The use of a vermifilter containing Eisenia fetida to degrade human faeces in a continuous wet system was explored. This paper aimed to understand the formation of vermicompost within the system, the quality of the effluent produced, and the effect of different bedding matrices. Eight filters were constructed, utilising four different bedding materials: four of these systems were seeded with 400 g of worms (vermifilters) while the others served as controls. The systems were flushed with 12 L of water per day and the experiment was split into five phases, each with different feeding regimes. Between 23.7 and 24.7 kg of fresh human faecal matter was added to the vermifilters over the 360 day period. The presence of the worms was found to increase the faecal reduction to 76% on average, compared to 17% in the control systems on average. Statistically significant reductions in phosphate, chemical oxygen demand and thermotolerant coliforms were achieved in the effluent of all vermifilters. The most suitable bedding matrix was a mixture of coir and woodchip. This study shows that there is potential for continuous treatment of human faeces using wet, on-site vermifilters.

This paper describes the development of a novel onsite sanitation system based on vermifiltration, the ‘Tiger Toilet’. Initial laboratory experiments demonstrated that feed distribution was not required, a worm density of 2 kg/m² could be used, worms preferred wetter environments, and system configuration did not affect effluent quality. Installing the first prototype in the UK proved that the process functioned when scaled, i.e., chemical oxygen demand and thermotolerant coliform reduction were found to be comparable with the laboratory results. Ten prototypes were then tested by households in rural India; all were working well after six months. The vermifilters were processing the amount of faeces entering the system on a daily basis, so faeces was not accumulating. It was estimated that they would require emptying after approximately five years, based on the depth of the vermicompost generated. With further development, it is believed that the Tiger Toilet has the potential to become a superior form of onsite sanitation, when compared with traditional onsite sanitation technologies.

Sanitation infrastructure are not able to cope with the increasing population in low-income countries, which leaves populations exposed to faecal contamination from multiple pathways. This study evaluated public health risk (using SaniPath) in a low-income community during the dry season, to identify the dominant exposure pathways, and compare this data to existing data for the rainy season, questioning the assumption that risk of faecal contamination is higher in the rainy season. SaniPath was used to collect and assess exposure and environmental data, and to generate risk profiles for each pathway. In the dry season the highest exposure frequency was for bathing and street food, exposure frequency generally increased, and seasonal variation was found in five pathways. The highest hazards in the dry season were through contact with drains, soil, and street food. Seasonal variation was found in the contamination of open drains and street food, with higher levels of Escherichia coli (E. coli) in the dry season. Open drains were identified as the most dominant risk pathway in both seasons, but risk was higher in the dry season. This highlights the complex nature of seasonal variation of faecal risk, and questions the assumption that risk is higher in the rainy season.

The technical performance and user acceptance of a novel on-site sanitation system based on vermifiltration was tested for over 12 months in rural India. Ten households (mean household size = 5.6 people) who had previously practised open defecation trialled a pour flush toilet linked to a vermifilter, together known as a ‘Tiger Toilet’. Technical parameters which were monitored over this period included: usage, temperature, accumulation of faecal matter and vermicompost, presence of worms, and influent and effluent quality. User satisfaction was evaluated relative to a baseline survey and through focus group discussions. The vermifilters processed human waste products effectively in a real life scenario. After 12 months there was little accumulation of faecal solids (0–10 per cent surface coverage) and effluent quality was good (chemical oxygen demand reduction = 57 per cent, faecal coliforms reduction = 99 per cent). Vermicompost accumulation was low and suggested that emptying would only be necessary ev...

During previous research into drinking water quality in Peru, it was found that water was becoming contaminated in households, and there was a lack of understanding surrounding this contamination. It was felt that returning these findings to the community could build capacity, enabling people to make more informed choices about drinking water practices. Several participatory methods were explored. Ketso®, a hands-on kit for engagement, was thought to provide the most appropriate approach, and was used to deliver several workshops in the community. Thirty-five participants explored their understanding of drinking water and factors that caused contamination. The method allowed them to explore these factors in depth and to develop several practical and simple solutions. One solution capitalized on a novel finding; participants associated the taste of chlorine with clean water, but were unaware that household bleach could be used as a cost-effective water treatment. Feedback was excellent, with Ketso seen as giving participants space to better understand and question their practices, whilst building capacity for change. This co-production of knowledge also allowed the researcher to gain a better understanding of local knowledge and perceptions. Such innovative knowledge exchange has important implications for future implementation of new water technologies and engineering projects.