Collaboration with Durham University, Heriot-Watt University, Liverpool School of Tropical Medicine, University of Dar es Salaam, University of Malawi and University of Strathclyde.
The overarching aim of the SPACES project will be to focus on the sources, economic & behavioural drivers of plastic pollution in densely populated cities in Tanzania (who have just enforced a ban on plastic bags) and Malawi (who have just rejected a ban on plastic bags) in order to influence policy and directly deliver societal impact by incentivising behavioural change. Discarded plastic in the peri-urban environment is a serious challenge for sustainable waste management and for the delivery of environmental & public health. In many cities in sub-Saharan Africa, plastic wastes, and plastic bags in particular, block urban drainage systems. During rain events this leads to localised flooding, with an increased risk of human exposure to raw sewage and the spread of waterborne pathogens within highly populated areas. Plastic waste can also act as a transient receptacle for rainwater and thus provide a larval habitat for mosquitoes. Specifically, we will quantify the impacts of plastic pollution on human health in terms of blocked drainage, increased frequency and magnitude of flooding and the subsequent spread of pathogens such as cholera and typhoid, and the provision of transient receptacles for breeding mosquitoes. In parallel, issues associated with reduced air quality from burning plastics, contamination of food grown in urban areas, and the mental health and well-being consequences of living with significant levels of environmental plastic pollution will also be determined. Plastics in soil and water may also be acting as a reservoir for pathogenic microbes, e.g. diarrheagenic bacteria, particularly if they have been in contact with a source of faecal contamination. In addition to direct human exposure risks, the persistence and transfer of microbial pathogens from these reservoirs could be facilitated by heavy rain and resulting runoff, or as a consequence of scavenging domestic and wild animals. In turn, urban plastics may also play an important role in facilitating the survival of bacteria carrying AMR genes and facilitating the emergence of novel zoonotic diseases. Urban and peri-urban farmers in sub-Saharan Africa commonly produce perishable crops such as leafy vegetables for sale in local markets, which is crucial for providing a continual supply of vitamin-rich vegetables to urban communities. However, the impact of growing vegetables in urban soils contaminated by plastics, and irrigating them with waste water contaminated by microplastics is not clear; therefore, the SPACES project will quantify the risk of microplastic ingestion, but also the risk of those microplastics being colonised by human pathogenic microbes, e.g. typhoid. The wider mental health and well-being implications of people living with plastic waste will be explored within the frameworks of 'blue health' and 'green health', by testing the hypothesis that people living in heavily polluted areas have become blind to plastic waste in their environment. However, the choices people have for disposing of their plastic waste are limited, despite having significant implications for human health. Thus, this interdisciplinary project aims to understand local perceptions, in terms of community health, of plastic waste in the environment, and the diversity in decision-making processes behind plastic disposal. There are currently two choices for people living in informal settlements and slum environments, (1) to dump their plastic waste in the environment, or (2) to burn their plastic waste. Burning plastic produces toxins that can adversely affect the person doing the burning, but also more widely can have an impact of the air quality for the local community. The effects of these two options on community health will be quantified against a backdrop of developing alternative choices such as increased plastic re-use and the incentives needed for localised recycling (e.g. tax breaks for existing recycling companies, or by providing start-up resources for entrepreneurial SMEs). Quantitative and qualitative mixed methods approaches will be developed to understand what socio-economic and political obstacles exist for incentivising governments to remove peri-urban plastic waste and increase sustainable waste disposal. Novel strategies for intervention, mitigation and sustainable adaptation by local communities, will be co-developed with extensive use of behavioural economics and anthropological methods in tandem with environmental, biological, epidemiological and geographical approaches. Working with a range of local recycling associations and local government and council leaders, the SPACES project will provide both the evidence, and incentives that will allow individuals, communities, business leaders and national decision-makers to foster a sustained change in attitudes for tackling the challenges of plastic waste in the environment, in turn delivering a step change towards enabling a cleaner, more resilient and productive environment.