Waste production and management can pollute air, water and soil, increase greenhouse gas emissions, damage biodiversity and harm human health. These impacts are often unequal, creating environmental justice concerns when disadvantaged communities bear harms caused by waste generated elsewhere.
This is IB ESS Subtopic 7.3, Solid waste, taught at both SL and HL. Waste arises when societies extract, process, consume and discard natural resources. Pollution occurs when harmful substances enter an environment faster than they can be degraded or transformed into harmless substances.
| Waste stage or method | Environmental impacts | Social impacts |
|---|---|---|
| Production and consumption | Resource depletion, habitat loss, energy use and greenhouse gas emissions | Unsafe working conditions and unequal resource access |
| Landfill | Land occupation, leachate contamination, methane emissions and wildlife disturbance | Odours, pests, reduced property values and nearby health risks |
| Incineration | Carbon dioxide emissions and toxic pollutants; energy recovery may displace fossil fuels | Respiratory risks if controls fail and local opposition |
| Recycling | Reduces virgin material demand and landfill, but transport and processing use energy | Creates jobs, while informal workers may face hazards |
| Waste export | Transfers pollution and ecological damage elsewhere | Receiving communities may bear health and economic costs for others' waste |
A named example is the Agbogbloshie electronic-waste site in Accra, Ghana, where informal processing and burning of imported and domestic electronics exposed workers and residents to hazardous smoke and contaminated soil. It shows that impacts may occur far from consumers.
A common misconception is that recycling makes waste harmless. It usually reduces impacts but still requires energy and processing. Under the waste hierarchy, prevention through refusing, reducing and reusing is generally more sustainable than recycling, treatment or clean-up.
Exam technique: For “evaluate”, weigh environmental and social benefits against costs, use a named example, compare stakeholder perspectives and finish with a supported judgement. Treat the full waste system.