AWWA JAW69180

Perchlorate is a contaminant of health concernbecause exposure to high levels over extended periodsmay adversely affect thyroid activity. In response torecent findings of perchlorate in sodium hypochlorite,NSF International surveyed sodium hypochlorite productsused to treat drinking water to better understandthe occurrence of perchlorate as a contaminant.Perchlorate contamination was found to occur in morethan 90% of sodium hypochlorite samples from productionfacilities across North America. Results also indicateda trend of increasing perchlorate concentration as thehypochlorite aged. The duration and conditions of storagecan affect the levels of the contaminant in a utilitys hypochloritesupplies and ultimately its drinking water.The investigation provided a basis for recommendationsto minimize perchlorate formation and lower thepotential for its unintended addition to drinking water.Sodium hypochlorite should be stored in the dark atcool temperatures, diluted if possible, and used withina few weeks of manufacture. Includes 10 references, tables, figures.



Keywords: Perchlorate; Sodium Hypochlorite; Water Contamination; Hypochlorites; Public Health