Twenty-first century human behaviour continues to escalate activities that result in environmental damage. This calls for environmentally friendly solutions, such as waste recycling and handling, to deal with the increased amount of waste, especially plastics. The plastic materials manufacturing sector is booming, particularly packaging; while only a fraction of its waste is recycled, another fraction is destroyed, and the larger part continues to pollute the environment. In addition to other waste disposal activities, destroying plastic or incineration (which could be for energy recovery) is usually subjected to strict legal requirements because of its effect on the environment. However plastic is destroyed or disposed of, it poses a serious challenge in both the short term and the long term to humans and their natural environment if the process is not efficiently managed. This article describes how a growing amount of plastic waste is disposed of haphazardly in South African townships, while most of the inhabitants are not aware or do not care about the adverse environmental and health effects of these actions. This article examines the environmental and health effects of poor plastic disposal in South African townships as it is in other developing countries to sensitise the citizens to the significance of reducing plastic waste quantities, which will downplay their impact on human health and the environment.

The increasing concern about the environment has led to the necessity of ensuring efficient Construction and Demolition Waste Management (C&DWM) in the built environment. Despite the extensive research on C&DWM, the industry still faces significant challenges, including inefficiencies, high costs, and environmental impacts. Meanwhile, incorporating digital technologies (DTs) has emerged as a way to eradicate the challenges of C&DW. In response to the knowledge gap, in this research, we conducted a systematic literature review (SLR), incorporating bibliometric, text-mining, and content analysis to meet the research objectives. In total, 126 papers were retrieved from the Scopus database and transferred into VOSviewer to conduct the bibliometric analysis. The findings identified seven specific DTs, namely, blockchain, Internet of Things (IoT), Artificial Intelligence (AI), Machine Learning (ML), Robotics, Computer Vision (CV), and Building Information modeling (BIM). This study demonstrates that these technologies play a significant role in promoting efficient C&DWM in the construction industry. The study’s implication lies in its potential to guide industry stakeholders and policymakers in promoting the use of DTs and overcoming the barriers to their adoption, thereby facilitating more efficient and sustainable C&DWM practices. Finally, the findings of our research indicate possible future research directions for promoting DTs for C&DWM and eradicating the barriers to efficient implementation.

The discovery of plastic by humankind is fast becoming a challenge as the end-of-life disposal of plastic continues to be a discourse on the global platform. This discussion results from several findings that the additives in plastic distress both land and marine life by contributing to organic pollutants when the plastic waste is disposed of improperly. With a growing population in sub-Saharan Africa, managing waste generally, and plastic waste, in particular, represents a continuous challenge. With only between 15–25% of its plastic waste recycled, the larger proportion of waste is either burnt openly or disposed of in open spaces or landfills, where the additives pollute the environment. Moreover, some of the waste finds its way into waterways through estuaries into global water networks and continues to cause harm to man through the food chain. This article examines the literature to highlight the environmental and health impact of plastic waste pollution in sub-Saharan Africa, and it proposes mitigation strategies to reduce the critical consequences of plastic waste pollution.

Effective materials management on construction sites is handled carelessly by construction practitioners. This may result in several challenges such as materials waste generation, poor quality of work, project delays, and poor materials flow. Construction practitioners in Abuja, Nigeria, do not understand the consequences of these challenges to construction projects. This article investigates the effect of poor materials management on materials waste, quality of work, and project profitability in construction projects in Nigeria. A qualitative research approach was adopted in the study which included collective case study investigations. The population for the study was ongoing building project sites (ten case studies purposefully selected) in Abuja. The research instrument was direct-covert observation by the researchers to observe and record the construction processes, people’s behaviour, actions and interactions relating to materials management. The construction processes observed included materials usage onsite, loading/offloading of materials from procurement, storages, as well as materials handling and movement on site. Recording sheets with checklists were pre-set with statements (Likert items) and responses to observe and document the effect of poor materials management. The statements were rated on an ordinal three-point Likert scale. The observed/collected data were analysed using descriptive methods to determine the modal values. The findings from the study revealed that poor materials management has a considerable effect on material waste generation on any construction project site; moderate effects on quality of building projects, and both considerable and moderate effects on profitability in the construction projects. Based on these findings, it can be concluded that effective management of materials in construction projects would reduce the amount of waste generation, increase the quality of construction work, and offer optimum profitability to construction contractors. It is, therefore, recommended that the construction industry in Nigeria should collaborate with government agencies to develop guidelines for preparing a waste management plan for the construction industry.

The total amount of cost overruns for any construction project can be fully determined once the project is completed. Estimating the amount of cost overruns at different stages of ongoing construction projects is important for project success. There is, however, a dearth of research for this exercise. This article reports the results of an investigative study on cost overruns for ongoing building projects in Abuja. The quantitative technique was adopted in this study. The investigation included ongoing building-construction projects within Abuja, from which a sample of 30 building projects (public and private) was purposively selected (project value of ZAR100 million and above). The data were sourced from the archival records (drawings, bills of quantities, project progress reports, and specifications) on the issues relating to the costs and duration of building projects. The data were analysed using descriptive (percentages) and inferential methods. The results revealed that the percentage of cost overruns ranged from a minimum of 5.56% with 90% project completion, and within 88% of the estimated time limit, to a maximum of 216.08% with merely 5% project completion, and within 8.3% of the estimated time limit. The entire projects had average cost overruns of 44.46%, with an average project completion of 52.4%, and within 91.4% of the average estimated time limit. Based on these findings, it can be concluded that continuous investigation into, and analyses of cost overruns at stages of building projects would encourage professionals to apply the best mitigation measures, in order to achieve a significant reduction in the total cost overrun at the completion of a project. Construction professionals should be well informed of these consequences (cost overruns) at an early stage, in order to evaluate the extent to which these consequences could be minimised.

Material wastage on construction sites can contribute to cost overruns. Research to provide evidence of the extent of material wastages’ contribution to cost overruns on construction sites is based mostly on surveys. Thus, the actual contribution is not yet ascertained. The purpose of this article is to report the results of an objectively investigated study on the contributions of material waste to project-cost overrun. The methodological approach adopted for the study is the quantitative technique that is rooted in the positivist paradigm. The investigation included ongoing building construction projects within Abuja, Nigeria, from which a sample of 31 public and private projects was purposefully selected (project value of ?1.6 billion Naira and above). The data for this research were sourced from the field investigation (measurement of the volume of material waste) and data from the archival records (drawings, bills of quantities, project-progress reports, and specifications) on material waste and cost overruns. The collected data were analysed using the Pearson moment correlation and the descriptive method. The research results revealed a statistically significant relationship between material waste and cost overrun. This implies that any increase in the volume of material waste would lead to a corresponding increase in the amount of cost overrun. The results showed that the significant percentage contribution of material waste to project-cost overrun ranges from 1.96% to 8.01%, with an average contribution of 4.0% to project-cost overruns. It is recommended that construction professionals be well informed of the consequences of material waste contributions to project-cost overrun at an early stage, in order to enable the professionals to evaluate the extent to which these consequences could be minimised.