The Role of Leather Microbes in Human Health

Leather tanned from raw hides and skins have been used to cover and protect the human body since early man. The skin of an animal carries thousands of microbes. Some are beneficial and protect the animal while others are pathogenic and cause diseases. Some microbes have no defined roles in animals. These microbes end up in the human body through contact with the animal skin. In recent years, the human body has been studied as an ecosystem where trillions of microorganisms live as a community called microbiome. Humans need beneficial microbes like Bacillus subtilis on the skin surface to stay healthy. Many microbes need the human body to survive. Not many studies have looked into the close link between animal leather and the human microbiome. The assumption is that conventional leather processes inhibit the pathogens on skins from carrying any risk of microbial hazard to the human body. This chapter identifies endemic microbes of “animal skin microbiome” that withstand extreme acidity and alkalinity of leather manufacture and their transmission to humans. Some cause allergic reactions, skin lesion, infections or death to tannery employees with weakened immune systems. This promotes the need to look at leather product microbiome impact on human health

Assessment of Heavy Metals in Landfill Leachate: A Case Study of Thohoyandou Landfill, Limpopo Province, South Africa

Landfilling of solid wastes has gained increasing acceptance due to the ease of disposal. However, such activity has consequences if the landfill site is not designed according to specification or does not have a leachate liner and collection system. Leachate possesses potential risk to surface and groundwater aquifer within the area surrounding the landfill site. The aim of this chapter is to assess the physicochemical parameters and heavy metal levels in leachate generated from a periurban landfill site situated in Thohoyandou, Limpopo Province, South Africa. Physicochemical parameters were measured onsite using standard methods, while heavy metals were analyzed with flame atomic absorption spectrometer (FAAS) after nitric acid digestion. pH, conductivity and turbidity values ranged from 6.97 to 7.68, 426 to 2288 μS/cm and 12.78 to 295.5 NTU, respectively. Most levels of the determined heavy metals exceeded the effluent discharge guideline limit of South African Department of Water Affairs. This could potentially spike their levels in surface and groundwater. Adequate measures should be put in place to manage the leachate generated from landfill sites

Impact of Wastewater on Surface Water Quality in Developing Countries: A Case Study of South Africa

Wastewater effluents are major contributors to a variety of water pollution problems. Most cities of developing countries generate on the average 30–70 mm3 of wastewater per person per year. Owing to lack of or improper wastewater treatment facilities, wastewater and its effluents are often discharged into surface water sources, which are receptacles for domestic and industrial wastes, resulting to pollution. The poor quality of wastewater effluents is responsible for the degradation of the receiving surface water body. Wastewater effluent should be treated efficiently to avert adverse health risk of the user of surface water resources and the aquatic ecosystem. The release of raw and improperly treated wastewater onto water courses has both short‐ and long‐term effects on the environment and human health. Hence, there should be proper enforcement of water and environmental laws to protect the health of inhabitants of both rural and urban communities. This study reports major factors responsible for the failing state of wastewater treatment facilities in developing countries, which includes poor operational state of wastewater infrastructure, design weaknesses, lack of expertise, corruption, insufficient funds allocated for wastewater treatment, overloaded capacities of existing facilities, and inefficient monitoring for compliance, among others

Household Hazardous Waste Management in Sub‐Saharan Africa

Household hazardous wastes (HHWs) have not been given serious attention in sub‐Saharan Africa. There is little or no information on HHWs in many developing countries of the world. This is regardless of the fact that they are very toxic and contain constituents which are persistent in nature. Once released into the environment, they can remain stable for exceptionally long periods of time. They have the potential to be harmful to public health and the environment if not handled, used, and disposed properly. This study reports the level of knowledge and management of HHWs in three tertiary institutions in sub‐Saharan Africa. Several factors were found to be responsible for poor management of HHWs. These include lack of awareness, inadequate treatment technologies, financial constraints, lack of realistic policies and legal frameworks, and unplanned settlements, among others

Health Risk Assessment of Heavy Metals on Primary School Learners from Dust and Soil within School Premises in Lagos State, Nigeria

