Chickasha, Okla. -- Chickasha residents say they have been drinking tainted water.
A letter was distributed by the city on October 18, 2014. Residents say it took a full year for the city to let them know their drinking water was compromised.
The normal level of in water supplies is not to exceed .08 but for twelve months the city of Chickasha averaged over .1 Trihalomethanes.
The letter lists the potential health problems from prolonged Trihalomethane exposure: "people who drink the contaminated water over many years` experience problems with their liver kidneys or central nervous system and may have an increased risk of getting cancer."
Trihalomethanes are a group of four chemicals that are formed along with other disinfection byproducts when chlorine or other disinfectants used to control microbial contaminants in drinking water react with naturally occurring organic and inorganic matter in water. The trihalomethanes are chloroform, bromodichloromethane, dibromochloromethane, and bromoform according to the EPA.
The city also detected Coliform Bacteria in water supplies. They say it's all caused by a valve failure.
According to the city, you don`t need to worry unless you have a child, you`re elderly or your immune system is compromised.
"I have a one year old daughter who I just filled her cup up with water this week at day care." said Chickasha business owner Keeley Taylor
She says she`s angry the city took so long to get the word out, and fears her daughter could suffer because of their mistake.
"My daughter has been having some pretty serious stomach issues and when I read this it just crossed my mind, I thought oh dear! As a mother I couldn`t help but think could it be from the water." said Taylor