# **Box  5.2 Ghana: From scratch, through the application of QMRA, to a national strategy**

Food safety is an important topic in Ghana which is addressed by various national and district entities under the leadership of the Food and Drug Board of the Ministry of Health. As is common in similar countries in SubSaharan Africa, there are multiple hazards affecting food safety in Ghana, from the sale of date-expired food items to non-compliance with the most basic rules of hygiene in markets and restaurants. The reasons for this range from poor educational levels and low risk awareness to the inability to invest in electricity (for cool storage) or access to water to maintain an appropriate level of hygiene.

Urban farmers who specialize in exotic ‘salad’ vegetables for the urban market have received significant negative media attention over the past few years due to the use of highly polluted water from drains and wastewater streams. As a result, the public authorities are well aware of this risk factor and are under pressure to address it. Although cholera outbreaks are a common feature in Ghanaian cities, there have been no means to analyse transmission pathways and the contribution of any particular hazard (see Box 5.3). The authorities did not know where to invest their limited resources and, as usual in such situations, the better known risk factors, such as personal hygiene and safe drinking water, usually have received priority. However, in an attempt to address the ‘obvious’ risks from wastewater use, the Ministry of Local Government asked the Environmental Protection Agency in 2002 to arrest farmers using polluted irrigation water. This later proved unrealistic since in Accra alone there are some 1,000 farmers whose livelihoods depend on the practice. Then the Ministry of Food and Agriculture (MoFA) asked the International Water Management Institute (IWMI) for research assistance. With directorates in every city, MoFA was concerned by the arrests of ‘its’ farmers, while it lacked the capacity to address the problem.

To apply the 1989 WHO guidelines—i.e., to treat the wastewaters the urban farmers were using to an acceptable level—or to ask them to change the cash crops they were growing appeared unrealistic, and the focus shifted to safety options that could be realized on the urban farms, in markets and in kitchens (Drechsel _et al_ ., 2002). Given the extremely high fecal coliform counts in the irrigation water (10<sup>6</sup> −10<sup>8</sup> per 100 mL) and the fact that the crops grown are usually eaten raw, the target was to minimize as far as possible the fecal coliform count at the point of consumption. This has been the target of a number of projects since 2004 which can be considered as an early local adaptation of the 2006 WHO Guidelines.

The projects analyzed the pathways of vegetable contamination from farm to fork and determined the number of farmers and consumers in all major cities. This allowed QMRA to be run and DALYs lost to be calculated. The projects then tested with farmers, traders and food caterers various non-treatment options as described in section 4.3.2. The most promising with the highest adoption potentials were selected to be part of a national strategy for health-risk reduction targeting two main entry points: various safer irrigation practices depending on the site, and improved vegetable washing in the street-food sector. The implementation of the strategy, which is not yet funded but at the proposal stage, would be based on four pillars—significant awareness creation, social marketing, incentives, and regulations—to achieve the best possible adoption of recommended practices (Karg _et al_ ., 2010). Based on the related implementation costs and the QMRA results, it was possible to calculate the cost-effectiveness of various combinations of safety practices— i.e., how much it would cost to avert a DALY. This analysis was carried out to understand in particular (i) how non-treatment options compare with wastewater treatment, and (ii)) how different adoption rates of non-treatment options affect their costeffectiveness (Seidu and Drechsel, 2010).

The cost-effectiveness analysis also showed that it would increase the implementation costs of the health strategy only marginally if other principles of basic hygiene would be included (e.g., vegetable washing and hand washing) while the number of averted DALYs could significantly increase.

Even though the recommendations focus on non-treatment options, the studies also concluded that wastewater treatment would be cost-effective in combination with non-treatment options, if some partially broken down treatment plants with farm sites in the vicinity would be rehabilitated and farmers agreed to move to those areas. The value addition through farming (including aquaculture) could support the cost of maintaining the plants (Murray and Buckley, 2010). Such a system has been earmarked by the African Water Facility for testing in Accra and Kumasi. In general, however, planned reuse and intersectoral collaboration are likely to be the exception as local institutions are overstretched by more basic problems.

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