Nearly 300 wells across the state of California are said to contain harmful chemicals ordinarily found in furniture , clothing , packaging and fire - retardants . There are some important caveats to this data. The chemicals , known broadly as PFOS or PFOA , have been linked to cancer , developmental issues in children and damage to the liver and immune system . The announcement was made following the legislation requiring the testing of 600 " at - risk " wells . There is no agreement upon safe level of these chemicals . Consumers have been warned , however , some water from the contaminated wells is mixed with other sources before reaching taps . It 's also possible water is contaminated before delivery .
Nearly 300 wells across the state of California are said to contain harmful chemicals ordinarily found in furniture , clothing , packaging and fire - retardants . The chemicals , known broadly as PFOS or PFOA , have been linked to cancer , developmental issues in children and damage to the liver and immune system . The announcement was made following the legislation requiring the testing of 600 " at - risk " wells . There is no agreement upon safe level of these chemicals . Consumers have been warned , however , some water from the contaminated wells is mixed with other sources before reaching taps . It 's also possible water is contaminated before delivery .