Pollution may be caused by natural sources or human activities, but regardless of the cause, the result is the same. It can have detrimental effects on aquatic ecosystems as well as the health of those who depend on those sources of water, like us!
review verb (THINK AGAIN) C1 [ T ] to think or talk about something again, in order to make changes to it or to make a decision about it: The committee is reviewing the current arrangement/situation. Let's review what has happened so far.
REVIEW, practice. A second examination of a matter. For example, by the laws of Pennsylvania, the courts having jurisdiction of the subject may grant an order for a view of a proposed road; the viewers make a report, which when confirmed by the court would authorize the laying out of the same.