From Wikipedia, the free encyclopedia. Phototoxicity, also called photoirritation, is a chemically induced skin irritation, requiring light, that does not involve the immune system. It is a type of photosensitivity. The skin response resembles an exaggerated sunburn.
The contribution margin ratio is the difference between a company's sales and variable expenses, expressed as a percentage. The total margin generated by an entity represents the total earnings available to pay for fixed expenses and generate a profit.
Definition: Variable contribution margin is the margin that results when variable production costs are subtracted from revenue. It is most useful for making incremental pricing decisions where an entity must cover its variable costs, though not necessarily all of its fixed costs.