This chapter is aimed at evaluating learner’s health risk based on the concentration of toxic metals (Pb, Cr, Cd and Mn) in soil/dust from playgrounds/classrooms in selected primary schools in Lagos State. Samples were divided into four groups based on the density of the locations. Concentration of toxic metals in samples were determined by Graphite Furnace Atomic Absorption Spectrophotometer (GFA-EX7) technique after microwave digestion. The result showed that some of the heavy metals in the soil were higher than permissible limits set by DPR, FEPA and WHO. The soil/dust were contaminated with Cr, Cd and Pb but Mn was within permissible limit. Due to exposure to playground soil and classroom dust, hazardous index (HI) for non-carcinogenic/carcinogenic risk in children was estimated. HI value indicated that the heavy metal pollution may pose no obvious non-cancer health risk to children learning in such schools. However, children via ingestion pathway are exposed to the greatest carcinogenic risk followed by the inhalation pathway. The cancer risk for learners was found to be 3.2 × 10−2 (1 in 31 individuals). Hence, there is need for local environmental authorities to be warned about the potential health risks caused by heavy metals in playground/classroom

Student’s Knowledge, Attitude, and Perception (KAP) to Solid Waste Management: A Survey towards a More Circular Economy from a Rural-Based Tertiary Institution in South Africa

Students of Higher Educational institutions (HEIs) are regarded as major stakeholders of an institution and key agents of transformation in society. Thus, the environmental knowledge of students in academic institutions is instrumental in providing a solution to the solid waste menace and other environmental problems in the community. However, there exists a wide rural–urban gap in transitioning towards sustainable development across HEIs. This informed the current study examining the knowledge, attitude, and perception (KAP) of students at a rural-based educational institution on solid waste management. It also aimed to learn about the institution’s current practices regarding solid waste management and identify steps that can be taken to move the institution closer to a circular economy goal. This study presents the KAP results from a survey of 376 students from nine schools at the University of Venda for the conceptualization of a circular economy (CE) vision for the university. The results show that the knowledge of the students on solid waste management was low and inadequate. However, students are willing to partake in recycling projects to improve the current environmental state of the institution. This study also revealed that some of the students (41%) require motivation to participate in recycling schemes through economic incentives. Increasing awareness of environmental education and initiating participatory environmental programs and strengthening 3 of the key sustainability competencies is recommended as an effective tool to transition to a circular economy in the institution. Further studies are recommended in areas of gamified learning for CE and capital generation from waste for capacity building

The application of synthesized geopolymer for the removal of cationic dye from industrial wastewater

In this study, a low-cost and effective coal fly ash porous geopolymer (CFPG) was prepared through alkali activation and applied as adsorbent for the removal of Rhodamine B (RhB) from real industrial wastewater. Mineral composition, microstructural analysis and surface chemistry were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, respectively. The batch experiment was investigated at different CFPG dose (0.4–2 g), RhB concentration (5–30 mg/L), pH (2, 7 and 10) and contact time (30–300 min). The removal efficiency for the adsorption of RhB using CFPG was affected by dosage, concentration, and time. However, removal efficiency of 100 % was achieved at pH (2, 7 and 10) indicating that the adsorbent can be used in wide pH range owing to the zwitterionic nature of RhB. The findings demonstrated that while increasing the initial dye concentration resulted in a decrease in removal efficiency, increasing the CFPG dose and contact time led to an improvement in removal efficiency. Additionally, for specified values of examined parameters, such as CFPG dose of 2 g, initial RhB dye concentration of 5 mg/L, and contact time of 300 min, the maximum efficiency of 100 % was achieved for RhB dye removal. The study on removal efficiency of CFPG on selective dyes showed that it could also be used to remove other cationic dyes such as malachite green and crystal violet in industrial wastewater as removal efficiency of 100 % was obtained for the removal of both dyes. Pseudo-first-order (R2 = 0.985) and Freundlich (R2 = 0.860) models were most suitable for the adsorption process

Student’s Knowledge, Attitude, and Perception (KAP) to Solid Waste Management: A Survey towards a More Circular Economy from a Rural-Based Tertiary Institution in South Africa

