Chloramine, and Health: What Is Known – Confusion and Clarity

1. Chloramine, and Health: What Is Known – Confusion and Clarity Jeffrey K. Griffiths, MD MPH&TM Professor of Public Health, Tufts Univ. Chair, US EPA Drinking Water Committee

2. Some history • Chloramines have been used as a secondary disinfectant since the early 1900s (>90 years). During WWII, ammonia was needed for the war effort (explosives) so many utilities switched to chlorine from chloramine. • > 20% of US citizens drink water treated with chloramines. Treatment Plant Filter & Disinfect Pipes – the Distribution System SOURCE WATER

3. Chlorine • Water has to be disinfected or else we get infections from the water system. Chlorine was the first disinfectant with wide use ~ 1900 • Chlorine not only kills microbes, it reacts with organic matter in water and creates disinfection byproducts (DBPs) which cause bladder cancer. There are strong suggestions (but not proof) that DBPs can cause fetal nervous system problems, and miscarriages. • Led to changes in drinking water standards.

4. Why use chloramine? • Chloramine leads to much less formation of DBPs with a different spectrum than chlorine. It should thus cause less cancer. • It is less reactive than chlorine, yet remains active in water for a longer period of time. These two factors “balance out” for disinfection (around longer, less reactive = similar result). • Chloramine – technically monochloramine – has little if any adverse taste or smell.

5. Chlorine versus Chloramine • Top arrow: chlorine inactivated, no power to kill microbes at end of water delivery pipe. Cancer-causing DBPs increase over time. • Bottom arrow: chloramine still present, killing microbes at end of water delivery pipe

6. Mono, di, and tri-chloramine • Chloramine results from the combination of chlorine and ammonia. If you use a lot of ammonia, you get monochloramine. • HOCl plus NH3 = NH2Cl and H2O • If you use a little ammonia and a lot of chlorine, you get dichloramine & trichloramine. Trichloramine is the “chlorine smell” at swimming pool – often a lot of chlorine is added and a little ammonia is present (pee).

7. pH and Monochloramine • If the pH of water is above 7 (neutral) then you naturally have monochloramine – the “chloramine” as used by water industry • If pH is lower, get bi- and tri-chloramines. • Drinking water is pH adjusted.

8. Health impacts monochloramine • There is no evidence of skin problems because of monochloramines. Public health officials investigated in San Francisco and in Vermont where complaints were made – could find no evidence this was the case. • Chloramine-T (N-chloro tosylamide sodium salt) is a sulfonamide - not monochloramine. It is used to treat diseases in fish, and has been rarely reported to cause eczema.

9. Health impacts monochloramine • Chlorine and monochloramine can react with your blood if you are on hemodialysis. They can harm fish as they enter their blood through their gills. Chlorine or chloramine should be removed from dialysis water or aquarium water. • Trichloramine, not monochloramine, can irritate the lungs & cause asthma-like symptoms. • Monochloramine may allow more leaching of lead into water than chlorine if you have lead pipes.

10. Washington DC , Lead, and Chloramine • In Washington DC, use of chloramine dropped DBPs from 75 ppb to 40 ppb on average (good). • Water Authority did not optimize the use of orthophosphate, a corrosion inhibitor. Ortho-phosphate forms a protective coating inside pipes and decreases the leaching of lead. They were warned they had to pay attention to this but they did not pay attention. • Lower DBPs; high levels of lead in water (bad)

11. Once corrosion control in place, lead levels dropped in Wash. DC water Washington DC Water and Sewer Authority, Drinking Water Quality Report 1999-2006

12. Chloramine Summary • Does not: cause asthma; cause skin disease; cause cancer; harm plants or soil watered with it; have a nasty smell; make you lose your hair. • Does: lower cancer-causing DBPs (decreases it significantly); mobilize lead from lead solder or pipes more than chlorine unless lead corrosion control in place. • Unknowns: What residual risk exists from the DBPs which are made? (similar to chlorine where we still have unanswered questions)