Assessment of microbiological quality of sachet-packaged drinking water in Western Nigeria and its public health significance

Assessment of Foodborne Disease Hazards in Beverages Consumed in Nigeria: A Systematic Literature Review

Risk assessment is a formal process of identifying hazards and assessing the risk associated with them (risk is a combination of the severity of illness and the probability of occurrence). This review highlights foodborne disease hazards reported in beverages consumed in Nigeria for the period between 2000 and 2020. Based on a preregistered protocol and search syntax, studies were retrieved from the PubMed, Google Scholar, and ScienceDirect databases. Rayyan QCRI software was used to screen the articles. Data were then extracted from the included full-text articles, into a standardized excel workbook. A total of 18,762 articles were identified, from which 126 were included in the final analyses. The common beverages studied were sachet water (14.9%), borehole/well water (13.9%), cereal-based beverages (12.1%), raw/fresh milk (8.3%) and nono/nunu, which is a fermented milk-cereal beverage (7.2%). Sufficient data were available to undertake pooled prevalence estimates for some hazards within select beverages and revealed contamination rates for Staphylococcus spp. in raw/fresh milk, 12.3% (95% CI 6.3–20.0); Salmonella spp. in borehole/well water, 19.8% (95% CI 13.1–27.4); Klebsiella spp. in sachet water, 40.0% (95% CI 12.4–71.7); Staphylococcus spp. in nono/nunu, 32.6% (95% CI 14.7–53.8), and Escherichia spp. in nono/nunu, 30.7% (95% CI 21.9–40.2). Heterogeneity was present in the aggregate summary estimates. This review has highlighted the presence of several hazards of high importance to public health in commonly consumed beverages in Nigeria. The data presented here provide an entry point for future quantitative risk assessments both to determine the level of exposure of the community to these hazards and also for the identification of the most effective mitigation strategies to reduce these risks and improve health outcomes in Nigeria.

Microbial contamination of packaged drinking water in Nigeria

OBJECTIVES

About 18% of urban households in Nigeria depend on packaged sachet water as the primary source of drinking water. This review assessed microbial contamination of these products with an emphasis on total coliforms and the faecal indicator bacteria (FIB) - Escherichia coli (E. coli) and thermotolerant coliforms (TTC).

METHODS

PubMed/Medline, African Index Medicus, AfroLib, Global Health Library, Embase and the ISI Web of Science databases were searched to identify original research published up to October 2020. The literature findings were synthesised narratively in line with the review objectives. To assess prevalence of microbial contamination, a random effects meta-analysis, was also conducted using the R metafor package in RStudio. The protocol for this review is registered on PROSPERO with reference number CRD 42019128474.

RESULTS

Fifty-two of 429 studies were identified for inclusion. At 53.27%, contamination prevalence was higher for total coliforms (95% CI: 39.05-66.98, I²  = 81%, p < 0.01, 42 studies) than FIB (12.38%, 95% CI: 7.92-18.85, I²  = 61%, p < 0.01, 33 studies) suggesting that treatment failure is a major contributor to the poor microbial quality reported in the included studies. Within the FIB group, the prevalence of contamination with E. coli was 13.30% (95% CI: 8.23-20.80, I²  = 65%, p < 0.01, 27 studies) versus 6.24% (95% CI: 1.12-28.06, I²  = 72%, p < 0.01, six studies) for TTCs. Other microbial contaminants reported were Pseudomonas aeruginosa, Klebsiella and Enterococcus faecalis and these showed multidrug antibiotic resistance.

CONCLUSIONS

The findings of this review highlight the need for improved regulatory oversight with more stringent monitoring of the microbial quality of sachet water products in Nigeria.