Students of Higher Educational institutions (HEIs) are regarded as major stakeholders of an institution and key agents of transformation in society. Thus, the environmental knowledge of students in academic institutions is instrumental in providing a solution to the solid waste menace and other environmental problems in the community. However, there exists a wide rural–urban gap in transitioning towards sustainable development across HEIs. This informed the current study examining the knowledge, attitude, and perception (KAP) of students at a rural-based educational institution on solid waste management. It also aimed to learn about the institution’s current practices regarding solid waste management and identify steps that can be taken to move the institution closer to a circular economy goal. This study presents the KAP results from a survey of 376 students from nine schools at the University of Venda for the conceptualization of a circular economy (CE) vision for the university. The results show that the knowledge of the students on solid waste management was low and inadequate. However, students are willing to partake in recycling projects to improve the current environmental state of the institution. This study also revealed that some of the students (41%) require motivation to participate in recycling schemes through economic incentives. Increasing awareness of environmental education and initiating participatory environmental programs and strengthening 3 of the key sustainability competencies is recommended as an effective tool to transition to a circular economy in the institution. Further studies are recommended in areas of gamified learning for CE and capital generation from waste for capacity building

Characterization of pulverized Marula seed husk and its potential for the sequestration of methylene blue from aqueous solution

Abstract Dyes are ranked as an important class of pollutants which affect the aesthetic property of the environment when present even in very low concentrations. This study was carried out to explore the potential use of an agricultural waste (Marula seed husk) to decontaminate methylene blue (MB) from aqueous solution. The effect of change in water chemistry was also examined. The influence of basic adsorption parameters such as contact time, temperature, dosage, pH and particle size on the efficiency of adsorption were investigated. Langmuir and Freundlich isotherms were used to describe the equilibrium data while Pseudo first, second order and Elovich kinetic models were used to evaluate the kinetics of the adsorption process. Thermodynamic parameters such as change in enthalpy (ΔH°), entropy (ΔS°) and Gibbs free energy (ΔG°) were evaluated. Natural surface water showed higher MB removal efficiency than de-ionized water. The sorption process was favored more in alkaline pH range (7–10). The dye adsorption process was found to be endothermic, while ΔG° was negative implying that the reaction is spontaneous. Functional group analyses on the adsorbent showed the presence of hydroxyl, carbonyl and carboxyl groups. The Langmuir equilibrium model best described the adsorption process based on the linearized coefficient. The Pseudo second order model best described the kinetics of the reaction

Sequestration of Congo Red from aqueous solution using raw and citric acid-modified Dicerocaryum eriocarpum biomass: isotherm, kinetics and thermodynamics

Abstract In recent times, dyes such as Congo Red have proven to be resilient environmental pollutants affecting freshwater portability among other media. Its toxicity to humans, animals and plant life is both a cause of concern and a motivation to prioritize decontamination. Many materials have been explored for the removal of this pollutant via adsorption; however, there are notable areas of improvement. Dicerocaryum eriocarpum (DE) seed is a non-toxic, cost-effective plant material which is possible as a sorbent and has not been reported in Congo Red sequestration. This research is therefore based on the removal of Congo Red dye from aqueous solution using raw (RDE) and citric acid-modified DE (CDE). The sorbents were characterized before and after sorption using various characterization techniques such as FTIR, EDS, SEM and BET. The effects of contact time, adsorbent dosage, concentration, pH and temperature were optimized during the experiment. According to experimental findings, modification with citric acid resulted in a reduction of the equilibration interval from 90 to 60 min. Sorption effectiveness increased with an increase in temperature for CDE but a decrease in temperature for RDE. The equilibrium data were best described by the Langmuir isotherm with maximum sorption capacity (q max) of 51.02 mg/g and 53.19 mg/g for RDE and CDE, respectively. Pseudo-second-order model better suited the kinetic data, while thermodynamic analysis revealed a spontaneous sorption process. Five cycles of desorption experiments using 0.1 M NaOH revealed that the regenerated sorbent effectively removed CR dye for the first three cycles at comparable efficiency to the virgin samples. This study therefore supports the use of DE seed as an easily accessible and efficient sorbent for remediation of harmful dyes from water