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Assessment of Grain Handling, Consumption and Risk of Exposure to Aflatoxins Among Adolescents in Secondary Schools Using Urinary Aflatoxin M1 Biomarker
(Enviro Research Publishers, 2025-07-25) Madoshi, Frank; Temba, Sylvester; Kassim, Neema
Aflatoxin contamination poses a significant public health concern, particularly in low-resource settings where dietary habits and food handling practices increase exposure risks to vulnerable populations. This study examined grain handling, consumption and the risk of exposure to aflatoxin among secondary school adolescents in Mvomero District, Morogoro-Tanzania. The study used a descriptive cross-sectional design employing stratified multistage proportionate sampling to obtain 396 secondary school adolescents and a non-probability, purposive sampling to obtain 33 teachers responsible for school meals from 33 schools. Data were collected using surveys, food frequency questionnaires and 24-hour dietary recalls. Urinary Aflatoxin M1 (AFM1) was analyzed using Enzyme-Linked Immunosorbent Assay (ELISA). The study was conducted across secondary schools in Mvomero district in Morogoro region of Tanzania, between February and May 2024. The findings revealed high aflatoxin exposure among secondary school adolescents in Mvomero District, Tanzania, with a median urinary AFM1 level of 0.035 ng/mL (IQR = 0.07 ng/mL), exceeding the hepatocellular cancer risk threshold of 0.0036 ng/mL. Higher AFM1 concentrations were significantly associated with the consumption of aflatoxin-susceptible grains (p < .05) and were notably higher in younger adolescents (0.039 ng/mL) than older ones (0.024 ng/mL; p = .04). Poor grain handling practices contributed to this exposure, as 96.9% of schools stored grains in non-protective polypropylene bags. Additionally, meals lacked diversity with 93.8% of schools relying mainly on maize and all using beans. Although a national school feeding guideline exists, none of the schools have begun its implementation, indicating a lack of enforcement. These results underscore the dual influence of diet and age on aflatoxin exposure and call for urgent interventions, including improved grain storage, enhanced public awareness, dietary diversification, and enforcement of school feeding policies to mitigate health risks in this vulnerable population.
Community Awareness and Health Risk of Heavy Metals Through Consumption of Sardine (Rastrineobola argentea) From Lake Victoria, Tanzania
(Wiley, 2025-09-03) Venant, Happiness; Lwetoijera, Dickson; Kassim, Neema
Sardine (Rastrineobola argentea) is a crucial food source for East African communities around Lake Victoria, providing essential
nutrients such as protein, amino acids, minerals, and vitamins. However, heavy metal contamination in aquatic environments
threatens its safety and may affect human health. This study assessed community awareness of heavy metal contamination
and estimated the health risks from sardine consumption in Lake Victoria, Tanzania. A cross- sectional study was conducted
in Mwanza, Kagera, and Mara regions. A semi- structured questionnaire assessed awareness and consumption, while a Flame
Atomic Absorption Spectrometer quantified cadmium and lead concentrations in sardine samples. About 80% of 425 participants
were women, and the majority (96.2%) were unaware of heavy metal contamination. Median concentrations in sardines were
0.081 ± 0.057 mg/kg (cadmium) and 0.012 ± 0.005 mg/kg (lead). Estimated daily intakes in mg/kg/day were cadmium (1.043
1.175 × 10−5) and lead (2.704–3.047 × 10−5). The target hazard quotients were 0.014 (cadmium) and 0.024 (lead), with hazard
indices ranging from 0.0053 to 0.0060. Target cancer risk values ranged from 1.03 × 10−9 to 1.70 × 10−5. Heavy metal levels in
sardines and daily exposure were within permissible limits set by national and international standards. Target hazard quotients,
hazard indices, and cancer risk values were all below tolerable limits, indicating no significant health risks from consuming
sardines from Lake Victoria. These findings suggest that although community awareness of the risk of heavy metal remains low,
the concentrations of cadmium and lead in sardines and the associated dietary exposure do not pose significant health risks to
consumers. The study recommends continuous monitoring, awareness campaigns targeting stakeholders, and promoting raised
racks for drying to reduce contamination. These findings offer preliminary evidence to inform decisions by environmental, food,
and fish authorities, local governments, and fishing communities, and raise awareness among traders and consumers.
