Effects of Effluent from a Dumpsite on the Physicochemical Properties of River Achichum in Bamendakwe, Northwest Cameroon

This study was aimed to assess the effects of effluent from a dumpsite on the physicochemical properties of river Achichum in Bamendakwe in the Bamenda I municipality, Northwest Region of Cameroon. The quality of water used for domestic purposes by the population of this area is mostly appreciated through its organoleptic assessment while no attention is paid to the physicochemical and microbiological properties. Samples (upstream, effluent, and downstream) were collected in the months of September 2022 and February 2023 and examined for organoleptic, physicochemical and bacteriological characteristics using standard methods. The river was contaminated to different extents by nitrates (28.56 - 149.91 mg/L), sulphates (246.89 - 725.42 mg/L) and heavy metals (0.01 - 0.04 mg/L for lead and 0.98 - 2.15 mg/L for aluminum). This contamination could be due to an inflow of the untreated effluent into the river. The river contained a high pollution level of lead and aluminum. Bacteriological investigations revealed that all the analyzed samples from the river contained indicators of faecal pollution such as Enterobacteria spp., E. coli, Streptococcus spp., Salmonella spp., Shigella spp., Staphylococcus spp. and Vibrio spp. Consequently, its utilization exposes consumers to health risks. Thus, water from the river should be treated prior to consumption.

Determination of the Toxicological Risk of Urban Waste from the City of Uvira Dumped into the North-Western Coast in Lake Tanganyika (Democratic Republic of Congo)

This study focuses on determining the toxicological risks of urban waste from the city of Uvira, discharged into Lake Tanganyika, on the surrounding population. Volatile organic compounds were measured in a variety of solid waste matrices, including inorganic micropollutants in wastewater and fish. The concentrations of Hg and Pb in the lake were found to be 1.21 and 1.42 μg/L respectively and between 0.83 to 18.36 μg/L of Hg and 8.25 to 670 μg/L of Pb, at the collector outlet. The presence of trace metallic elements, such as Cr, Co, Ni, Cu, Zn, As, Sb, Hg and Pb, were detected at high concentrations compared to the WHO standard. An ecotoxicology experiment herein on wastewater samples showed lethal pollutant concentrations of the order of 0.0055 mL/mL which killed at least 50% of fish (LC50), confirming the toxicity of the wastewater. These potentially harmful effluents also contain volatile organic compounds originating in high concentration from the pharmaceutical discharges of the general Uvira hospital, in particular: toluene, ethylbenzene, m-xylene/p-xylene, o-xylene and chloroform in higher concentrations compared to the norm. Other components such as benzene, bromodichloroethane and 1,1-dichloroethane were found to be present, but at a concentration below 0.05 ppb. A variety of trace organics can be suspected to be present as well.

Analysis of Pesticide Residues in Some Market Garden Crops in Santa, North West Cameroon

The increased use of pesticides in crop production, especially in Santa, has left consumers with great fear and uncertainty regarding the fate of residues after consumption in the human body. This study was aimed at performing a multi-residue analysis of crop samples to detect and quantify pesticide residues present, and thus determine their level of contamination. Twelve (12) crop samples (4 samples each of Solanum tuberosum (Irish potato), Solanum lycopersicum (tomato), Capsicum annum (sweet pepper) and Apium graveolens (celery)), were randomly collected from four villages in Santa. The samples were analyzed using the QuEChERS Buffered AOAC 2007.01 method. The results showed the presence of pesticide residues in 58.3% of the samples. Cypermethrin and chlorpyrifos insecticides were detected, though cypermethrin was found in traces. After quantification, the concentration of chlorpyrifos was determined to be far above the CODEX Maximum Residue Limits (MRLs) in 28.6% of the samples. Samples with this high concentration of chlorpyrifos were: tomato from Pinyin and Baligham (2.0 and 1.8 μg/g respectively), whereas the Codex MRLs for tomato is 1.0 μg/g. This study raised concerns on the contamination of some garden crops by pesticide residues and calls for the assessment of the health situation of consumers and the analysis of pesticide residues in drinking water resources in this area.

Assessment of Ground Water Quality in Baba I Village, North-West Cameroon

This study investigated the quality of ground water in Baba I, North-West Cameroon, in order to determine its suitability for domestic uses following World Health Organisation (WHO) guidelines. Inhabitants of this locality consume water from these sources without any prior treatment which can lead to health problems if the water sources are contaminated. Six water sources were sampled in November 2017, January, April and July 2018 and examined for organoleptic, physico-chemical and bacteriological parameters using standard methods. Results of organoleptic and physical parameters showed that most of the sources were within the WHO acceptable limits with pH varying from moderately acidic to weakly basic. Chemical properties revealed that all the analysed ions were found within the WHO guidelines and the water sources ranged from soft (hardness +, K+, Ca2+, Mg2+, NO3-? and NH4+??(p Escherichia coli, Enterobacter, Streptococcus, Salmonella and Shigella spp, were identified in all the sampled waters, suggesting recent contamination of the sources by human or animal faeces. The sources were unfit for domestic uses and thus, exposed the local population to water borne diseases such as typhoid, diarrhoea and dysentery. Hence, home treatment methods such as chlorination, filtration, boiling and solar disinfection should be implemented prior to consumption.