Reducing health risks from wastewater use in urban and peri-urban sub-Saharan Africa: applying the 2006 WHO guidelines

Abstract

Where rapid urbanization is outpacing urban capacities to provide sound sanitation and wastewater treatment, most water sources in city vicinity are heavily polluted. This is of great concern as many of the leafy vegetables eaten raw in the cities are produced in these areas. Following the new WHO guidelines, different non-treatment options at farm, market, and kitchen level were field tested for health risk reduction with special consideration to efficiency and adoption potential. As most households are used to vegetable washing (although ineffectively), an important entry point for risk reduction is the increased emphasis of the new guidelines on food preparation measures. A combination of safer irrigation practices (water fetching, on-farm treatment, and application), the allocation of farmland with better water sources, and improved vegetable washing in kitchens appear to be able to reduce the potential risk of infections significantly, although it might not be possible to reach the ideal threshold without some kind of wastewater treatment. The on-farm trials carried out in Ghana also explored the limitation of other risk reduction measures, such as drip irrigation, crop restrictions and cessation of irrigation under local circumstances considering possible incentives for behaviour change.

Urban growth, wastewater production and use in irrigated agriculture: a comparative study of Accra, Addis Ababa and Hyderabad

“…These options can complement conventional wastewater treatment and, even where treatment is marginal, still provide at least some level of risk reduction. The IWMI has worked extensively on such non-treatment or post-treatment options, such as adjusting irrigation practices and awareness creation to support public health from 'farm to fork' (Drechsel et al 2008).…”

Perceived Health Hazards of Low-Quality Irrigation Water in Vegetable Production in Morogoro, Tanzania

“…This relates to the market challenges faced by traders forcing them to find an innovative way to gain the profit by reaching customers at their households' areas. Occupational health hazards such as physical pain from working with low-quality water in irrigation agriculture was also noted by Keraita et al (2008) study in Ghana. In contrary to the current study, these hazards were mentioned by older farmers and were mostly associated with the manual labor inputs and irrigation method used.…”

“…It is therefore advisable that the awareness campaign on health hazards reduction measures from using low-quality water in irrigation agriculture should target specific exposed group at all stages of the food chain (Lagerkvist Hess Okello Hansson & Karanja, 2013). As suggested by Drechsel et al (2008) people in our study sites should also be taught and offered cheap, suitable and low-cost methods for filtering low-quality water, such as drums filled with sand and watering can covered with cloth or mosquito netting so as to reduce the number of pathogens in the irrigation low-quality water. Furthermore, findings from the current study are important because successful implementation of low-quality water projects in irrigation agriculture should precede by clear information on the users' perceptions in using the resource as well as the health hazards experienced (Friedler, Lahav, Jizhaki, & Lahav, 2006).…”

“…In laboratory studies, it may be difficult to assess the health hazard and may overestimate or underestimate the actual health hazards. Studies by Keraita et al (2008) in West Africa and Gumbo et al (2010) in South Africa are examples of studies where farmers express their perception on the health hazards experienced from using low-quality water for vegetable production. In these studies, perceived health hazards mentioned included skin infections, nail problem commonly known as koilonychias, perceived health risk resulting from bad odor, bilharzias, diarrhea and cholera.…”

“…In these studies, perceived health hazards mentioned included skin infections, nail problem commonly known as koilonychias, perceived health risk resulting from bad odor, bilharzias, diarrhea and cholera. Evidence shows that respondents' perception of health hazards has an impact on how the hazard is managed (Keraita, 2008). Hence, this study aimed to (i) examine perceived health hazards of using low-quality water for irrigation vegetable production among vegetable farmers, traders, consumers and key informants living in Morogoro, Tanzania and (ii) assess the influence of age, sex, marital status, district where respondents belong and education level on the perception scale of the health hazards of using low-quality water in irrigated vegetable farming among vegetable farmers, traders and consumers.…”