Chloramine is a common disinfectant found in tap water, used by water utilities to ensure drinking water safety by inactivating disease-causing microorganisms. It’s intentionally added to maintain water quality throughout distribution systems.
Understanding Chloramine
Chloramine is a chemical compound formed when chlorine is combined with ammonia. Monochloramine (NHâ‚‚Cl) is the type primarily used in water disinfection. Water treatment facilities create chloramine by adding ammonia to chlorinated water, resulting in a stable disinfectant that helps control microbial growth.
Why Water Utilities Use Chloramine
Water utilities increasingly employ chloramine as a disinfectant due to its operational advantages over free chlorine. A primary reason for its adoption is its enhanced stability and persistence within water distribution systems. Unlike chlorine, which dissipates more quickly, chloramine maintains its disinfectant properties for longer periods, ensuring water remains safe as it travels through extensive pipe networks to consumers. This sustained disinfection is particularly beneficial for large or complex water systems.
Another significant factor driving the switch to chloramine is its effectiveness in reducing the formation of regulated disinfection byproducts (DBPs). When chlorine reacts with natural organic matter in water, it can form compounds like trihalomethanes (THMs) and haloacetic acids (HAAs), which are a health concern. Chloramine produces lower levels of these regulated DBPs compared to chlorine, helping utilities meet stricter federal drinking water regulations.
How Chloramine Affects Households and Health
For most individuals, water treated with chloramine is considered safe for drinking, cooking, and bathing, provided it meets regulatory standards. Some individuals may experience sensitivities, such as skin or respiratory irritation. The health concern for the general public from chloramine in drinking water is low.
Chloramine poses a significant risk to aquatic life because it can pass directly into their bloodstream through gills, damaging gills and impairing oxygen transport. Consequently, chloramine must be completely removed from water used in aquariums, ponds, and for amphibians or reptiles. Unlike chlorine, which dissipates when water sits, chloramine’s stability means it will not be removed this way.
Beyond biological impacts, chloramine can affect household plumbing and appliances, potentially degrading rubber and certain plastic components. It can also contribute to corrosion in some plumbing materials, such as copper pipes. For kidney dialysis patients, chloramine must be entirely removed from water used in dialysis machines because it enters the bloodstream directly; dialysis centers employ specialized filtration for this.
Removing Chloramine from Water
For consumers seeking to remove chloramine from their water, several methods are available. Activated carbon filtration is a widely used approach for reducing chloramine in household water. Catalytic activated carbon is highly effective, breaking down chloramine. Standard activated carbon can also remove chloramine, but it requires longer contact times and often a larger volume of carbon. These filters are found in pitcher filters, faucet-mounted systems, and whole-house filtration units.
For immediate removal, particularly for applications like aquariums or ponds, chemical dechlorinators are commonly used. Sodium thiosulfate is an example that rapidly neutralizes chloramine. These solutions are readily available at pet supply stores and make tap water safe for sensitive aquatic organisms.
Reverse osmosis (RO) systems represent a comprehensive water purification method. While the RO membrane itself does not directly remove chloramine, most RO systems incorporate pre-filters with activated carbon. The slow flow rate allows for extended contact time with these carbon filters, enabling effective chloramine reduction. This makes RO systems capable of removing chloramine, along with a broad spectrum of other contaminants.