RESUMO
Self-supply water has been acknowledged as a viable alternative to meeting the water needs of inhabitants. This study was designed to determine the main issues that influence self-supply water coverage in five (5) communities in the Kumasi Metropolis. The research employed a well-structured questionnaires and a total of 369 households were surveyed. The Statistical Package for Social Sciences (SPSS) version 26 and Microsoft Excel (2016) tools were used to analyse the data. The outcomes of the research show that a greater number of the respondents (77 %) did not have connections to the Ghana Water Company Limited (GWCL) distribution system. Approximately, 69 % of respondents had access to alternative water sources with mechanized boreholes forming the majority (32 %). However, a greater number of the respondents (64 %) did not disinfect their water to make it potable. The most favourable drinking water source for a greater number of the residents (51 %) was sachet water. The study showed there was a significant association between respondents' type or source of water with religion (p < 0.000), household size (p < 0.000), duration of stay (p = 0.026) and number of dependents (p = 0.006). However, there was no association between type or source of water with educational level (p = 0.130), occupation (p = 0.310), income level (p = 0.139) and type of home (p = 0.102). This study revealed that self-supply is contributing to the water needs of some residents in Kumasi and could contribute to the country's accomplishment of SDG 6.1 if residents ensure that it is safely managed. To broaden the scope of the study and the impact of self-supply groundwater, additional studies should be conducted in other communities, as well as the extent of other beneficiaries who have access to self-supply facilities other than the owners.
RESUMO
Waste picking is a pivotal in achieving sustainable waste management, environment health and economic development in the era of sustainable development. The study assessed the practices, knowledge, perception and health risk protection behaviours of waste scavengers in the Gbalahi landfill site. A total of 60 scavengers were conveniently sampled and interviewed. The study revealed that 93% of the waste scavengers sort waste using hooks and their bare hands. The study also showed 62% of the respondents have ever been physically abused by other scavengers. A good number of scavengers believed they have been fortified against "dirt diseases" during their childhood and have developed natural immunity against diseases. The knowledge of scavengers was skewed towards economic benefits as they viewed waste picking as a survival strategy. Discrimination and physical abuse posed a seemingly significant psychological health risk to majority of them. Safety and protection practices are limited to the use of pieces of clothes to cover the nose, wearing of multiple clothes and worn-out boots recovered from the landfill. Most of the respondents risk being exposed to the virus and pathogens. It is recommended that education and increased sensitisation should be encouraged and implemented by the Environmental Protection Agency (EPA), Ghana Health Service and other allied institutions in order to regularise and ensure the health and safety of waste scavengers.
RESUMO
BACKGROUND: Adsorption is a unique and promising method for the removal of trace metals from an aqueous environment using cost-effective and readily available biochars. OBJECTIVE: The present study examined mono and simultaneous adsorption of cadmium (Cd), mercury (Hg) and lead (Pb) onto biochars produced at pyrolysis temperatures of 350 ± 5°C and 700 ± 5°C. METHODS: Fifty mg/l of trace metal ions with 2 g/50 ml of adsorbent dosage were leached at constant room temperature of 24 ± 0.5°C in the laboratory with a constant contact time of 72 minutes. A total of 126 elutes were obtained from the batch experiments and conveyed to the Ecological Laboratory at University of Ghana for the analysis. RESULTS: In the mono-component system of Cd, Hg and Pb, removal efficiency was almost 100% using groundnut, shea nut shell, and a combination of groundnut and shea nut shell biochars. The experiment showed that shea nut shell biochars have the strongest affinity for trace metal ions in the mono aqueous phase. In the binary system, the removal efficiency was over 99.60% for cadmium and 100% for mercury. The ternary experiment showed an order of adsorption of Pb2+ > Hg2+ > Cd2+ for Cd, Hg and Pb ions onto groundnut and shea nut shells biochars. Fast pyrolysis temperatures and some types of biochar showed a slight increase in the adsorption efficiency of metal ions, but the increase was not statistically significant (p > 0.05). CONCLUSIONS: The study revealed that the Langmuir adsorption isotherm was the best fit model for trace metal ion adsorption onto biochars in the batch experiment. The interactive effects of binary and ternary metal systems onto biochars are antagonistic and synergistic in nature. Based on these results, it is recommended that further competitive adsorption studies of these biochars should be undertaken for accurate estimation of adsorption in natural environments. COMPETING INTERESTS: The authors declare no competing financial interests.
RESUMO
The study assessed levels of heavy metals in drinking water sources in two small-scale mining communities (Nangodi and Tinga) in northern Ghana. Seventy-two (72) water samples were collected from boreholes, hand dug wells, dug-out, and a stream in the two mining communities. The levels of mercury (Hg), arsenic (As), lead (Pb), zinc (Zn), and cadmium (Cd) were determined using an atomic absorption spectrophotometer (AAS). Mean levels (mg/l) of heavy metals in water samples from Nangodi and Tinga communities were 0.038 and 0.064 (Hg), 0.031 and 0.002 (As), 0.250 and 0.031 (Pb), 0.034 and 0.002 (Zn), and 0.534 and 0.023 (Cd), respectively, for each community. Generally, levels of Hg, As, Pb, Zn, and Cd in water from Nangodi exceeded the World Health Organisation (WHO) stipulated limits of 0.010 for Hg, As, and Pb, 3.0 for Zn and 0.003 for Cd for drinking water, and levels of Hg, Pb, and Cd recorded in Tinga, exceeded the stipulated WHO limits. Ingestion of water, containing elevated levels of Hg, As, and Cd by residents in these mining communities may pose significant health risks. Continuous monitoring of the quality of drinking water sources in these two communities is recommended.