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

Allergy sensitization and asthma among 13-14 year old school children in Nigeria

Background: The prevalence of asthma and role of atopy in asthma among children has not been clearly defined in Nigeria.Objective: To determine the prevalence of asthma and investigate risk factors related to allergy sensitization among urban and rural school children in southwest Nigeria.Methods: Validated ISAAC questionnaire was administered to 1736 high school children in randomly selected schools in rural and urban communities. Identified asthma cases were matched to controls. Allergy skin tests, blood eosinophil count, serum IgE and stool examination for parasites were performed. Dust samples from homes were also collected and analyzed for allergens.Results: The prevalence of asthma was 7.5% (95% CI 6.0 to 9.2%) and 8% (95% CI 6.0-10.4%) in the rural and urban communities respectively . Risk factors for asthma included cigarette-smoking, cats in the home and family size. Eosinophil count (109/L) was elevated in asthmatics [0.70 (95% CI 0.48-1.11) vs. 0.32 (95% CI 0.19-0.69); p<0.01], but IgE levels were similar between the two groups (298±229 IU/mL vs. 288±257; p=0.97). Positive skin tests to cat hair, cockroach, mango blossom and mouse epithelium were more frequent in asthmatics than in healthy controls, especially in the rural communities. There was no correlation between allergens in dust collected from homes and skin test reactivity.Conclusion: Asthma prevalence is similar in rural and urban children in Southwest Nigeria and atopy with elevated IgE was not observed to be a major factor for asthma in our cohort of children in both communities.Key words: Asthma, risk factors, prevalence, atopy, sensitization, childre

Comparative Catalytic Properties of Ni(OH)2 and NiO Nanoparticles Towards the Degradation of Nitrite (NO2 - ) and Nitric Oxide (NO)

Nitrite (NO2 - ) and nitric oxide (NO) have been identified as an environmentally hazardous analytes from discharged industrial effluents. Thus in this study, nickel oxide (NiO) and nickel hydroxide (Ni(OH)2) nanoparticles were synthesized using the complexation-precipitation method and their catalytic properties towards NO2 - and NO investigated. The success of the synthesised nanoparticles was confirmed using characterisation techniques, such as X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and the Fourier transformed infrared (FTIR) spectroscopy. The sizes of the synthesized NiO and Ni(OH)2 nanoparticles were estimated to be 5.39 and 5.07 nm respectively. The catalytic behaviour of NiO and Ni(OH)2 nanoparticles towards the oxidative degradation of NO and NO2 - in acidic and neutral media respectively was studied using UV-Vis spectrophotometer. Result indicated that NiO nanoparticles demonstrated better catalytic properties at different reaction time towards NO2 - and NO oxidation compared to Ni(OH)2, while NiO and Ni(OH)2 at nano scale showed enhanced catalysis towards the analytes compared with the bulk Ni salt. The bulk Ni salt did not show any sensing properties towards NO2 - . However in NO, the absorbance intensity due to the generation of nitrate (NO2 - ) was five times higher in the presence of NiO nanoparticles compared with the bulk Ni salt. The improved catalysis of Ni(OH)2 and NiO nanoparticles in this study was attributed to effective pore sizes and large surface area which expose the analytes to more catalytic site. The nanoparticles are simple to prepare, therefore can be used for the fabrication of a simple, portable, miniaturized nitrite and nitric oxide nanosensor for potential clinical and analytical application