A DPSIR and SAF Analysis of Water Insecurity in Lake Chad Basin, Central Africa

Abstract. Lake Chad is a transboundary freshwater body located in the extreme south of the Sahara Desert. Many centuries ago, the synergies between nature and human activities in the basin were in harmony; and nowadays, the manifestation of unsustainable human activities and drier climate in the basin is now evident. This study assesses the water insecurity and associated environmental issues in the area using the combined Driver-Pressure-State-Impact-Response (DPSIR) and System-Approach-Framework (SAF) frameworks. In achieving this, we conducted literature review to establish the major effects and possible consequences of water scarcity in the area. The SAF defines the Lake boundaries and eventually links the active stakeholders involved. On the other hand, the DPSIR reveals that about 90 % of inhabitants depends on agriculture, with warming (temperature) significantly increasing in the basin (0.22 ∘C per decade) – socio-economic and natural Drivers respectively – as well as increase in population. Pressures include input from irrigation systems, river–flow modification, limited rainfall, and prolonged drought periods. These pressures have led to change in the state of Lake Chad, like freshwater shortages and loss of ecological status. Impacts on human welfares includes mass displacement, unemployment, paralyzed socio-economic activities, and social unrest. The societal-Response has prompted various measures like the launch of campaigns and awareness, planned Inter-Basin-Water-Transfer (IBTW), and several policy changes for better governance. Conclusively, the restoration of Lake Chad solely depends on climate conditions and management policies. However, this study recommends the prioritization of monitoring systems, water-allocation plans, ecological plans, and modelling tools for better decision processes

Evaluating the potential health risk of organochlorine pesticides in selected protein foods from Abeokuta southwestern Nigeria

This study evaluated the potential health risk of OCPs in selected protein foods. A total of 66 food samples were collected from selected areas in Abeokuta, southwestern Nigeria. Food samples were analyzed for OCPs using the standard method. OCP data were analysed for descriptive and inferential statistics. Health risk assessment was conducted for non-carcinogenic {Hazard Quotient (HQ), Hazard Index (HI) and Cancer Risk (CR)}. The ΣOCP concentration was observed highest in pork (42.20 ± 33.33 mg kg−1) of which methoxychlor and dieldrin represented 63 and 28%, respectively. The HIs of OCPs in protein foods were generally greater than 1.0 indicating adverse effects. The ΣCR data showed carcinogenic effects in protein foods with values greater than the acceptable limit of 1.0 × 10−4