What are the symptoms of arsenic poisoning?

It starts with small bumps or warts. The warts may seem cosmetic, but they are a sign of a graver concern.

Discolorations of the skin can be caused by long-term arsenic exposure - the kind Churchill County residents have had for years.

Opinions differ on the health implications of naturally occurring arsenic, but the EPA has long advocated the least possible ingestion.

Mark Walker, a University of Nevada, Reno assistant professor, has researched arsenic in Churchill County well water for years. Last year, he compiled a sampling survey from about 350 homes and asked the families how they consume water. Walker said they found out a lot of people are consuming private well water with more than 10 ppb of arsenic.

"One of the things we've found is that people are trying to figure out if it is a big problem," he said. "Some people have lived there for a long time so they are less likely to be concerned. The newer you are to the issue, the more likely you are to consider it a problem. The longer you've been living there, the less you are concerned about it."

According to the Agency for Toxic Substances and Disease Registry Web site on arsenic, Americans are mostly exposed to higher-than-average levels of the metal in the workplace, near hazardous waste sites or in areas with high natural levels.

State Health Officer Dr. Brad Lee said the health problems associated with arsenic poisoning depend on duration and the type of exposure.

"It depends on the person with how much it takes to kill," he said. "And that's tons more than what's in the water."

He said the arsenic in Fallon's water has chronic cumulative effects, and the strongest association is with skin cancer. Warts appear on the palms, soles and torso. Darker spots can become cancerous. No one really knows why arsenic causes skin disorders, but scientists have observed a large number of skin cancer in populations, such as Bangladesh, with high arsenic water content.

"People have supposed (arsenic causes) lung, liver, bladder, kidney and colon (cancers), but they don't know for a fact," he said.

Acute arsenic poisoning, which is a large amount in a small time, causes neurological and gastrointestinal damage which can lead to death. According to the ATSDR, lower levels can cause nausea and vomiting, decreased production of red and white blood cells, damage to blood vessels and a sensation of "pins and needles" in hands and feet.

But a lot isn't known about the consequences of arsenic poisoning. For instance, scientists haven't recorded if arsenic exposure can result in birth defects or other developmental effects.

The ATSDR recommends families living in an area with high levels of arsenic to find a cleaner water source.

Contact Becky Bosshart at bbosshart@lahontanvalleynews.com