♻ Life Cycle Assessments (LCAs)

🔹 What is an LCA?

  • An LCA tries to measure the environmental impact of a product.

  • Looks at 4 main stages:

    1. Extracting & processing raw materials

    2. Manufacturing, packaging & transport

    3. Use during lifetime

    4. Disposal at end of life

🔹 Environmental Impact Examples

  1. Raw materials

    • Plastics → crude oil extraction, refining, cracking → energy intensive, fossil fuels burned → climate change.

    • Metals → ores mined, transported, extracted → large energy use & toxic waste.

  2. Manufacturing/packaging/transport

    • Energy required.

    • Harmful waste released.

  3. Use during lifetime

    • E.g. toys may need lots of batteries → toxic waste from battery production.

  4. Disposal

    • Transport to landfill/recycling uses energy.

    • Many products contain harmful chemicals needing careful disposal.

🔹 Case Study: Plastic vs Paper Bags

Plastic bags

  • Made from crude oil (non-renewable).

  • Oil extraction → habitat damage (e.g. leaks).

  • Strong & often reused (e.g. bin liners).

  • Lightweight → lower transport energy.

  • Problem: Non-biodegradable → persistent litter, fill landfills.

Paper bags

  • Made from wood (renewable, but deforestation damages habitats).

  • Manufacturing needs large energy + lots of water.

  • Weak → often single use.

  • Heavier → higher transport energy.

  • Biodegradable (breaks down when wet).

🔹 Problems with LCAs

  • Some impacts measurable: water use, energy, some wastes.

  • Others hard to judge: actual environmental damage → often estimates/ value judgments.

  • Risk of bias (e.g. advertisers presenting products as “greener”).