Life cycle assessments

Question 1

What do life cycle assessments look at ?

Answer 1

every stage of a products life to assess the impact it would have on the environment

Question 2

1) Getting the raw materials

Answer 2

Extracting raw materials needed for a product can damage the local environment and result in pollution due to the amount of energy needed

Raw materials often need to be processed to extract the desired materials and this often needs large amounts of energy .

Question 3

2 ) Manufacture and Packaging

Answer 3

Manufacturing products and Packaging can use a lot of energy resources and cause a lot of pollution.

Consider how to manage and dispose of waste products.

Chemical reactions used to make compounds from their raw materials can produce waste products . Some waste can be turned into other useful chemicals, thereby minimizing environmental pollution.

Question 4

3) Using the product

Answer 4

• can damage environment
  For example : burning fossil fuels releases green house gases and fertilisers can leach into rivers causing damage to ecosystems

How long a product is used for and how many uses it gets is also a factor - Products that need a lot of energy to produce but can be used for ages mean less waste in the long run

Question 5

4) Product disposal

Answer 5

Products are disposed in landfills, take up space and pollute land and water, example = paint washed off and end up in rivers

Energy used for transporting energy to landfill - causes pollutants to be released into atmosphere

Products might be incinerated which causes air pollution

Question 6

Life cycle assessment of plastic and paper bag and what it shows

Answer 6

raw materials = plastic bag, crude oil - paper bag, timber

Manufacturing and packaging = plastic bag ,Compound needed to make plastic from fractional distillation, cracking and polymerisation - Paper bag, pulped timber processed using a lot of energy and produces lots of waste.

Using the product = plastic bag , can be reused -
Paper bag, usually used once

Product disposal = plastic bag , Recyclable but not biodegradable and will end up in landfill, pollute land and take up space

Paper bag, Recyclable, biodegradable and non - toxic

Question 7

Problems with Life cycle assessments

Answer 7

1) use of energy, some natural resources and the amount of types of waste products by a product over its lifetime can be quantified, but, effect of some pollutants is harder to give a numerical value

2) Producing a LCA is not an objective method so takes into account values of person carrying out the assessment - can be biased

3) Selective LCA - only shows some of the impact of a product on environment - can be biased as written to deliberately support claims of company = give positive advertising