EWG's Tap Water Database — 2021 UPDATE


Monochlorobenzene (chlorobenzene)

Palm Lake Estates South

Monochlorobenzene is used as a solvent for pesticides, a degreasing agent and an intermediate for manufacturing other chemicals. It causes liver and kidney damage in studies of laboratory animals.





Samples exceeding legal limit (MCL)


Samples exceeding
health guidelines

Testing results - average by year

YearAverage resultSamples takenDetectionsRange of results
20150.787 ppb165ND - 5.91 ppb
20161.32 ppb227ND - 8.64 ppb
20190.158 ppb220.0654 ppb - 0.250 ppb

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 70 ppb

The EWG Health Guideline of 70 ppb for monochlorobenzene 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 harm to internal organs.

EPA Maximum Contaminant
Level (MCL) 100 ppb

The legal limit for monochlorobenzene, established in 1991, was based on a toxicity study in laboratory animals conducted in the 1960s.

ppb = parts per billion

All test results

Date Result