Society's marginal cost of pollution abatement curve slopes upward because of the law of diminishing marginal utility.

Marginal Cost

The financial outlay required to produce a further unit of a product or service.

Pollution Abatement

Actions taken to reduce, control, or eliminate pollution from sources in order to protect the environment.

Marginal Utility

The supplementary utility or enjoyment obtained by consuming an additional unit of a good or service.