94
S.L. Chang
Table 1. Small Free-Living Amoebae in Aerobic Sewage Effluents,
Fresh Surface Waters, and Outdoor Swimming Pools
Samples examined
Waste effluents
Cincinnati trickling filters
Lebanon stabilization ponds
Surface waters
Kentucky lake 1
No. of Amoebae
gal"
1
50,000 ± 6,000
35,000 ±4,000
150 ±40
Amoebae isolated in cultures
and % in total amoebae
A. rhysodes
N. gruben
Others
A. rhysodes
N. gruben
Others
N. gruben
(65%)
(18%)
(17%)
(60%)
(20%)
(20%)
(42%)
lake 2
Florida lake 1 *
lake 2
lake 3
lake 4
lake 5
lake 6
Ohio River near Cincinnati
Missouri River near Kansas
Swimmingpools
Cincinnati pool 1
pool 2
pool 3
150 ±40
350 ± 65
130
190
185
200
110
140
800 ±167
320 ± 60
18 ± 7
21 ±8
11 ±5
N. gruben
A.rhysodes
Others
A. rhysodes
N. gruben
Others
TV. grub eri
N. gruben
N. gruben
N. gruberi, A.
N. gruberi, H.
(42%)
(30%)
(28%)
(45%)
(40%)
(15%)
radiosa
agricola
Schizopyrenus russelli
A. rhysodes
N. gruberi
Others
A. rhysodes
N. gruberi
Others
A. rhysodes
N. gruberi
A. thysodes
N. gruberi
H. agricola
A.rhysodes
N. gruberi
(80%)
(18%)
(2%)
(60%)
(15%)
(25%)
(83%)
(17%)
(86%)
(10%)
(4%)
(90%)
(10%)
*These results were obtained from a cooperative study with the Division of Health, Florida State
Department of Health and Rehabilitation Service. More samples will be examined and results will be
reported in detail when the study is completed.