1)- That's fine.
2) I'd take out 'enough' and say 'I don't theink they are effective'. I'd change 'overtaken' to something like 'sidelined by the drive for short-term profit'
3) Change 'propoganda' to 'publicity'? It should be 'environmentally friendly'. Change the verbs in the last to 'wastes' and 'adds'.
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