Disinfection by-products

In most cases, water must be disinfected to inactivate or kill microbial pathogens. However, disinfectants can react with naturally occurring materials in the water to form byproducts including trihalomethanes (THMs), haloacetic acids (HAAs), chlorite, chlorate, and bromate.  Some disinfection byproducts (DBPs) are health concerns. 

The problem is so pervasive that the US EPA has developed the Disinfectants and Disinfection Byproducts Rules (DBPRs) to monitor and limit exposure to these disinfectant byproducts. 

To reduce exposure to disinfectants and their by-products, water systems use permanganate as a recognized alternative oxidant for use at the water plant.  Permanganate can oxidize DPB precursors, reducing hazardous byproduct formation when disinfectants are applied. 

The use of permanganate will also provide iron and manganese oxidation, taste and odor control, and cyanotoxin reduction. Permanganate oxidation alone has been shown to reduce byproduct formation by as much as 5-40%.  A water plant in California was able to reduce their THMs by over 70% by moving the pre-chlorine from the flash mix to the filter water and adding CAIROX® potassium permanganate to the raw water as a pre-oxidant. Read our DBPs case study, here. 

Jar testing can determine the optimum dosage of permanganate needed for your water. Typical permanganate dosages are 0.5 mg/L to 2.0 mg/L.