Seers have long forecast the day when fertilizers would be regulated much like pesticides in California.
That day is at hand with the new California Food and Agriculture Code regulations, effective Jan. 1, 2002, for content of arsenic, cadmium, and lead in commercial, inorganic fertilizers, and the fertilizer industry has prepared for them.
At the recent conference of the Fertilizer Research and Education Program (FREP) in Tulare, John Donahue, retiring director of the California Department of Food and Agriculture Division of Inspection Services, discussed the new regulations.
CDFA's FREP, which channeled the scientific studies for the regulations, is charged with improving the efficiency of commercial fertilizer use and minimizing loss of nitrogen to the environment.
Its projects are funded by nearly $1 million per year by the mill tax on sale of commercial fertilizers in the state. It has bankrolled 92 research and education projects since 1990.
Donahue said the new heavy metal regulations sprang from a directive given him in 1998 by then-CDFA Secretary Ann Veneman when he transferred to the division from the California Department of Pesticide Regulation.
FREP handled the risk assessment for heavy metals portion through a “facilitated rulemaking process,” and after a series of public hearings, allowing for input from environmental interests and the manufactured fertilizer industry, revisions the regulations were hammered out.
In part, the new regs specify for each percent of iron, manganese, or zinc the following concentrations: arsenic, 13 parts per million; cadmium, 12 ppm; and lead, 140 ppm.
For each percent of phosphate, the limit for arsenic, for example, diminishes from 4 ppm in 2002, the first year, to 3 ppm the second, and 2 ppm the third. The limit for cadmium is also phased in with a similar, declining pattern during three years.
The regulations also address sampling and testing of recycled material used in zinc, manganese, or iron products utilized as a base (containing phosphate, zinc, manganese, or iron) fertilizing ingredient. They also lay down provisions for labeling requirements, including a guarantee statement, or packaging labels, or information telephone number or Web site address.
In announcing the new regulations, a CDFA press release stated that manufactured fertilizers in the 1990s revealed potentially high levels of heavy metals. However, it said, “by 1999 and 2000, follow-up studies found almost 100 percent compliance with the new 2002 standards as fertilizer manufacturers made adaptations in anticipation of these regulations.”
CDFA Secretary William “Bill” Lyons Jr. said the standards “ensure that levels of certain heavy metals will not pose a risk to people or the environment in California.”
Another presenter at the FREP conference, Andrew C. Chang, professor of environmental sciences at the University of California, Riverside, said technology now exists to reduce the amount of trace elements, or heavy metals, in fertilizers.
His research has focused on land application of reclaimed municipal wastewater and evaluation of heavy metals in soils treated with biosolids. He and his colleagues at UCR did a study on trace elements in California cropland.
Although trace elements, such as arsenic, cadmium, and lead, occur naturally in the environment, he said the concerns with them are their relatively narrow biosafety margins. They are essential to life forms, but when the amount becomes slightly higher, in combination with elevated levels of phosphorous, they become toxic.
He said that even though arsenic, for example, remains in some California soils after use of arsenic-based herbicides and insecticides in the 1930s and 1940s, it is not being transferred into plant tissue.
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