Sachet water quality and product registration: a cross- sectional study in Accra, Ghana

The study’s objectives were to assess the extent to which packaged water producers follow product registration procedures and to assess the relationship between product registration and drinking water quality in Accra, Ghana. Following preliminary analysis of a national water quality survey, 118 packaged sachet water samples were collected by sampling all brands sold by 66 vendors. A sample of vendors was selected from two high-income and two low-income areas of Accra, Ghana. Sachet packaging and labelling details were recorded and compared to a regulatory database to assess product registration. All samples were weighed and tested for faecal indicator bacteria and selected physico-chemical parameters. Product registration numbers and brand names could be matched to regulatory records for 77 of 118 sachets (65.2%). All samples tested were compliant with national water quality standards for faecal indicator bacteria and nitrate. Brand registration was not associated with any of the quality indicators considered. The results of this study suggest that while a substantial proportion of sachet water is sold without formal product registration, the microbial quality of the unlicensed water is consistently high in Accra, Ghana. Further examination of regulatory enforcement and monitoring will be needed to ensure sustained high water quality over time. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licence (CC BY 4.0), which permits copying, adaptation and redistribution, provided the original work is properly cited (http://creativecommons.org/licenses/by/4.0/). doi: 10.2166/wh.2018.055 om http://iwaponline.com/jwh/article-pdf/16/4/646/372249/jwh0160646.pdf 2021 M. Dzodzomenyo W. Dotse-Gborgbortsi G. Aryeetey N. Coleman School of Public Health, University of Ghana, P.O. Box LG13, Legon, Accra, Ghana G. Fink Swiss Tropical and Public Health Institute and University of Basel, Basel, Switzerland N. Wardrop J. Wright (corresponding author) Geography and Environment, University of Southampton, Highfield, Southampton SO17 1BJ, UK E-mail: j.a.wright@soton.ac.uk A. Hill Social Sciences, University of Southampton, Highfield, Southampton SO17 1BJ, UK


INTRODUCTION
Packaged drinking water consumption is growing rapidly in West Africa and in other low-and lower-middle-income countries (Rodwan ). Unlike in high-income countries, this growth in packaged water consumption has taken place against a background of partial and interrupted piped water coverage in urban sub-Saharan Africa (Stoler et al. a, b). In particular, sachet water, drinking water (typically 500 mL) sold in heat-sealed plastic sleeves, has proved a popular supplement to piped water among urban consumers in many settings. In Ghana, the percentage of households reporting bottled water or sachets as their main source of drinking water increased from 9.2% While certification with the GSA is voluntary, registration with the FDA is compulsory and entails health checks on staff, compliance with safe production, labelling (e.g., a producer address and 'best before' date) and handling practices (Ghana Standards Authority a), and water quality testing of the product. However, given limited resources, regulation of the sachet water industry remains a challenge.
In particular, there are concerns about wholesalers and small-scale unregistered producers (Stoler et al. b) operating outside this regulatory framework, whose sachets may therefore present a greater contamination and public health risk, particularly in poorer urban Ghanaian neighbourhoods (Stoler et al. ). Greater exposure to more contaminated drinking water has also been observed among deprived neighbourhoods and households in other countries and supply systems (Yang et al. ; Delpla et al. ). More generally, a complex interplay of economic and social factors determines the outcome of diarrhoea for example, with sanitation infrastructure, hygiene behaviours, and community cohesion directly affecting its transmission (Fewtrell et al. ; Zelner et al. ). Despite such concerns, a recent nationally representative household survey, the Ghana Living Standards Survey Round 6, found lower rates of detectable Escherichia coli in sachet samples compared to point-of-consumption samples from piped systems (Johnston & Amoako-Mensah ). Visits to several small-scale sachet production premises in Accra suggested that most were packaging piped water from the municipal system (Stoler et al. b). However, packaging of groundwater from boreholes, following treatment via reverse osmosis, has also been observed for three production facilities in Dodowa, north of Accra (Gronwall & Oduro-Kwarteng ).
There is widespread recognition that water safety should be assessed by examining risk management arrangements in addition to water quality monitoring. This approach is embodied, for example, in the water safety plan concept (Davidson et al. ), but also with greater recognition of 'safely managed' water services in proposals for post-2015 international monitoring of safe water access (World Health Organization & UNICEF , ). This is because, for many water sources, contamination events may be sporadic and intermittent quality testing may therefore miss such This study therefore aims to assess the extent to which local sachet water producers follow national product registration laws, as well as the degree to which unlicensed water meets national water quality standards in both relatively wealthy and relatively poor neighbourhoods of Accra, Ghana. It also aims to examine the inter-relationship between labelling, packaging quality, price and market penetration on the one hand and sachet water quality and brand registration status on the other.