Sachet water quality and Vendors’ practices in Damongo, northern Ghana during the emergence of SARS-CoV-2 using multivariate statistics, water quality and pollution indices, and panel assessment

The emergence of the SARS-CoV-2 has affected several production services including the water production and delivery processes. This study considered sachet water quality during the advent of the SARS-CoV-2 pandemic using multivariate statistics and Water Quality Index, Water Pollution Index and, hygienic and sanitation practices of sixty-two (62) sachet water vendors using a panel assessment approach. The findings showed that vendors did not adhere to proper hygienic practices as ninety-four (94%) of them did not have health clearance, ninety (90%) did not frequently wash their receptacles for selling daily, and most of them stored and sold in unhygienic environments. Majority of the producers violated Food and Drugs Authority Regulations. The Empirical Orthogonal Function analysis showed that total iron, Total Heterotrophic Bacteria, Salmonella, Cl⁻, E. coli, and fecal and total coliforms were the controlling elements in the water. All the brands were below threshold limits based on the physical water assessment. However, enteric bacteria were observed in all the brands. Water Quality and Water Pollution Indices (WQI and WPI) described all the sachet water brands (vendors and production sites) as excellent for drinking. The WQI computations for samples from the production and vending sites respectively ranged from 0.12 to 0.36 and 0.27–0.42 whereas WPI presented 0.22–0.31 and 0.23–0.32. Comparatively, samples from vendors had elevated elemental concentrations and loads. This suggests that besides sachet water contamination during production and transportation, vendors significantly impacted the quality of sachet water. Sensitization on proper hygienic practices for sachet water production and vending and routine assessment of the quality of sachet water produced or sold is recommended.

A comprehensive review of water quality monitoring and assessment in Nigeria

Nigeria is the most populated black nation in the world with about 199 million people. About 66.3 million Nigerians do not have access to safe drinking water. In this study, research findings on water quality monitoring and assessment in Nigeria over the past two decades were systematically reviewed. There are still grave enforcement issues in Nigeria as quality guidelines are still being contravened at no cost to the infringer due to the corrupt socio-political circumstances of the country. The quality of surface water, groundwater, rainwater and commercially available water was discussed in line with their pollution sources. The quality of surface water was generally poor. Groundwater pollution has come due to landfill leachate, oil and gas exploration and production, sewage and hydrogeological interactions of the groundwater with the base rock. The hydrogeological effect has led to the observation of lead and barium in groundwater in many locations across the country. The main issue with rainwater in Nigeria is the low pH but it was observed to be fairly clean. Commercially available water (bottled or sachet) is currently the best source of drinking water for the Nigerian populace. Bottled water quality is higher than for sachet water and the latter largely influenced by microbe contamination. Future perspectives in water quality monitoring and assessment are suggested in the evaluation of emerging contaminants and micro-pollutants and the utilisation of internet-enabled technologies.

Water quality for young children in Cambodia-High contamination at collection and consumption level

Unsafe drinking water is a leading cause of child morbidity, especially among young children in low‐income settings. Safe water consumption requires high‐quality water available at its source and at point of use. We examined the quality of drinking water at point of collection and point of use in 796 households in three provinces, in Cambodia. Microbiological testing for coliform and Escherichia coli contamination was conducted for samples collected. Bivariable analysis and multivariable logistic regression were used to examine associations between various factors and the deterioration in water quality (increase in the risk according coliform or E. coli concentration) between point of collection and point of use. Contamination with both coliforms and E. coli was higher at point of use than at point of collection, with contamination at point of collection to account for 76.6% (coliforms) and 46.3% (E. coli). Results suggest that child drinking water represents a considerable pathway for the ingestion of pathogens, in Cambodia. Area of residence, seasonality, type of water source, and water chlorination were associated with coliform concentration between the point of collection and point of use, whereas only seasonality was associated with E. coli contamination (OR = 1.46; 95% CI [1.05, 2.02]). Children living in rural settings were two times more likely to drink water with a deteriorating coliform concentration between the two‐time points than children living in urban settings (OR = 2.00; 95% CI [1.22, 3.30]). The increase in coliform and E. coli concentrations between point of collection and point of use indicates that water contamination mostly occurs within the household. Strengthening national legislation on water quality standards and promoting safe water management at the household are needed.

