Human health risk assessment of exposure to cadmium, lead and chromium through consumption of well and bottled water in Lusaka district, Zambia.

Master of Science in Food Safety and Risk Analysis (FSRA)Water is an essential product for human survival, which all age groups consume and access to safe drinking water is essential to health. Safe drinking water implies that the water does not represent any significant risk to health over a lifetime of consumption, including different sensitivities that may occur between life stages. Water is prone to contamination with heavy metals through natural and anthropogenic pollution, making it unsuitable for human consumption because of the negative health outcomes associated with it. This study assessed the non-carcinogenic and carcinogenic risk of human exposure to cadmium, lead and chromium through consumption of well and bottled water in Lusaka district of Zambia. This study was a deterministic human health risk assessment that followed the Codex Alimentarius Commission's food safety risk assessment framework, comprising hazard identification, hazard characterisation, exposure assessment and risk characterisation. The objective was to assess the risk of exposure to cadmium, lead and chromium through water consumption. The study used results by Nambeye (2017) on well water quality analysis in George compound of Lusaka district and results by ZCSA (2021) on bottled water quality analysis in Lusaka district to estimate the non-carcinogenic and carcinogenic risk of exposure to cadmium, lead and chromium through consumption of well and bottled water. The high levels of cadmium, lead and chromium observed in these studies prompted the conduct of this exposure risk assessment study. The study adopted the World Health Organisation (WHO) and the United States Environmental Protection Agency (USEPA) default water consumption and exposure reference values to calculate the hazard quotient and cancer risk for the metals under study. This study found that the hazard index for cadmium, lead and chromium in both well and bottled water was higher than 1, indicating an adverse effect on human health, over a lifetime of consumption. Similarly, the total cancer risk through exposure to cadmium and chromium in well and bottled water was 1.2 x 10-1 and 2.25 x 10-1, respectively and higher than the safe threshold limit set by USEPA of 1 × 10−4. This study has concluded that there is a possible non-carcinogenic risk of exposure to cadmium, lead and chromium through consumption of bottled water in Lusaka district. The study also concluded that there is a possible non-carcinogenic risk of exposure to cadmium, lead and chromium through consumption of well water in George compound of Lusaka district. This is attributed to the high concentration of heavy metals in both well and bottled water. Results also indicate that there is a possible carcinogenic risk of exposure to cadmium and chromium through consumption of both well and bottled water, with a chance of causing 1 case of cancer for every 10,000 people for those who consume well water and 2 cases of cancer for every 10,000 people for those who consume bottled water, over a lifetime of water consumption. Owing to the proportion of samples that exceeded the Zambia Bureau of Standards threshold limit in both well and bottled water, cadmium poses the greatest concern and requires intervention to reduce exposure. Therefore, there is a need for relevant institutions to continue monitoring the levels of heavy metals in drinking water to protect the public from exposure to unacceptable levels of heavy metals

Markets and Gender Interaction in Climate Change Adaptation and Mitigation: A Case of the Coastal Kenya Sedentary Farm Households’ Experiences

Climate change is a global concern which manifests on a multilevel perspective and sometimes distinct or nested within some geographical boundaries. At the sedentary farm household systems climate change is real and continues to have impacts across different agro-ecological zones. A participatory rapid appraisal survey aimed at investigating the role of markets and gender participation in climate change adaptation and mitigation was conducted using key-informant interviews and gender-based group discussions in Kwale County of the coastal lowlands of Kenya. Results indicated that there has been an enormous and an elicited rapid reduction of vegetation cover by 50% in the last ten years, a 45-50% decline in cattle and 30% sheep and goat populations. The loss in vegetation cover and diversity, translated to a rapid increase in soil erosion mainly from wind and running water. Critical to farm sedentary households was the shift in the seasonal calendar characterized by erratic nature of rains in intensity and spatial distribution. Markets played a crucial role in factor-product mobility where some of the factors and/or products were drivers for technology marketing and adoption as a way of adapting to and mitigating climate change. Market forces were also instrumental in increasing the demand for energy thereby leading to increased vegetation harvesting for fuel wood and charcoal. Compared to the last 15 to 20 years, markets were major sources cereal-based food resources by over 80% as demonstrated by the movement of such resources from urban markets to the rural farm households other than the reverse. Markets also enhanced technology transfer and adoption by over 30% among households. There were however radical shifts in gender roles within households such as men sourcing for water in the event of severe or prolonged drought, women participation in the construction sector and increased social networks that with increased women participation in business. Ethnic based frameworks for gender roles were generally on decline following collapsing of cultural pillars which in the past dictated gender roles. The paper further outlines and suggests critical impacts of climate change across some identified vulnerable systems and makes policy recommendations to deal with the issues raised. Keywords: Climate change, markets, gender, sedentary farm households, adaptation and mitigatio

Resettling Displaced People in a Coastal Zone Mining Project: Evaluating the Agricultural and Land use Potential of the Proposed Resettlement site –A Case of Titanium Mining in Kenya

Preparations to mine titanium in Maumba and Noma areas of Msambweni District, Kwale County are in progress, and farmers affected by the project are to be resettled in another area. The displaced people have made it a condition that they should be settled in area where their farming activities are enhanced; and that adequate land is availed for social infrastructure. The identified site for resettlement site lies between latitudes 40 28’ and 40 32’ South, and between longitudes 390 16’ and 390 20’ East, and extends from Kiruku and Mwangwei to Kigombero. It receives an annual rainfall of 1,200-1,400 mm and is therefore suitable for rain-fed agriculture. About 75% of the land is low-lying and 50% of this is prone to flooding. Both communities are worried about the land allocation process, fearing about the quality and size of the land to be allocated to each, and the likely disintegration of existing socio-cultural structures. As good practise in integrated coastal zone management, the proposed resettlement site was evaluated to assess its suitability for crop and livestock production to sustain the livelihoods of the communities. The results of the evaluation show evidence of soil; the nitrogen, phosphorous, potassium, and organic carbon contents in the soils were generally low. To reverse the situation, inorganic and organic fertilizers should be used for crop and forage production to encourage build up of nutrient and organic matter levels in the soil. Drainage canals should be reconstructed to control flooding. Due to the low lying topography of the resettlement site, the portion on raised ground should be set aside for the homesteads. And other social infrastructure as demanded is be availed so that the communities continue with their life, despite the displacement. Key words: Titanium Mining, Displacement of Communities, Resettlemen