life cycle assessments

• • a life cycle assessment is a method to examine environmental impact of a product
• the process is:

  • raw material extraction
  • manufacturing
  • use and reuse
  • maintenance
  • recycle and disposal
• raw materials:

  • extracting raw materials can damage environment through mining or quarrying
  • using raw materials can use up limited resources like crude oil
• manufacturing:

  • manufacturing can use up land for factories
  • some waste products can be reused, reducing pollution
  • some waste can cause alot of pollution
• use and reuse:

  • some use of products can pollute environment
  • how long a product is used and how many uses it gets
• recycle and disposal:

  • some waste can use up land for landfill sites
  • energy used to transport waste to landfill which can pollute environment
  • products may be burnt which can cause pollution
• plastic bags:

  • raw materials - crude oil, finite resource
  • manufacturing - fractional distillation and polymerisation, long process
  • use - can be reused, can be used for other things
  • disposal - recyclable but not biodegradable but will take up space in landfill
• paper bags:

  • raw materials - recycled paper or trees
  • manufactuing - expensive to glue handles on
  • use - only used once
  • disposal - biodegradable, non-toxic and can be recycled
• disadvantages:

  • it is hard to find a numerical value for effects of pollutants
  • producing LCA is not objective as it can take into account value of person carrying out assessment
  • LCAs can be biased
  • selective LCAs will only show some impacts on environment, to give positive advertising