Social Determinants of Physical Activity and Healthy Diet Consumption Among Adolescents Living With HIV in Ifakara town, Tanzania
(NM-AIST, 2025-08) Maganga, Justina
Insufficient physical activity and poor dietary habits are among the important risk factors for non-communicable diseases (NCDs) worldwide. While NCDs typically impact adults, these risk factors frequently emerge in adolescents, enhancing future NCD risk. In Tanzania, adolescents living with HIV (ALHIV) are at risk for NCDs due to HIV-related chronic inflammation and side effects of long-term antiretroviral therapy, as well as low physical activity and unhealthy eating. This qualitative study looked into the factors that influence physical activity and healthy diet consumption among ALHIV in Ifakara Town. A cross- sectional phenomenological qualitative study was conducted with ALHIV aged 15 to 19 and their parents and caregivers from the Kilombero and Ulanga Antiretroviral Cohort (KIULARCO). Between May and July 2024, 22 in-depth interviews with ALHIV were done, as were ten interviews with parents and caregivers. Thematic content analysis was carried out with NVivo 14 software. The coding approach employed both inductive and deductive coding techniques, with inductive codes obtained from the participants' tales and deductive codes developed using IDI guides and theoretical conceptions. The findings were theoretically categorized using the socio-ecological theory's intrapersonal, interpersonal, and community levels. Adolescents living with HIV and their parents/caregivers showed some awareness of physical activity and healthy eating and acknowledged the role of these behaviors in managing HIV and preventing NCDs. However, there were still gaps in their understanding. Physical activity among ALHIV was influenced by intrapersonal factors (limited time and inadequate knowledge); interpersonal (support from family and peers); and community-level (gender norms, negative perceptions, and lack of proper facilities). Similarly, healthy eating was shaped by intrapersonal factors (limited autonomy, weight concerns, and individual food
preferences); interpersonal factors (low household income and having a large family); and community-level influences (the widespread availability of fast food). The findings highlight a range of factors influencing both physical activity and dietary habits of ALHIV. This study underscores the need to involve the community, parents, and caregivers in the efforts to create a supportive environment that promotes a better lifestyle for ALHIV and tackles the barriers to physical activity and healthy eating. To further emphasize and reinforce these two health behaviors in this population, physical activity and nutrition education need to be incorporated into HIV care guidelines and programs as part of day-to-day HIV care.
Prevalence of Antibiotic-Resistant Escherichia Coli from Groundwater Sources and Sanitary Inspection for Contamination Risk in Bagamoyo District, Tanzania
(NM-AIST, 2025-07) Mduda, Joram
In Low and Middle-income Countries (LMICs), people have access to water but have no access to safe, clean, and protected water sources. Globally, two billion people consume water contaminated with faeces, with Escherichia coli being the most prevalent pathogen in polluted water, posing significant health risks. This underscores the urgent need to investigate resistant E. coli from groundwater sources and to conduct sanitary inspections. In the Bagamoyo District, a cross-sectional study was undertaken, examining 60 boreholes, 39 dug wells and 64 tube wells with hand-pumps. Escherichia coli was isolated through a membrane-filtration method, and the disc diffusion method was used in susceptibility testing according to Clinical and Laboratory Standards Institute (CLSI) standards. The study found E. coli contaminated
44.8% of groundwater samples and 83.6% of E. coli isolates were resistant to at least one antibiotic. Resistance was highly observed to cefazolin (56.16%) and nitrofurantoin (54.79%), Moreover, 70% of the E. coli isolates were multidrug-resistant, with an overall MAR-index of 0.28. Sanitary inspections revealed that dug-wells (46.2%) were at high contamination risk, and tube wells with hand pumps (32.8%) were at high and low contamination risk levels. Also, boreholes (73.3%) were at low contamination risk. High E. coli contamination was observed in boreholes despite of being at low contamination risk. Furthermore, groundwater sources
across contamination risk categories indicated high-rate-resistant E. coli contamination. Therefore, these findings highlight the presence of resistant E. coli from groundwater in Bagamoyo district and emphasize the necessity to promote proper antibiotic use to prevent contamination by resistant bacteria.
Effect of Arbuscular Mycorrhizal Fungi on Banana Growth during Hardening Phase and Field Phase in Northern Tanzania
(NM-AIST, 2025-08) Mapunda, Hellen
Banana production contributes significantly to sustaining food security of the rural communities in Tanzania. However, yieldsin smallholder banana fields only represent 10% of the production potential due to recurrent drought stress, declining soil fertility, and increasing pests’ pressure. Many plant species, including bananas, benefit from the presence of Arbuscular mycorrhizal fungi (AMF). Previous research on banana plants inoculated with AMF has shown encouraging outcomes. However, numerous studies have examined this under laboratory and screen house conditions. In light of this, field-based validation remains limited. In this context, two experiments were conducted in the northern highlands of Tanzania. The first experiment examined the effect of inoculating banana plantlets (var. Williams and Grand Naine) with three AMF strains (Rhizophagus intraradices, Rhizophagus irregularis and Rhizophagus clarus) on plant growth under nursery conditions. The results indicate that there were significant (p<0.05) and positive effects of AMF strains inoculation on banana plant growth parameters, with Rhizophagus intraradices recording the promising results compared to the control treatment. In the second experiment validated the effects of AMF strains with respect to growth and yield characteristics. The results show that Rhizophagus intraradices outperformed the other two strains. Overall, the results of this study indicate that AMF can be a useful addition to banana nursery management practices, resulting in improved growth and development during the critical weaning and hardening
phases and, as well as improved field establishing success. These findings may have positive consequences in banana production in the long-term. The findings could also aid in optimizing the conventional banana production techniques by integrating AMF inoculants for enhanced banana production.