Answer:
This might be a bit technical but the power point could be named "common externalities as a market failure: air and water pollution".
Explanation:
An externality occurs when a third party suffers the negative (or postive) consequences of an economic transaction between two other parties.
Air and water pollution are externalities because it affects everyone who live or use the air and water that is polluted, whether they participate in the economic activites that created the pollution or not.
For this reason, externalities like pollution, are considered market failures.