My knee-jerk reply was "no", but...
Betadine® is a brand name for a product line that includes products with detergents. See
http://woundcare.org/newsvol2n2/ar1.htm Quoting: "Betadine Microbicides contain a complex of the polymer polyvinylpyrrolidone with iodine (PVP-I) which, after application, continues to deliver iodine over a period of time."
As you noted, some people use povidine iodine for water purification, with one of the better references over at high-altitude medicine:
http://www.high-altitude-medicine.com/water.html#Backer1995I think there are two questions to ask:
1) Does the suggested 4 drops / liter (clear water) disinfect water to drinking standards? (Pete... if you have the time to test this, it would be great to know the answer). Note that most agree that it takes very very long contact times for all halogens, specifically iodine, to destroy oocystic organisms like giardia and crypto; they work best as anti-bacterial, anti-viral, and anti-fungal agents.
2) Are there any significant health hazards from ingesting the trace amounts of other (admitably USP grade) chemicals used in Betadine®? (My GUESS is these are insignificant / begnign, but I'm not an expert on those matters).
I have used iodine (Tetraglycine hydroperiodide; US military and PA) for decades and trust it. But now my wife has a very mild thyroid condition, so I'm considering switching to a different disinfectant for water purification. AFAIK, there are not really any great substitutes for PVP-I when it comes to wound cleansing, but I'm looking.
I know this doesn't give you a definitive answer - I don't believe there is a consensus. Good question.
Tom