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.
a critical article or report, as in a periodical, on a book, play, recital, or the like; critique; evaluation. the process of going over a subject again in study or recitation in order to fix it in the memory or summarize the facts.