Daily News Archive
From June 1, 2001

Elevated Levels of Chromium (VI) Found in Santa Cruz Area Wells

Hexavalent chromium, one of two highly toxic metals in the wood preservatives copper chromium arsenate (CCA), has been detected in six wells in Santa Cruz County, California. Chromium (VI) is the notorious chemical that caused cancer in the residents of Hinkley, CA and brought to light by the work of Erin Brockovich. Chromium (VI) along with arsenic are two of the key ingredients of CCA, to treat wood that is then used to build playgrounds, decks, boardwalks and utility poles. Both chromium (VI) and arsenic are categorized by the Environmental Protection Agency (EPA) as Class A, known human carcinogens.

Up to 38 ppb of chromium (VI) were found in the La Selva Beach area and one Scotts Valley well. Lower levels, from 6 to 18 ppb, were found in the Bonita Road, Rio Del Mar, and Aptos areas. Results for Watsonville, in the same aquifer as La Selva Beach, are expected soon, and may be as high or higher. Santa Cruz water officials have stepped up testing schedules and are awaiting results. Tests announced earlier this year have revealed chromium (VI) levels as high as 54 ppb in Los Angeles, 22 ppb in Riverside and San Bernardino, 18 ppb in Santa Barbara, 23 ppb in Yolo County, 10 ppb in Solano, and 4.1 ppb in Santa Clara.

Studies have established that both chromium (VI) and arsenic can cause a variety of health problems including respiratory and gastrointestinal illnesses, reproductive and birth defects, as well as cancer (see ATSDR's ToxFAQs on chromium and arsenic). Ingestion or skin contact at high enough levels can result in death. CCA treated wood has been the center of attention since elevated levels of arsenic were discovered in playgrounds in the soil underneath and on the surface of CCA treated wood playscapes in Florida. This led Florida officials to close a number of parks to protect the health of children. Both the St. Petersburg Times and the Gainesville Sun have covered the story extensively (click on the newspaper names to visit the articles on their websites).

For more information about the risks associated with CCA treated wood and the wood preservatives generally, contact Beyond Pesticides. Two reports on the risks linked to wood preservatives, Poison Poles and Pole Pollution, can be found on the Beyond Pesticides website.