample type, unlike the USEPA method (developed specifically for testing water and wastewater samples) that requires adapting the sample to suit the method, i.e., by adding a wash solution to ‘liquidize’ the sample, with associated overnight settling times. Miss Danica Naidoo is doing this work for her PhD and the final method will be rigorously tested for recovery and reproducibility, two important steps for accreditation of a method. The intention is to publish the final product in a methods journal of high standing, e.g., Nature Methods. The MSc graduate employed as the Ascaris-Pig-Farm egg harvester is also working on finding a suitable vital stain for use on Ascaris eggs that, when spiked into toilet systems (for research projects as well as for ISO accreditation), can be differentiated from Ascaris eggs excreted into toilets by users. By keeping the Ascaris-Pig-Farm operational, the Centre will be able to complete these two important projects as it will enable a continuous supply of eggs for further research.