As Hikemore mentioned, the whole question of drinking chemcically polluted affected water largely depends on where you are and where your intended wilderness activities will take place.

In the areas I adventure in, there is no cause for concern of drinking such polluted water. Yes there is a concern for other natural water borne hazards which is why I use the Aquatabs to treat the water.

Boiling is always an option (and a last resort for me) if you are carrying a stove or alternatively, able to light a small fire and have the time to boil the water. Keep in mind that on a long hot summer day hike, how much water 2 or more people will require. Plenty of years of personal experience has shown that these water requirements can be measured in gallons per day. Whereas using tablets, the water can be treated on the move, meaning that we refill the water bottles as we go and add an Aquatab to each bottle. After 30 minutes, the water is ready to be used and there is no delay for having to stop and boil water.

In a true wilderness survival situation, I would rather allow tablets to treat my water while my focus and energy is directed to other concerns in order to keep myself and possibly others, alive.