120THIS MANUAL MAY BE SOLD AT COST ONLY - AND IS NOT TO BE OFFERED FOR RESALE.Usually elemental iodine can’t be tasted below 1 PPM,and below 2 PPM the taste isn’t objectionable. Iodineions have an even higher taste threshold of 5 PPM.Note that removing the iodine taste does not reducethe dose of iodine ingested by the body.Sources of Iodine:Tincture of Iodine:USP tincture of iodine contains 2%iodine and 2.4% sodium iodide dissolved in 50% ethylalcohol. For water purification use, the sodium iodidehas no purification effect, but contributes to the totaliodine dose. Thus it is not a preferred source of iodine,but can be used if other sources are not available. 0.4cc’s (or 8 drops) of USP tincture (2% iodine) added toa liter of water will give the 8 mg/l (same as 8 PPM).If the iodine tincture isn’t compounded to USP specs,then you will have to calculate an equal dose based onthe iodine concentration.Lugol’s solution:Contains 5% iodine and 10%potassium iodide. 0.15 cc (3 drops) can be added perliter of water, but 3 times more iodine is consumedcompared to sources without iodide.Betadyne(povidone iodine): Some haverecommended 8 drops of 10% povidone iodine perliter of water as a water treatment method, claimingthat at low concentrations povidone iodine can beregarded as a solution of iodine. One study indicatedthat at 1:10,000 dilution (2 drops/liter), there was 2PPM iodine, while another study resulted in conflictingresults. However, at 8 drops/liter, there is little doubtthat there is an antimicrobial effect. The manufacturerhasn’t spent the money on testing this product againstEPA standard tests, but in other countries it has beensold for use infield water treatment.Kahn-Vassher solution:By adding a sufficientamount of iodine crystals to a small bottle, an almostunlimited supply of saturated iodine solution can beproduced. As long as crystals remain in the bottle,the solution is saturated. Concentration of the iodineis dependent of temperature, either condition atambient temperature can be assumed, or commercialmodels such as Polar Pure incorporate a liquid crystalthermometer to determine dose.One criticism of this method is the chance of decantingiodine crystals into the water being treated. This isn’tthat much of a problem as iodine is very weakly toxic,but the Polar Pure incorporates a collar into the neck ofthe bottle to help prevent this. Another disadvantage tothis method is that the saturated iodine solution must bekept in glass bottles, and is subject to freezing, but this ishardly an insurmountable problem. Freezing, of course,doesn’t affect the crystals.
