Levels of the chemical vanadium found in some of Oahu’s drinking water wells were higher than in federal guidelines but do not pose a health concern, according to both the Honolulu Board of Water Supply and the state Department of Health.
In 2013 for the first time, the Environmental Protection Agency asked the board and other water agencies nationwide to test for vanadium and 27 other unregulated contaminants, said Erwin Kawata, BWS Water Quality Division program administrator. That’s in addition to the more than 80 regulated contaminants that EPA requires all water agencies to include.
Information about what’s in the water Oahu consumers drink are contained in Water Quality Reports, BWS officials said.
Of the 28 identified unregulated contaminants tested in 2013, seven were detected in Oahu’s water system, Kawata said. Of the seven, only vanadium tested at levels higher than established EPA health guidelines.
BWS wells, primarily in Central Oahu, found vanadium levels as high as 52 parts per billion. The EPA advisory level is about 21 ppb.
BWS spokeswoman Jill Kuramoto said 21 ppb or higher was recorded at 19 of 85 well stations. Most were in Central Oahu, but some were also found in areas of West Oahu, including Makaha, Kunia and Waipahu, as well as in the North Shore and some areas of Windward Oahu, including Waimanalo, she said. The high level of 52 ppb was found in Waipahu, she said.
Gary Gill, the Health Department’s deputy director, said in a statement that vanadium occurs naturally in the earth’s crust and in groundwater. It can be found in areas where volcanic eruptions occur and where there is a prevalence of basalt rock.
Vanadium is released into water and soil as a result of weathering of rock and soil erosion, the Health Department said in a separate release.
Additionally, people are exposed to it naturally in food and water, and "it is not considered harmful," Gill said.
"Higher levels are often found in seafood and some nutritional food supplements, as well as coral, crude oil and, in lower amounts, in some types of fertilizers," the Health Department said. However, the agency pointed out that the Agency for Toxic Substances and Disease Registry states "exposures to the levels of vanadium naturally present in food and water are not considered to be harmful."
Studies in humans exposed to large amounts of vanadium showed reports of minor complaints such as stomach cramps, DOH said.
As a medicinal supplement, the mineral is used to treat diabetes, low blood sugar, high cholesterol, heart disease and tuberculosis, according to WebMD.com.
The EPA calls on water agencies to test for a series of unregulated contaminants every five years to help it determine the concentrations and prevalence of the chemicals, with the ultimate goal of determining whether there should be more frequent testing.
BWS is required to mail to customers its annual Water Quality Report for the previous year’s 12 months by July 1. Customers should already be getting them, Kuramoto said Monday.
Customer reports should show what contaminants are in the wells from which their water originates, BWS officials said.
Kawata said among the contaminants that already are regulated, the numbers were consistent with previous years.
Among the 28 elements and compounds EPA asked to be included in testing are several already regulated in Hawaii, including trichloropropane, also known as TCP, which was used as a soil fumigant through the 1960s.
Wells in Central Oahu from Waipahu to Haleiwa — where groundwater was contaminated by pesticides associated with pineapple cultivation — continue to be treated and filtrated to ensure levels are well below EPA’s allowable amounts, Kawata said.
He said he expects water in those areas will continue to be treated "for a number of years."
BWS received nearly $20 million in a settlement in 2002 with six petrochemical companies and pineapple growers over contamination of the water supply in Central and Leeward Oahu.
To learn more about BWS water quality reports, go to bit.ly/1iAx1iF.