Sampling for primary fieldwork
The sampling strategy was designed to cover the entire spectrum of sachet water brands sold in rich and poor neighbourhoods within Accra. To identify rich versus poor neighbourhoods, we developed a deprivation index for enu- Based on the PCA score, we classified all EAs into deprivation quintiles, and then selected four EAs from the two most deprived quintiles (deprived neighbourhoods) and eight areas from the two least deprived quintiles (wealthy neighbourhoods, generally with fewer stores) for the study.
We reviewed Google Earth satellite imagery from 12 January 2010 and 20 March 2016 to ensure that there had been no major changes to the built environment following the 2010 census at these sites. All water vendors operating from fixed premises, kiosks or shops in and immediately surrounding each EA were mapped. Street hawkers were excluded. In the first phase, 16 sachet vendors were selected from those listed as being closest to a set of randomly selected households with young children participating in a pilot intervention study (Wright et al. a). In the second phase, 50 vendors were selected using simple random sampling from the list of eligible vendors.

Power calculations
Based on a national rate of 20% detectable E. coli in pointof-sale sachet water in the 2012-13 Ghana Living Standard Survey (Wright et al. b) and assuming a 20% difference in sachet contamination between rich and poor areas, we estimated that 118 samples would be required to detect 10% sachet contamination in least deprived EAs versus 30% contamination in those most deprived (with alpha ¼ 0.05 and 80% power).
Sachet collection and assessment of product In the second phase, sachets were also weighed in the laboratory prior to testing, to assess deviations from the stated, standard 500 mL sachet volume. Individual sachet brand weights were measured using a Mettler Toledo (PM 600) weighing scale which was calibrated every six months. Each sample was weighed three times and the mean weight recorded to the nearest 0.01 g. We also weighed a small sample of primary packaging and found it weighed on average 2 g. Assuming a water density of 0.996 g/cm 3 at an ambient temperature of 30 C (Jones & Harris ), a 500 mL sachet should weigh 497.8 g þ 2 g for packaging or approximately 500 g.

Analysis
We start with descriptive statistics of the number of brands sold by vendors, packaging characteristics, sachet prices and brand registration, and describe water quality test results. We also assess the extent to which vended sachets contained the stated quantity (500 mL) of water. To examine the suggestion that unregistered brands are more likely to be sold cheaply in poorer neighbourhoods (Stoler et we examine the relationship between brand registration with the FDA, price and neighbourhood deprivation for the EA at point-of-sale using logistic regression. Through this analysis, we also examine brand registration in relation to visual indicators of production process problems that are apparent to consumers. These include deviations from the stated sachet weight and signs of poorer quality packaging, such as frayed heat-seals. Finally, we examine the relationship between product registration and brand characteristics that could be perceived as quality indicators by consumers, namely, being part of the leading franchise, market penetration (measured by the proportion of vendors selling a given brand) and labelling on primary packaging.
Due to small cell counts, Fisher's exact test was used to examine these brand characteristics relative to FDA registration status.

Survey 6
A recent study in a Nigerian city found evidence of seasonal microbial contamination of sachet water (Kumpel et al. ). Therefore, to assess whether packaged water in Ghana was also subject to seasonal contamination in response to initial reviews of this study, we examined data from a nationally representative multi-stage cluster survey, the Ghana Living Standards Survey 6 (GLSS6) conducted from October 2012 to October 2013, which included a water quality module (Ghana Statistical Service ). The GLSS6 sampled 15 households in each of 1,200 EAs nationally, resulting in 18,000 participating households. Of these, a random sample of three households in each EA was asked for 'a glass of water as though for a child to drink'. Among selected households, 550 were using sachets for drinking water and in these households, the sachet was first poured into a glass prior to sampling. Sampling took place via continuous, parallel survey of each of Ghana's ten regions over the 12-month period. Samples were then tested for E. coli and total coliforms, following methods previously described elsewhere ( Johnston & Amoako-Mensah ; Wright et al.

b).
To test for seasonal variation in microbiological contamination of sachets, we grouped dates of sample collection into four quarters (Jan-Mar; Apr-Jun; Jul-Sep; and Oct-Dec) since very few samples were collected in June and December. As noted in our previous analysis of the GLSS6 microbiological data (Wright et al. b), digit preference and rounding when enumerating E. coli gave rise to unusually large numbers of samples with colony forming unit (cfu) counts such as 10 and 100. To avoid such rounded cfu counts when distinguishing between low, medium and high contamination of sachets, we therefore reclassified the E. coli counts as low (<1 cfu/100 mL), medium (1-72 cfu/100 mL) or high (>72 cfu/100 mL). We then cross-tabulated contamination levels against quarter, using the svy set of commands in Stata to take account of the survey design and calculating an F-statistic (Rao & Scott ) to test for seasonal variation in E. coli contamination.