Microbiological assessment of sachet water "pure water" from five regions in Ghana

Background: Sachet water, popularly known as “pure water” has become an invaluable entity in most Ghanaian households. Despite its importance, there is no extensive nationwide investigations on its wholesomeness for consumption. The aim of this study was to determine the microbiological quality of 41 brands of sachet water sampled in 16 districts across 5 regions in Ghana.

Methods: The samples were analyzed for the presence of total and fecal coliform ( Escherichia coli) using the Colilert*- 18 Test Kit.

Results: Majority of the samples (56.09%) were excellent, 4.87% satisfactory and 14.63% suspicious. Ten samples (24.4%) were unsatisfactory. For the degree of fecal contamination, (85.56%) were satisfactory, four (9.76%) were suspicious, and two others (4.88%) were unsatisfactory. The contaminations observed could be attributed to poor sanitary conditions (during and/or after production) and failure of some production facilities to adhere to standard manufacturing practices.

Conclusion: Our data suggest that microbiological quality sachet water from some sources have not yet attained levels that make it absolutely pure and wholesome for consumption in many areas.

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.

Microbiological assessment of sachet water “pure water” from five regions in Ghana

Background: Sachet water, popularly known as “pure water” has become an invaluable entity in most Ghanaian households. Despite its importance, there is no extensive nationwide investigations on its wholesomeness for consumption. The aim of this study was to determine the microbiological quality of 41 brands of sachet water sampled in 16 districts across 5 regions in Ghana. Methods: The samples were analyzed for the presence of total and fecal coliform (Escherichia coli) using the Colilert*- 18 Test Kit. Results: Majority of the samples (56.09%) were excellent, 4.87% satisfactory and 14.63% suspicious. Ten samples (24.4%) were unsatisfactory. For the degree of fecal contamination, (85.56%) were satisfactory, four (9.76%) were suspicious, and two others (4.88%) were unsatisfactory. The contaminations observed could be attributed to poor sanitary conditions (during and/or after production) and failure of some production facilities to adhere to standard manufacturing practices. Conclusion: Our data suggest that microbiological quality sachet water from some sources have not yet attained levels that make it absolutely pure and wholesome for consumption in many areas.

Health risk assessment of heavy metal variability in sachet water sold in Ado-Odo Ota, South-Western Nigeria

The sales of sachet water (SW), also known as "pure water" (PW), in Nigeria is a lucrative business. It serves many people, especially low-income earners, by providing a more affordable access to safe drinking water when compared with table water. However, some of the producers of SW do not effectively treat raw water before packaging them for sale. This study investigates the presence and concentrations of heavy metals, such as chromium (Cr), iron (Fe), manganese (Mn), copper (Cu), aluminum (Al), and zinc (Zn) in some samples of SW sold within Ota, Ogun State, Nigeria. Samples of SW from nine different producers were purchased for four consecutive weeks and analyzed to determine the concentrations of these heavy metals in them. Furthermore, health risk indicators, such as chronic daily intake (CDI) and health risk indices (HRI) for children and adults, were calculated separately. The metal concentrations were compared with allowable limits set by the World Health Organization (WHO), Nigerian Industrial Standard (NIS), and the United States Environmental Protection Agency (US EPA). High concentrations of Cr, Fe, and Al were found in all the nine samples and exceeded the maximum allowable limits (MAL) of all the standards considered. However, the concentrations of Zn, Mn, and Cu were within permissible limits. The HRIs of heavy metals were in the order of Cu > Fe > Zn > Mn > Al > Cr, but since the standard limits set for some metals were exceeded, proper and effective treatment is required to safeguard the health of consumers.

The role of food processing and appropriate storage technologies in ensuring food security and food availability in Africa

Purpose

This paper aims to review scientific contributions that are essential to reduce the challenges to food security in Africa through food processing and appropriate storage technologies.

