The Mambaka watershed is extends between latitudes 1 3°45'E and 14°15'E and longitudes 7°16'N and 6°45'N. The geology, various tectonic and structural events that have affected the Adamawa Plateau in Cameroon make it rich in multi-substance mining. The objective of this study is to map rare earth (REE) geochemical anomalies in the sediments of the watershed streams west of Mambaka, and to trace their origins and geochemical processes. Predictive maps from inverse distance interpolations (IDW), factor analysis (F1) or principal component analysis (PCA) and hierarchical bottom-up classification maps provided a better understanding of the central tendency, distribution and dispersion of REE in the samples and in the study area, based on standard deviation and variance values that generated two factors F1 (Ho-Tm-Er-Yb-Lu-Dy-Tb-Gd-Eu-Sm) and F2 (Pr-Nd-Ce-La-Sm) representing 92.44% of the total cumulative variance. The ratios Ce/Ce* > 0.78 and Eu/Eu* > 1 demonstrate positive anomalies in Ce and Eu, and clear differentiation. The normalized concentrations used to calculate fractionation ratios show that the values for LaN/YbN (0.58 to 1.34), LaN/SmN (0.61 to 0.88) and LaN/LuN (0.62 to 1.43) suggest higher fractionation in SS09 and lower fractionation in SS01. Similarly, the ratios La/Lu (61.71 to 143.46), La/Yb (9.00 to 20.72), La/Sm (4.02 to 5.83) and La/ Lu (61.71 to 143.46) confirm these higher ratios in SS09 and lower in SS01. The REE in the study area comes from hydrothermal processes based on high lineament densities at sampling points in igneous rocks with a mean ∑REE value of between 174-219 ppm.

Objective: The knowledge, attitudes, and practices of SUA students about the use of plastics containing endocrine disruptors were investigated in this study. Methodology: A study with 150 participants was conducted to assess individuals' knowledge about endocrine disruptors, attitudes, and plastic use practices. Results: The findings indicate that the participants possessed an average degree of knowledge 50.2 ± 3.85 with the main emphasis of awareness being generic concepts rather than specific substances. Regarding the potential health impacts of endocrine-disrupting chemicals present in plastics, respondents' attitudes ranged from fair to positive, with a mean score of 3.5 ±0.09 indicating a fair attitude overall. Conclusion: It is important to practice polite behavior and increase public awareness of safe plastic disposal methods. Surprising only 38.0% of the participants mentioned that they refrain from heating their food in plastic containers to reduce their exposure to plastics. Students' practices revealed a notable dependence on plastic products despite their awareness of the concerns surrounding endocrine disruptors, as most of them reported using plastic water bottles, plastic cups, and plastic bags almost always. Additionally, only 20.7% of the respondents consistently implemented strategies to prevent exposure to endocrine-disrupting chemicals. Recommendation: The study recommended increasing the use of cleaner plastic substitutes and improving educational programs to convert information into practical actions. Policies that encourage environmentally friendly behavior and raise public awareness of safe plastic disposal techniques should be put into practice.

Foods rich in phytochemicals are well recognized for their role in the prevention of chronic disease development, in addition to fulfilling the nutrient requirements. However, different processing methods employed during preparation may affect their levels and functionality as they are sensitive to different processing parameters such as temperature and light. This study aimed to evaluate the effects of three common processing methods; boiling, fermentation, and drying (sun and solar drying, with and without blanching), on total phenolic content and total flavonoid content in cassava (Manhot esculenta Crantz), black jack (Bidens pilosa) and bitter lettuce leaves (Launaea cornuta) grown in Mkuranga District in the Eastern part of Tanzania. Total phenolic content and total flavonoid content were analyzed by using the spectrophotometric method with the use of Folin-Ciocalteu and Aluminum Chloride reagents, respectively. Total phenolic content ranged from 0.9±0.14 to 85.7 ± 0.56 mg Gallic Acid Equivalent (GAE)/100g and flavonoids ranged from 0.03±0.00 to 3.9±0.03 mg/100g across the treatments. Both parameters were adversely affected by fermentation and boiling, while solar and sun drying only reduced the flavonoid content. Results showed that direct solar and sun drying appear to be effective processing methods, for the retention and maintenance of total phenolic content in all samples while, none proved to be effective for flavonoid content.

A diagnosis of the current state of the crops is made regarding the control of weeds, use of pesticides, fungicides; with an assessment of the state of the plant covers in the crop, and its control by different types of herbicides, and we detected a high loss of biological diversity; and some of these compounds are mentioned due to their high toxicity. Similarly, the use of pesticides and fungicides is discussed due to their repercussions on health. In order to avoid the unhealthiness caused by the applications of these products, phytosanitary and educational control strategies are proposed; promoting the inspection of fruit and vegetable markets, and modifying the contents in higher professional and university education. To this end, we propose an active teaching methodology, through which the student acquires skills and responsibility for the use of chemical agents in agriculture, which serves to prevent the entry of these contaminants into the food chain. Of the different polluting chemical agents, in the case of herbicides we highlight Oxyfluorfen and Glyphosate with high toxicity and whose consumption is very high. In the case of pesticides and fungicides, among others are Organochlorine compounds, which have been detected in blood, and Carbon Tetrachloride and Chloroform, considered potent hepatotoxic and neurotoxic. The basic objective of this study is the awareness and acquisition of knowledge by future teachers about polluting agents, which will subsequently have an impact on society.