Toothbrush results interpretation

We only consider two points in this interpretation process : the answer to the main objective and the first investigation on environmental impacts.

Response to the main objective

Initial objective of the study : evaluate which brush has less environmental impacts.

According to the previous results, the manual toothbrush has less impact in four of the five categories evaluated. As far as climate change is concerned, the difference is too small to be conclusive.

Investigation of the impact source

Step-by-step iterative approach

The graph below details the stages in an iterative approach to investigating the sources of impacts

Impacts on the life cycle of an electric toothbrush

The graph below shows the main contributors to the cost of electric toothbrushes.

The ‘Toothbrush’ and ‘Brushhead’ categories cover the materials, manufacturing processes and transport required for each.

The manufacture of the brush is significant in all impact categories. It is even the main source of contribution in four of the five categories (except freshwater ecotoxicity): between 46% and 98%.

The end-of-life phase is a significant contributor (54%) to the freshwater ecotoxicity category.

The use phase, although less impactful, is also significant for three of the five impact categories (around 20-30%).

The ‘Toothbrush’ and ‘Brushhead’ categories cover the materials, manufacturing processes and transport required for each.

Brush body (%)

Brush head (%)

Use (%)

End of life (%)

Climate change

46,30%

19,04%

23,23%

11,43%

Human toxicity, cancer effects

69,32%

7,64%

21,62%

1,41%

Freshwater eutrophication

89,23%

2,36%

8,30%

0,11%

Freshwater ecotoxicity

27,76%

0,33%

17,91%

54,00%

Mineral, fossil & ren resource depletion

97,21%

0,14%

2,64%

0,01%

Sensibility and evaluation of the data quality

The interpretation phase is used to compare the assumptions made throughout the LCA.

It is necessary to assess the quality of the dataset used and the robustness of these assumptions, in particular through sensitivity analyses.