Comparative Study of Bacteriological Quality of NAFDAC Registered and Unregistered Sachet Water Sold in Lafia Metropolis

Microbial contamination of packaged drinking water in Nigeria

“…Five (10%) of the studies reported assessing microbial contamination more than once [34–38] while the majority assessed this only once. Of the 52 included studies: two provided data on E. coli contamination only [39,40] eight assessed total coliforms only [34,37,41–46] sixteen assessed total coliforms and E. coli [10,35,36,47–59] fifteen characterised other bacteria in addition to E. coli [20,60–63]; total coliforms [38,64–66]; or total coliforms and E. coli [67–72] one study assessed TTC, total coliforms and E. coli [73] six other studies enumerated and characterised faecal coliform at 44–44.5°C within 48 h and we extracted the data as TTC [74,75], in addition to the total coliforms data reported [76–80]. two other studies also enumerated faecal coliform, however these were not characterised at the appropriate temperature [81,82].…”

“…Availability of these details would have provided a clearer understanding of the seasonality effects on the microbial quality of the sachet water products in Nigeria. Further, most of the studies reported contamination prevalence per brand with only four reporting this per the total number of samples collected and analysed [10,49,60,70]. Consequently, several studies showed a total that was lower than 10 even though samples were reportedly collected in triplicates.…”

“…• two provided data on E. coli contamination only [39,40] • eight assessed total coliforms only [34,37,[41][42][43][44][45][46] • sixteen assessed total coliforms and E. coli [10,35,36,[47][48][49][50][51][52][53][54][55][56][57][58][59] • fifteen characterised other bacteria in addition to E. coli [20,[60][61][62][63]; total coliforms [38,[64][65][66]; or total coliforms and E. coli [67][68][69][70][71][72] • one study assessed TTC, total coliforms and E. coli [73] • six other studies enumerated and characterised faecal coliform at 44-44.5°C within 48 h and we extracted the data as TTC [74,75], in addition to the total coliforms data reported [76][77]…”

“…Specifically, six of the 38 FIB articles characterised TTC while the remaining enumerated E. coli. Of the FIB studies, 15 reported non-detectable levels of E. coli or TTC and therefore showed zero risk of faecal contamination [36,40,[47][48][49]57,59,70,72,74,75,77,78,80,83]; five reported FIB contamination but did not quantity the number of samples that tested positive [39,[67][68][69]76]; while the remaining 18 studies showed crude FIB contamination prevalence ranging from 2.17 to 89% [10,20,35,[50][51][52][53][54][55][56]58,[60][61][62][63]71,73,79]. Overall, three studies each showed FIB counts = 1-10 CFU/100 ml [41,50,51] and 11-100 CFU/100 ml [10,53,71] indicating a low to moderate risk of faecal contamination, respectively.…”

“…Of the 45 articles that evaluated total coliforms contamination, six showed zero risk of contamination [49,57,59,74,77,78], three reported total coliforms contamination but did not quantify the number of positive samples or brands [39,69,76]; and the remaining 36 studies showed crude contamination prevalence ranging from 5.13 to 100%. Overall, five of the total coliforms articles reported counts of 1-10 MPN per 100 ml [41,47,65,67,81], 19 showed counts of 11-100 MPN per 100 ml [35,36,38,39,42,43,46,48,50,51,53,5 4,56,68,72,79,80,82,83], nine showed counts >100 MPN per 100 ml [34,52,55,58,[69][70][71]73,76] while the remainder did not quantify the bacteria counts.…”