It's Biodegradable, Non-toxic and Natural, but is it Safe?

Companies make money selling their products; and the marketing departments in these companies are charged with making products stand out so that we’ll purchase them.  This usually involves throwing around buzzwords that will stick in our minds after we’ve heard them often enough.  “Non-toxic,” “natural,” and “biodegradable” are the marketing buzzwords meant to attract the attention of environmentally conscious consumers.  

What, exactly, though, do these words mean; and if something is non-toxic, biodegradable, or natural, does it mean that it’s safe?

Biodegradable refers to how readily something is decomposed in the environment, particularly by bacterial action.  There is a rather complicated, standardized test that is generally used to determine whether or not a chemical is biodegradable.  However, biodegradability really has little to do with whether or not something is toxic.  Just because something breaks down quickly in the environment does not necessarily mean that it is not toxic.  However, whether or not something is biodegradable gives you an indication of how long it might persist in the environment.  Theoretically, the longer something hangs around, the more likely someone (or some creature) will be exposed to it, and with the increased exposure, the chemical has more of a chance to do harm.  This is important for chemicals used outside or those that go into sewers or septic systems.  In these instances, it is preferable to use something that is biodegradable than something that is not.