Lead and cadmium lead to kidney failure in children and lead poisoning in adults, according to a new study published in the journal Environmental Science & Technology.
The study, which surveyed more than 5,000 people, found that the lead and cadmeas lead in water is three times higher than the level in drinking water.
The lead is present in the form of lead paint, paint thinner, and lead solder.
The cadmias cadmites can also form as a byproduct of industrial processes.
Lead poisoning can be life-threatening, especially in older adults and children.
Exposure can cause blood poisoning, kidney failure, brain damage, or death.
Cadmium can cause a condition called “cerebral hyperperfusion” in which the brain becomes abnormally dense and hard.
The University of Colorado, Boulder, said in a news release the lead levels in drinking-water samples “are at or near levels of concern.”
The university said the lead was found in water samples collected from homes in Denver, Boulder and Larimer counties.
The lead level was 3,500 times higher in Denver and 1,300 times higher for Boulder County.
Ceres Lead, the company that makes lead paint in the state, said it had conducted testing on water samples from residents in Denver in the spring and summer.
The company said the water tested positive for cadmite contamination, which is a form of the toxic chemical lead.
Lead can cause problems with the kidneys and nervous system, and can lead to a range of neurological disorders, including Alzheimer’s disease, Parkinson’s disease and multiple sclerosis.