Water purification may be necessary in back country camping, travel to areas without clean water or disaster situations. According to the OA Guide to Water Purification, 90 percent of the world’s water contains some type of contaminants, including viruses and other microorganisms. Ingesting these contaminants can cause diarrhea and vomiting, which are serious conditions when the lost fluids cannot be easily replaced.
When to Use Iodine
Iodine treatment of water can be used in any situation where you do not have ready access to clean water, including camping or natural disasters that have disturbed or cut off the clean water supply. In these situations, the Environmental Protection Agency advises that you purify the water you use to drink, cook and brush your teeth to avoid any chance of ingesting contaminants.
Forms of Iodine
Iodine for purifying water comes in tablet, crystal and liquid forms. While the amount of iodine recommended per liter of water differs depending on the iodine product, the EPA generally recommends 5 drops of iodine per liter or 10 drops per liter if the water is cloudy, and 1 iodine tablet per liter if you do not have access to product instructions.
Effectiveness of Iodine Treatment
According to the OA Guide, iodine and other types of water treatments kill microorganisms but do not remove toxic chemicals like pesticide runoff and other types of pollution. The effectiveness of iodine tablets also depends on the water temperature and the age of the tablets, since an open package of iodine tablets expires after a certain amount of time. Always read the directions on iodine water purification products to ensure that you treat the water correctly.
In order for iodine treatment to work, the water needs to sit for at least 30 minutes with the chemical added, explains the EPA. Make sure the tablet has fully dissolved, and then wait an additional 30 minutes for the iodine to treat the water. The OA Guide also suggests that you treat cold water for twice as long as warm water, since the iodine treatment disperses slower in cold water. You can heat water on a stove or warm a bottle of water in the sun before adding iodine treatment to maximize the effectiveness.
Cloudy water requires more iodine treatment than clear water. The EPA advises that water with visible particles be strained through a cloth before purifying. Iodine treatment may affect the taste of the water, and you can decrease the iodine taste by pouring the water back and forth between two containers to mix it up, adding a little salt or adding flavored powder.
Warnings and Considerations
Some people are allergic to iodine. Pregnant women, women over 50 and people with thyroid problems should consult their doctors before using iodine treatment for water purification.
Alternatives to Iodine
Alternatives to iodine tablets include chlorine treatment or a water filtration system. If you have access to a stove, you may want to simply boil the water for 1 minute and let it cool before drinking, as suggested by the Centers for Disease Control and Prevention.All of these alternative water purification methods are safe for people who have iodine allergies. The EPA recommends that if you are in a disaster situation and do not have access to iodine tablets, you use medical iodine from a first aid kit or a small amount of household chlorine bleach to purify the water.