Design/methodology/approach

Several literature studies on the role of food processing and appropriate storage technologies in ensuring food security and food availability in Africa were critically reviewed.

Findings

The study revealed that the world faces multiple challenges to food security including under nutrition and overconsumption, rising food prices, population growth, rapid diet transitions, threats to agricultural production, inefficient production practices and supply chains and declining investment in food system research. Many people lack adequate amounts of foods that are rich in the nutrients needed for a healthy and productive life. According to FAO, 1996, chronic undernutrition affects 43 per cent of the Africa’s population or some 215 million people in sub-Saharan Africa. Food security is highly instrumental to the economic growth and sustainability of any country. The use of simple but effective on- and off-farm storage facilities and agro-processing technology should be promoted to add value to products and increase their shelf-life. The Strategic Grain Reserve Scheme should be modernized, strengthened and upgraded to a National Food Reserve Program, which will enable it to handle all staples and essential food products. This will help in attainment of national food security goal. It is also crucial to promote and develop agro-processing in the various African countries for the evolution of virile agro-allied industries and rural micro-enterprises.

Research limitations/implications

The paper reviewed the role of food processing and appropriate food storage technologies in ensuring food security and availability in Africa. There are insufficient data and information on adoption of new food processing and appropriate storage technologies in Africa. Although, there have been some instances where the introduction of modern techniques has resulted in products rejection by consumers.

Practical implications

The paper helps in reviewing food situation in Africa and how to make food available for the people and Africa food secured.

Social implications

This paper revealed strategies that could be used to improve food security and ensuring food availability in Africa.

Originality/value

This review paper is of value to policymakers, government agencies responsible for food quality control and assurance and consumers to make food available and affordable for the people.

Use of Lactobacillus plantarum as Starter Culture and Its Influence on Physicochemical, Microbiological, and Sensory Characteristics of Kunnu-Aya Produced from Sorghum and Tigernut

Kunun-aya is a traditional nonalcoholic beverage in the northern part of Nigeria, normally prepared from cereals. In this investigation Lactobacillus plantarum, isolated from fermenting kunun, was applied as starter culture during production of kunun-aya from varying combinations of sorghum and tigernut. The quality attributes of the product indicated increase in ash and protein contents of product inoculated with starter culture (PISC) over the uninoculated control sample (UCS). The highest values of 4.43% and 6.95% were recorded for ash and protein, respectively, in the product from fifty percent each of sorghum and tigernut (50SOR/50TIG). Titratable acidity was higher in PISC compared to UCS; the 50SOR/50TIG sample had the highest value of 0.92. The PISC recorded reduced counts of Salmonella, coliforms, and Staphylococci. The SCIS were preferred by panellists in the sensory attributes of appearance, aroma, taste, mouthfeel, and general acceptability. It was concluded that the use of L. plantarum as starter culture in the production of kunun-aya was advantageous as a result of enhanced nutritional, sensory, and microbial qualities recorded compared to UCS. Reduction in Salmonella, coliforms, and Staphylococci in PISC may be of public health significance. This on quality improvement of the traditional beverage has not been previously reported.

A Systematic Review and Meta-Analysis of Fecal Contamination and Inadequate Treatment of Packaged Water

BACKGROUND

Packaged water products provide an increasingly important source of water for consumption. However, recent studies raise concerns over their safety.

OBJECTIVES

To assess the microbial safety of packaged water, examine differences between regions, country incomes, packaged water types, and compare packaged water with other water sources.

METHODS

We performed a systematic review and meta-analysis. Articles published in English, French, Portuguese, Spanish and Turkish, with no date restrictions were identified from online databases and two previous reviews. Studies published before April 2014 that assessed packaged water for the presence of Escherichia coli, thermotolerant or total coliforms were included provided they tested at least ten samples or brands.

