Is boiling enough

[Ali]

From my research all the bugs and bacteria are actually killed off around the 79 to 84 degrees. They only tell you to reach boiling point as a visable check, plus water actually boils slightly before/after 100 degrees depending on your height to sea level. So boiling for longer than say 20 seconds is pointless, just to make sure it is a boil and not just bubbles.
Further purification is not needed, but its is worth pointing out that boiling does not remove chemicals.