Primary fieldwork
Combining both fieldwork phases, 34 of the 66 sampled vendors sold one brand, 18 sold two brands, nine sold three brands, four sold four brands, and one sold five brands.
This gave a total of 118 sachet samples, since one sample was taken of each brand sold per vendor (vendor-brands).
Overall, the samples taken from these vendors represented 33 different sachet brands. Sachets with specific brands were however not all produced in the same factory, and some factories produced multiple brands. The most widespread brand was manufactured under franchise, so this one brand was produced at 13 different factories. Furthermore, three factories manufactured two different sachet brands rather than a single brand. Given that product registration with the FDA varied within this franchise, we work hereafter with the 43 unique combination of factory and brand (producer-brands) as the unit of analysis, considering each franchise separately. Table 1 summarises the packaging quality and prices of vendor-brands. No sachet samples contained visible particles and there were no sachets with a discernibly poorer 'feel' to the plastic. Table 1   As shown in Figure 1, despite being labelled as containing 500 mL of water, which should weigh 500 g, sachets from the second round of sampling weighed only 480.3 g on average (standard deviation: 18.9 g; n ¼ 78).

Water quality
Six out of 118 samples were mislaid by the processing laboratory and therefore lacked test results and weights. Of the remainder, all samples were <1 cfu per 100 mL and so compliant with national standards for E. coli and total coliforms, and also compliant with national standards for heterotrophic plate counts (50 cfu/mL and 500 cfu/mL, respectively, when incubated at 22 C and 37 C (Ghana Standards Authority )). Table 2 shows physico-chemical water quality test results for the 112 sachet water samples.  These were all compliant with national standards for nitrate.
When electro-conductivity was converted to total dissolved solids, all sample values were well below 300 mg/L, the threshold above which panels of water tasters begin to detect a salty taste (World Health Organization ).
Sachet and brand characteristics associated with registration with the FDA  and 502 grams (representing the weight of 500 mL of water plus 2 g of packaging) was significantly related to brand registration, although poor print colour approached significance in predicting non-registration of brands.

Secondary data analysis of Ghana Living Standards
Survey 6  low. We also find no evidence that those in more deprived neighbourhoods were more likely to consume faecally   The recent systematic review by Bain et al. () excluded studies that did not differentiate between brands and sampled less than ten brands. By recording and sampling a range of brands, our study both meets the review inclusion criteria and confirms the general trend in this wider pool of studies. However, our study also suggests that there is a complex relationship between sachet production and branding. Production of a leading sachet brand is franchised to multiple producers, while a single factory may produce more than one brand. This suggests that where such details are available, production addresses as well as brands should be recorded in market surveillance of packaged water quality.
In keeping with another study of water packaging in Africa, our study identified some aspects of packaged water that were not compliant with legislation. A Nigerian study of 92 sachet water samples found no samples had printed 'best before' dates and 7% of sampled sachets lacked manufacturer addresses and NAFDAC registration numbers (Olaoye & Onilude ). However, while printed 'best before' dates required by the FDA were rare both in this study and our own data, it seems unlikely that bulky, low margin goods such as sachets would be stored for long periods by either retailers, wholesalers or manufacturers given the costs associated with doing so. Vendor questionnaire responses also support this, with deliveries on a weekly basis, or more frequently, for most vendor-brand combinations (Table 1), suggesting this is not a significant public health concern. The majority of sachets we sampled were also under the labelled volume (Figure 1) This may occur, for example, if sachet water is transferred to other containers prior to consumption. There are also difficulties with some aspects of our study protocol. For example, our findings are dependent on the currency, accuracy and completeness of the FDA database of registered products, and record linkage will be affected by changes of address by registered manufacturers. There is also scope for further refinement to our sampling protocol, for example, in recording whether sachets are labelled as mineral water on packaging. Finally, growing sachet consumption suggests that Ghana's sachet industry is evolving rapidly and our findings should be interpreted within this context.

CONCLUSIONS
This study suggested that in both low and high deprivation neighbourhoods of Accra, water sachets were compliant for water quality parameters tested, and most brand details printed on packaging matched to regulatory records of registered producers. These results provide further evidence of the comparative safety of sachet water in Ghana, although issues such as the extent and frequency of regulatory inspection of producers' premises and franchising of production