RESULTS

A total of 170 studies were included in the review. The majority of studies did not detect fecal indicator bacteria in packaged water (78/141). Compared to packaged water from upper-middle and high-income countries, packaged water from low and lower-middle-income countries was 4.6 (95% CI: 2.6-8.1) and 13.6 (95% CI: 6.9-26.7) times more likely to contain fecal indicator bacteria and total coliforms, respectively. Compared to all other packaged water types, water from small bottles was less likely to be contaminated with fecal indicator bacteria (OR = 0.32, 95%CI: 0.17-0.58) and total coliforms (OR = 0.10, 95%CI: 0.05, 0.22). Packaged water was less likely to contain fecal indicator bacteria (OR = 0.35, 95%CI: 0.20, 0.62) compared to other water sources used for consumption.

CONCLUSIONS

Policymakers and regulators should recognize the potential benefits of packaged water in providing safer water for consumption at and away from home, especially for those who are otherwise unlikely to gain access to a reliable, safe water supply in the near future. To improve the quality of packaged water products they should be integrated into regulatory and monitoring frameworks.

Fecal contamination of drinking-water in low- and middle-income countries: a systematic review and meta-analysis

BACKGROUND

Access to safe drinking-water is a fundamental requirement for good health and is also a human right. Global access to safe drinking-water is monitored by WHO and UNICEF using as an indicator "use of an improved source," which does not account for water quality measurements. Our objectives were to determine whether water from "improved" sources is less likely to contain fecal contamination than "unimproved" sources and to assess the extent to which contamination varies by source type and setting.

METHODS AND FINDINGS

Studies in Chinese, English, French, Portuguese, and Spanish were identified from online databases, including PubMed and Web of Science, and grey literature. Studies in low- and middle-income countries published between 1990 and August 2013 that assessed drinking-water for the presence of Escherichia coli or thermotolerant coliforms (TTC) were included provided they associated results with a particular source type. In total 319 studies were included, reporting on 96,737 water samples. The odds of contamination within a given study were considerably lower for "improved" sources than "unimproved" sources (odds ratio [OR] = 0.15 [0.10-0.21], I2 = 80.3% [72.9-85.6]). However over a quarter of samples from improved sources contained fecal contamination in 38% of 191 studies. Water sources in low-income countries (OR = 2.37 [1.52-3.71]; p<0.001) and rural areas (OR = 2.37 [1.47-3.81] p<0.001) were more likely to be contaminated. Studies rarely reported stored water quality or sanitary risks and few achieved robust random selection. Safety may be overestimated due to infrequent water sampling and deterioration in quality prior to consumption.

CONCLUSION

Access to an "improved source" provides a measure of sanitary protection but does not ensure water is free of fecal contamination nor is it consistent between source types or settings. International estimates therefore greatly overstate use of safe drinking-water and do not fully reflect disparities in access. An enhanced monitoring strategy would combine indicators of sanitary protection with measures of water quality.

When urban taps run dry: sachet water consumption and health effects in low income neighborhoods of Accra, Ghana

Intraurban differentials in safe drinking water in developing cities have been exacerbated by rapid population growth that exceeds expansion of local water infrastructure. In Accra, Ghana, municipal water is rationed to meet demand, and the gap in water services is increasingly being filled by private water vendors selling packaged "sachet" water. Sachets extend drinking water coverage deeper into low-income areas and alleviate the need for safe water storage, potentially introducing a health benefit over stored tap water. We explore correlates of using sachets as the primary drinking water source for 2093 women in 37 census areas classified as slums by UN-Habitat, and links between sachet water and reported diarrhea episodes in a subset of 810 children under five. We find that neighborhood rationing exerts a strong effect on a household's likelihood of buying sachet water, and that sachet customers tend to be the poorest of the poor. Sachet use is also associated with higher levels of self-reported overall health in women, and lower likelihood of diarrhea in children. We conclude with implications for sachet regulation in Accra and other sub-Saharan cities facing drinking water shortages.