Know Your Environment. Protect Your Health.

Bromate

Portland Water District - Greater Portland

Bromate is a carcinogenic disinfection byproduct formed when source waters containing bromide are treated with ozonation or sodium hypochlorite. Studies of laboratory animals show that bromate damages DNA and causes cancer in multiple organs. Click here to read more about disinfection byproducts.

 

24

Samples

0

Samples exceeding legal limit (MCL)

1

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2018ND40ND
2019ND40ND
2020ND40ND
2021ND40ND
2022ND40ND
20230.250 ppb41ND - 1.000 ppb

ppb = parts per billion

State, National, and Health Guidelines for Drinking Water

EWG Health Guideline: 0.1 ppb

The EWG Health Guideline of 0.1 ppb for bromate was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.

EPA Maximum Contaminant
Level (MCL): 10 ppb

The legal limit for bromate, established in 1998, was based on analytical detection limits at the time that the standard was set. This limit may not fully protect against the risk of cancer due to bromate exposure.

ppb = parts per billion

All test results

Date Lab ID Result
2018-03-15201803190437ND
2018-06-04201806050721ND
2018-09-10201809110289ND
2018-12-10201812110285ND
2019-03-04201903050329ND
2019-06-03201906040408ND
2019-09-03W-190903-0038ND
2019-12-09201912100147ND
2020-03-24202003250223ND
2020-06-15202006160103ND
2020-09-22202009230292ND
2020-12-15202012160207ND
2021-03-22202103230191ND
2021-06-09202106100694ND
2021-09-14202109150693ND
2021-12-06202112081038ND
2022-03-15202203161115ND
2022-06-15380-4452-1ND
2022-09-13810-38162-1ND
2022-12-06380-30473-1ND
2023-03-21380-41192-1ND
2023-06-06380-50130-1ND
2023-09-14380-63088-11.000 ppb
2023-12-14380-75250-1ND