Table 1–1:

Water Effect Ratios from early studies:

Metal	Water bodies	Number of Studies	Water Effect Ratios (range)
Copper	4 Eastern & Midwestern Rivers1	8	1.1 – 15.3
Zinc	4 Eastern & Midwestern Rivers1	9	1.2 – 2.9
Cadmium	4 Eastern & Midwestern Rivers1	20	1.0 – 10.8
Chromium	2 Midwestern Rivers1	2	1.2 – 2.7
Lead	1 Midwestern River1	4	1.9 – 5.7
Nickel	1 Gulf estuary1	1	1.6
Copper	3 Eastern Rivers2	3	26 – 64
Zinc	1 Eastern River2	1	2.4
Cadmium	1 Eastern River2	1	38

¹ Brungs et al., 1992

²additional studies reported by Hall and Raider, 1993.