1. C3 Chemicals in Our Lives – Risks & Benefits Lesson 11: PVC

2. Objectives MUST explain that PVC is polymer of carbon, hydrogen and chlorine SHOULD explain why plasticisers in some types of PVC may be harmful

3. Key Words You need to be able to define the following: ◦ PVC ◦ Plasticisers ◦ Leaching

4. Textbook Answers 1)Plasticised PVC – electrical insulation; any use of sheet PVC; fake leather. uPVC – construction-related uses: e.g. pipes, gutters, window frames. 2)It is soft and flexible. 3)If the baby sucks on the toy the plasticiser can be leached/washed out of the material by saliva and swallowed. 4)Tests on lab rats and from fish. 5)Pollution from the manufacturing process; fumes from fires; leaching of plasticisers. 6)PVC has a high risk because of the answers to question 5; plasticised PVC should be banned because of the risk from plasticisers; alternatively the many uses of PVC make it too valuable a material to be banned.

5. Worksheet Answers Activity 1 (Low demand) 1)a) Strong/ hardwearing/ tough; b) an insulator/ flexible; c) soft/ flexible/ water resistant; d) tough/ hardwearing/ can be shaped easily. 2)a) 3; b) Contains chlorine as well as carbon and hydrogen. c) (i) Lots of polymer molecules close together; (ii) Polymer molecules spaced out by smaller molecules. Activity 2 (Standard demand) 1)Look for points for and against the use of PVC cling film, quality of sources, opinions based on evidence. 2)Plasticiser washed out clothes etc. when washed; carried to sewage works; then into watercourses and absorbed by fish.

6. Worksheet Answers Activity 3 (High demand) 1)Tests to show how much plasticiser is leached from the polymer; tests (on animals) to find the effects of the plasticiser; epidemiological surveys to find a link between children using the toys and suffering from poor health. 2)Report should provide evidence for both sides and list any sources used; a limited ban may be justified; a more general ban will await alternatives to PVC that do the jobs more safely.