This paper presents a comparative review of arsenite (As(III)), arsenate (As(V)), and fluoride (F − ) for a better understanding of the conditions and factors during their adsorption with focus on (i) the isotherm adsorption models, (ii) effects of pH, (iii) effects of ionic strength, and (iv) effects of coexisting substances such as anions, cations, and natural organics matter. It provides an indepth analysis of various methods of arsenite (As(III)), arsenate (As(V)), and fluoride (F − ) removal by adsorption and the anions' characteristics during the adsorption process. The surface area of the adsorbents does not contribute to the adsorption capacity of these anions but rather a combination of other physical and chemical properties. The adsorption capacity for the anions depends on the combination of all the factors: pH, ionic strength, coexisting substances, pore volume and particles size, surface modification, pretreatment of the adsorbents, and so forth. Extreme higher adsorption capacity can be obtained by the modification of the adsorbents. In general, pH has a greater influence on adsorption capacity at large, since it affects the ionic strength, coexisting anions such as bicarbonate, sulfate, and silica, the surface charges of the adsorbents, and the ionic species which can be present in the solution.

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The appalling state of Liberia's municipal solid waste management system (MSWM) is the motivation for this review and analysis. Solid waste management protocols and system dynamic modeling support policy development as it uses waste prevention to explain the complex waste management systems and suggests methods for effective management. However, creating an effective waste system goes beyond the formulation of policies and legislation; it involves financial and technological proficiency, skilled human capacity, technical, social, resource recycling, educational awareness programs, and active public participation. Because of urbanization, Liberia's municipal solid waste (MSW) problems have become heightened, thereby impacting the economic, social, and political fabric of society by overburdening infrastructure and social facilities. The impact of urbanization must be addressed because urbanization, amongst several factors, including unsustainable management of MSW, degrades the environment and presents risks to public health. The purpose of this review was to highlight the current waste management activities in Liberia and provide information to the readers about the challenges facing the waste management sector and the challenges impeding the development of a sustainable waste management system. In Liberia, waste management activities are getting worse daily due to shortage of a comprehensive waste management framework, the absence of guidelines regarding the responsibilities of waste generators, and the decision-makers' lack of intent to design and implement a sustainable and integrated management system. Recommendations for collaborative efforts are made by focusing on delivering a waste strategy which concentrates on waste minimization, recycling, resource recovery, and promoting sustainable waste management practices for communities, small businesses, corporations, and government institutions in Liberia and other developing countries.

The ineffective management of household solid waste (HSW) in most developing cities in Africa including Monrovia has become a major issue threatening the environment and public health. In response to these waste challenges, developed countries have embarked upon major environmental reforms, and have made advances in best practices and sustainable management of their Municipal Solid Waste (MSW). However, in most developing countries like Liberia, such environmental reforms have not been initiated and therefore the situation has become compounded; this is due to several factors impeding the development of a sustainable municipal solid waste system. This study, therefore, aims to critically analyze the influencing factors of solid waste management; the characteristics of household waste and suggest management solutions for effective and sustainable management.<br/> Results from the analysis of data, using The Ordinary Least Square Regression (OLS) method estimates the average household waste per capita generation as 0.76kg/capita/day. Regarding the composition of the waste stream, the results show that 67% of the waste sampled from Monrovia is biodegradable and mostly comprised of high wet weight and high moisture content kitchen waste. On the other hand, the remaining percentage is mostly non-degradable but recyclable materials such as glass ceramics and metals. This suggests that due to the high moisture content in the waste, samples are suitable for composting and other mechanical and biological management options. Using the stratified sampling method, 300 households were chosen. Multiple regressions were conducted to determine the relationship between waste generation and socio-economic factors and these showed that the effect of income, household size and the environmental concern on HSW generation is statistically significant at a 1% significance. However, further findings revealed a negative relationship between income and HSW generation at a 1% level of significance. These findings provide new insight regarding the role of socio-economic characteristics affecting the generation of household waste in Monrovia.

Healthcare waste management continues to present an array of challenges for developing countries, and Liberia is of no exception. There is insufficient information available regarding the generation, handling, and disposal of health care waste. This face serves as an impediment to healthcare management schemes. The specific objective of this study is to present an evaluation of the current health care management practices in Liberia. It also presented procedures, techniques used, methods of handling, transportation, and disposal methods of wastes as well as the quantity and composition of health care waste. This study was conducted as an investigative case study, covering three different health care facilities; a hospital, a health center, and a clinic in Monrovia, Montserrado County. The average waste generation was found to be 0-7kg per day at the clinic and health center and 8-15kg per/day at the hospital. The composition of the waste includes hazardous and non-hazardous waste i.e. plastic, papers, sharps, and pathological elements etc. Nevertheless, the investigation showed that the healthcare waste generated by the surveyed healthcare facilities were not properly handled because of insufficient guidelines for separate collection, and classification, and adequate methods for storage and proper disposal of generated wastes. This therefore indicates that there is a need for improvement within the healthcare waste management system to improve the existing situation.