Food additives and their health implications on children in Africa: a systematic review

Objective: The safety of processed foods is an issue of public health importance, especially in Africa where there is unchecked rate at which many food industries turn out novel 'chemicals' aimed at increasing the acceptability of their products. This is particularly true for processed foods targeted at children, who remain the most vulnerable group. The aim of this review was to identify health implications of food additives on children in Africa based on findings from original research works. Methods: We conducted a parallel search of Medline, EMBASE and Global Health for relevant studies from 1970 to 2014. We included studies conducted among African populations reporting effects of food additives among children (under age 17 years). Data on health implications of food additives were extracted and reviewed. Results: Our search returned 479 studies, with only 4 studies meeting the selection criteria. Five countries were represented, namely Libya, Nigeria, Uganda, Tanzania and Sudan The total study population was 3326. All the studies were cross-sectional, and focused essentially on sugar as an important risk factor for the development of dental caries and/or erosion in children. Conclusions: Studies on important food additives such as preservatives, colouring agents, sweeteners, anti-caking agents and their effects on health of children are largely unavailable in Africa, although anecdotal reports are suggestive of their deleterious effects. To ensure evidenced-based decision making and public policies in this regard, there is a need for original research works

Assessment of groundwater contamination by leachate near a municipal solid waste landfill

Physico-chemical and microbiological parameters were analyzed in leachate and groundwater samples obtained at different locations adjacent to a municipal solid waste landfill in order to assess the impact of leachate percolation on groundwater quality. Total dissolved solids (TDS), electrical conductivity (EC), and Na+ exceeded the World Health Organization (WHO) tolerance levels for drinking water in 62.5, 100, and 37.5% of the groundwater samples, respectively with pH and Fe exceeding WHO limits in 75% of the samples. Significant negative correlations of -0.839, -0.590, and -0.590 were shown by Na+, TDS, and EC respectively to distance from landfill. A high population of Enterobacteriaceae ranging from 4.0 × 103 ± 0 to 1.0575 × 106 ± 162,705 CFU/ml was also detected in the groundwater samples, indicating contamination. The results show that the leachate from the landfill has a minimal impact on the groundwater resource and this can be attributed to the existing soil stratigraphy at the site consisting of clay which is deduced to have a significant influence on the natural attenuation of leachate into groundwater.Keywords: Groundwater, correlation, percolation, landfill, leachate, municipal solid waste, natural attenuation, Enterobacteriaceae

An estimate of the prevalence of hypertension in Nigeria: a systematic review and meta-analysis

Background: Hypertension is a leading cause of morbidity and mortality in Africa, and Nigeria, the most populous country in the continent, hugely contributes to this burden.Objective: To provide an improved estimate of the prevalence and number of cases of hypertension in Nigeria based on the cut-off ‘at least 140/90 mmHg’, towards ensuring better awareness, control and policy response in the country.Methods: We conducted a systematic search of Medline, EMBASE and Global Health from January 1980 to December 2013 for population-based studies providing estimates on the prevalence of hypertension in Nigeria. From the extracted crude prevalence rates, we conducted a random-effects meta-analysis, and further estimated the overall awareness rate of hypertension in Nigeria, expressed as percentage of all hypertension cases. We applied a meta-regression epidemiological modelling, using United Nations population demographics for the years 2010 and 2030, to determine the prevalence and number of cases of hypertension in Nigeria for the 2 years.Results: Our search returned 2260 publications, 27 of which met our selection criteria. From the random-effects meta-analysis, we estimated an overall hypertension prevalence of 28.9% (25.1, 32.8), with a prevalence of 29.5% (24.8, 34.3) among men and 25.0% (20.2, 29.7) among women. We estimated a prevalence of 30.6% (24.5, 36.6) and 26.4% (19.4, 33.4) among urban and rural dwellers, respectively. The pooled awareness rate of hypertension was 17.4% (11.4, 23.3). The overall mean SBP was 128.6 (125.5, 130.8) mmHg, and the DBP was 80.6 (78.5, 82.7) mmHg. From our modelling, we estimated about 20.8 million cases of hypertension in Nigeria among people aged at least 20 years in 2010, with a prevalence of 28.0% (24.6, 31.9) in both sexes – 30.7% (24.9, 33.7) among men and 25.2% (22.7, 31.9) among women. By 2030, we projected an increase to 39.1 million cases of hypertension among people aged at least 20 years with a prevalence of 30.8% (24.5, 33.7) in both sexes – 32.6% (27.3, 38.2) among men and 29.0% (21.9–32.2) among women.Conclusions: Our findings suggest the prevalence of hypertension is high in Nigeria, and the overall awareness of raised blood pressure among hypertension cases is low in the country. We hope this study will inform appropriate public health response towards reducing this burden.</br