The effect of soil types, pH, and geographical locations on carcinogenic metal buildup in Oryza sativa cultivated in Ghana.

This study investigated the impact of soil type, pH, and geographical locations on the accumulation of arsenic (As), lead (Pb), and cadmium (Cd) in rice grains cultivated in Ghana. One hundred rice farms for the sampling of rice grains and soil were selected from two regions in Ghana-Volta and Oti. The concentrations of As, Pb, and Cd were analyzed using ICP-OES. Speciation modeling and multivariate statistics were employed to ascertain the relations among measured parameters. The results showed significant variations in soil-As, Pb, and Cd levels across different soil types and pH ranges, with the highest soil-As and Cd found in alkaline vertisols. For soil-As and Cd, the vertisols with a pH more than 7.0 exhibited the highest mean concentration of As (2.51 ± 0.932 mgkg-1) and Cd (1.00 ± 0.244 mgkg-1) whereas for soil-Pb, the luvisols of soil types with a pH less than 6.0 exhibited the highest mean concentration of Pb (4.91 ± 1.540 mgkg-1). Grain As, Pb, and Cd also varied across soil types and pH levels. In regards to grain-As, the vertisols soil type, with a pH less than 6.0, shows the highest mean concentration of grain As, at 0.238 ± 0.107 mgkg-1. Furthermore, vertisols soil types with a pH level less than 6.0 showed the highest mean concentration of grain Cd, averaging at 0.231 ± 0.068 mgkg-1 while luvisols, with a pH less than 6.0, exhibited the highest mean concentration of grain Pb at 0.713 ± 0.099 mgkg-1. Speciation modeling indicated increased bioavailability of grains Cd2+ and Pb2+ ions in acidic conditions. A significant interaction was found between soil-Cd and pH, affecting grain-As uptake. The average concentrations of soil As, Pb, and Cd aligned with international standards. Generally, the carcinogenic metals detected in grain samples collected from the Volta region are higher than that of the Oti region but the differences are insignificant, and this may be attributed to geographical differences and anthropogenic activities. About 51% of the study area showed a hazard risk associated with grain metal levels, although, no carcinogenic risks were recognized. This study highlights the complex soil-plant interactions governing metal bioaccumulation and emphasizes the need for tailored strategies to minimize metal transfer into grains.

Evaluation of hand hygiene behaviour in basic schools in Ghana: a case study of the Ablekuma Central Municipality in the greater region of Ghana.

Hand washing is effective for the prevention and transmission of pathogens but washing with water only is not effective at reducing contamination. The study focussed on the evaluation of hand washing behaviour in Basic schools (Primary and Junior High Schools) in Ghana. Results of the study revealed that 75% of responding schools have hand washing stands to promote hand washing with soap. Sixty percent of the hand washing facilities were functional at the time of the study in the schools. Hand washing facilities were found to be inadequate as most of the schools lacked running water and soap for hand washing. The school children (72%) were found to have knowledge on hand hygiene. The school children were aware that they can get cholera, typhoid fever, dysentery, diarrhoea, stomach cramps and pains when they do not wash their hands with soap. Majority (68.2%) of school children reported that washing hands after defecation is important but only 17.5% reported actually follow this practice. The school children (51%) reported washing their hands before eating. Many of the schools did not have toilet facilities for the school children. The school children (35%) learnt hand washing from their parents and 60% from the teachers.

Total coliforms, arsenic and cadmium exposure through drinking water in the Western Region of Ghana: application of multivariate statistical technique to groundwater quality.

In recent times, surface water resource in the Western Region of Ghana has been found to be inadequate in supply and polluted by various anthropogenic activities. As a result of these problems, the demand for groundwater by the human populations in the peri-urban communities for domestic, municipal and irrigation purposes has increased without prior knowledge of its water quality. Water samples were collected from 14 public hand-dug wells during the rainy season in 2013 and investigated for total coliforms, Escherichia coli, mercury (Hg), arsenic (As), cadmium (Cd) and physicochemical parameters. Multivariate statistical analysis of the dataset and a linear stoichiometric plot of major ions were applied to group the water samples and to identify the main factors and sources of contamination. Hierarchal cluster analysis revealed four clusters from the hydrochemical variables (R-mode) and three clusters in the case of water samples (Q-mode) after z score standardization. Principal component analysis after a varimax rotation of the dataset indicated that the four factors extracted explained 93.3 % of the total variance, which highlighted salinity, toxic elements and hardness pollution as the dominant factors affecting groundwater quality. Cation exchange, mineral dissolution and silicate weathering influenced groundwater quality. The ranking order of major ions was Na(+) > Ca(2+) > K(+) > Mg(2+) and Cl(-) > SO4 (2-) > HCO3 (-). Based on piper plot and the hydrogeology of the study area, sodium chloride (86 %), sodium hydrogen carbonate and sodium carbonate (14 %) water types were identified. Although E. coli were absent in the water samples, 36 % of the wells contained total coliforms (Enterobacter species) which exceeded the WHO guidelines limit of zero colony-forming unit (CFU)/100 mL of drinking water. With the exception of Hg, the concentration of As and Cd in 79 and 43 % of the water samples exceeded the WHO guideline limits of 10 and 3 µg/L for drinking water, respectively. Reported values in some areas in Nigeria, Malaysia and USA indicated that the maximum concentration of Cd was low and As was high in this study. Health risk assessment of Cd, As and Hg based on average daily dose, hazard quotient and cancer risk was determined. In conclusion, multiple natural processes and anthropogenic activities from non-point sources contributed significantly to groundwater salinization, hardness, toxic element and microbiological contamination of the study area. The outcome of this study can be used as a baseline data to prioritize areas for future sustainable development of public wells.

The hydrochemistry of groundwater in the Densu River Basin, Ghana.

Hydrochemical analyses of groundwater samples were used to establish the hydrochemistry of groundwater in the Densu River Basin. The groundwater was weakly acidic, moderately mineralized, fresh to brackish with conductivity ranging from of 96.6 microS cm(-1) in the North to 10,070 microS cm( - 1) in the South. Densu River basin have special economic significance, representing the countries greatest hydrostructure with freshwater. Chemical constituents are generally low in the North and high in the South. The order of relative abundance of major cations in the groundwater is Na+>Ca2+>Mg2+>K+ while that of anions is Cl->HCO3->SO4(2-)>NO3-. Four main chemical water types were delineated in the Basin. These include Ca-Mg-HCO3, Mg-Ca-Cl, Na-Cl, and mixed waters in which neither a particular cation nor anion dominates. Silicate weathering and ion exchange are probably the main processes through which major ions enter the groundwater system. Anthropogenic activities were found to have greatly impacted negatively on the quality of the groundwater.

The hydrochemistry of groundwater in rural communities within the Tema District, Ghana.

A detailed study has been carried out on groundwater in rural communities in the Tema District of the Greater Accra region of Ghana to establish the hydrochemistry and identify the various sources of contaminants as well assess the physical and chemical quality of the groundwater to ascertain their wholesomeness and the health impacts of the groundwater on the communities. The groundwater was found to vary considerably in terms of chemical and physical properties. Generally, the water was mildly acidic (pH 4.3-7.4), brackish to fresh, and undersaturated with respect to gypsum and halite. The majority of groundwater clustered toward Ca-Mg-SO(4) and Na-Cl facies. About 70% of boreholes sampled have elevated levels of NO(3)(-) -N, Cl(-), and SO(4)(2-) emanating from anthropogenic activities.