Zinc - The Risk Assessment Information System

3.0 ECO-SSL FOR TERRESTRIAL PLANTS
Of the papers identified from the literature search process, 680 papers were selected for
acquisition for further review. Of those papers acquired, 78 met all 11 Study Acceptance Criteria
(U.S. EPA, 2003; Attachment 3-1). Each of these papers were reviewed and the studies were
scored according to the Eco-SSL guidance (U.S. EPA, 2003; Attachment 3-2). Thirty-nine study
results received an Evaluation Score greater than ten (U.S. EPA, 2003; Attachment 3-1). These
studies are listed in Table 3.1.
The studies in Table 3.1 are sorted by bioavailability score. There are five studies with a
bioavailability score of 2 that are eligible for Eco-SSL derivation. These results were used to
derive the plant Eco-SSL for zinc (U.S. EPA, 2003; Attachment 3-2). The Eco-SSL is the
geometric mean of the maximum acceptable toxicant concentration (MATC) values for three
species under different test conditions (pH and % organic matter (OM)) and is equal to 160 mg/kg
dw.
4.0 ECO-SSL FOR SOIL INVERTEBRATES
Of the papers identified from the literature search process, 162 papers were selected for
acquisition for further review. Of those papers acquired, 26 met all 11 Study Acceptance Criteria
(U.S. EPA 2003; Attachment 3-1). Each of these papers were reviewed and the studies were
scored according to the Eco-SSL guidance (U.S. EPA, 2003; Attachment 3-2). Forty studies
received an Evaluation Score greater than ten. These studies are listed in Table 4.1.
The studies in Table 4.1 are sorted by bioavailability score. There are six studies with a
bioavailability score of 2 that are eligible for Eco-SSL derivation. These results were used to
derive the soil invertebrate Eco-SSL for zinc (U.S. EPA, 2003; Attachment 3-2). The Eco-SSL is
the geometric mean of the EC 10 and MATC values for at least three test species under different
test conditions (pH and OM%) and is equal to 120 mg/kg dw.
Eco-SSL for Zinc 4
June 2007