Chromium - The Risk Assessment Information System

Dose (mg Cr VI/kg bw/day)
1000.000
100.000
10.000
1.000
0.100
0.010
68
69
83
83
83
83
69
79
77
77
88
82
88
82
66
72
69
68 69
Figure 6.2 Mammalian TRV Derivation for Hexavalent Chromium
73
73
67
72
72
73
88
88
80
68
72
Data Evaluation Score
Lowest-Observed Adverse Effect Dose
Paired values from same study when joined by line
No-Observed Adverse Effect Dose
Wildlife TRV Derivation Process
1) There are at least three results available for two test species within the growth, reproduction, and mortality effect groups. There are enough data to derive a TRV.
2) There are three NOAEL results available for calculation of a geometric mean.
4) The geometric mean is equal to 9.24 mg/kg bw/d. The geometric mean is lower than the lowest bounded LOAEL for growth, reproduction or mortality.
5) The mammalian wildlife TRV for hexavalent chromium is equal to 9.24 mg chromium/kg bw/day which is equal to the geometric mean of NOAEL values
for reproduction and growth.
78
81
88 81
80 80
92
92
80 80
80
Geometric Mean of
NOAELs for REP and
GRO = 9.24
73 74 74
74 75 74
74
70
74
92
92
86
92
78
79 78 78
78
78
90 79 69 78
78 78
92
90
70
72
76
72
72
87 85
79
87 87 79
77 74
Biochemical (BIO) Behavior (BEH) Physiology (PHY) Pathology (PTH) Reproduction (REP)
Growth (GRO) Mortality (MOR)
BIO-NOAEL BIO-LOAEL BEH-NOAEL BEH-LOAEL PHY-NOAEL PHY-LOAEL PTH-NOAEL PTH-LOAEL REP-NOAEL REP-LOAEL GRO-NOAEL GRO-LOAEL MOR-NOAEL MOR-LOAEL
Eco-SSL for Chromium 15 April 2008
83
73 74
79
79
73