Washington State Department of Ecology

Department of Ecology News Release

FOR IMMEDIATE RELEASE - Nov. 30, 1998

98-202

Contacts: Greg Sorlie, Hazardous Waste Program Manager, (360) 407-6702

Ron Langley, Public Information, (425) 649-7009

Studies find metals, dioxins in some fertilizers and soils

OLYMPIA - Preliminary studies released today by the Washington State Department of Ecology (Ecology) show that heavy metals and dioxins are present in some fertilizers. At the same time, another new study of heavy metals in agricultural soils concludes that metals do not appear to pose a threat to human health or the environment in the region studied.

"We have yet to see evidence that human health is threatened by the fertilizers used on farmland in Washington," said Jim O. White of the state Department of Health. "However, it is very important that we continue to monitor metals and dioxins to ensure that such a threat does not appear in the future."

Earlier this year, Washington passed the first law in the nation that set standards for heavy metals allowed in fertilizers sold to farmers and home consumers. During the past year, Ecology studied metals and dioxins in 51 fertilizers to enable the state to evaluate the adequacy of the new law, which is being used by the state Department of Agriculture to review all fertilizers sold in the state. Ecology also took soil samples to provide a limited but useful picture of metals and dioxins already present in state soils.

"Our goal is to find the relatively small number of fertilizers that add unacceptable amounts of metals to Washington’s soils," said Greg Sorlie, Ecology’s chief hazardous waste manager. "At the same time, we’re trying to learn more about the sources of dioxins in our state’s environment."

Results of the studies include the following:

Levels of zinc and cadmium were higher in soil samples from land that has been farmed for many years compared to land in the same area that has never been farmed. However, all soil samples had metals levels at the low end of a range of background levels established in earlier studies. All samples of agricultural soils were taken in the Columbia Basin Irrigation Project;
Dioxins are found in non-agricultural soils throughout the state at levels similar to those found in studies of other parts of the world. As expected, the highest levels were found in urban areas. A study of dioxin levels in agricultural soils may be conducted in 1999.
Most fertilizers have non-detectable or very low levels of dioxins, but three have dioxin levels high enough to merit further research into the source of dioxins found in those products;
The state subjected all of the fertilizer samples to a heavy metals test that must be passed by waste-derived fertilizers and found that seven products failed this test for cadmium. Ecology is researching the products that failed in order to determine whether they include industrial waste. Any of the fertilizers that contain recycled industrial waste could be found in violation of hazardous waste regulations and removed from the market in Washington unless the manufacturer is able to reformulate the product.

Several recommendations may come from the studies, but two are of particular interest to Ecology:

Metals levels in state soils should be periodically monitored to ensure that levels do not become a concern in the future;
Ecology will propose elimination of a federal exemption from hazardous waste regulations for steel mill flue dust. The exemption allows steel mill flue dust to bypass hazardous waste requirements when it is recycled into fertilizer. This proposed change, which must be subjected to a formal public process, would apply to Washington State only.

Final results and recommendations for action based on the new studies are expected in spring 1999 after Ecology discusses the information with experts in the field and with the state’s Fertilizer Advisory Workgroup. The group is made up of representatives from agriculture, environmental and labor groups, the fertilizer industry, and government agencies.