416 
BULLETIN OF BUREAU OF FISHERIES 
have been responsible for these cumulative effects), these experiments do show that 
precipitated and insoluble substances on the bottom of the stream can be a definite 
pollution hazard over a long period of time due to cumulative action. Again, the 
writer has found that insoluble zinc ore (zinc sulphide) carried by a stream and de- 
posited on flats adjacent to the main stream bed during high water when exposed to 
the actions of sunlight, air, and moisture produced quantities of zinc sulphate, a 
freely soluble and definitely toxic compound which was leached back through into 
the stream subsequently by rains and high waters (Ellis, 1932). 
The synergistic physiological action of many compounds is well known, and the 
work of Macht and Leach (1930) on goldfish and other types of animals may be 
cited in this connection, as these writers found that two or more octylic alcohols were 
synergistic in their action on the respiratory and neuromuscular mechanisms of 
animals. 
MISCELLANEOUS COMPOUNDS 
In tables 12 and 13 the relative toxicities of 13 other substances found in indus- 
trial wastes or otherwise constituting stream pollution hazards are presented. The 
changes in hydrogen -ion concentra tion and salt balance are shown, as in the tables 
giving the data on acids and metallic compounds. It may be seen, however, that 
the substances listed in tables 12 and 13 do not kill because of changes either in pH or 
salt balance, i. e., in these two tables are included representatives of those substances 
which, if detrimental, are so because of specific toxic action after entering the body 
of the fish. Phenol produces paralysis of the neuromuscular mechanisms and 
hemolyzes the blood; potassium xanthate in high dilution acts after several days on 
the gastrointestinal tract; amyl alcohol quickly induces a semiparalyzed condition 
with marked incoordination, yet the fish may live for days in this state before dying; 
and sodium selenite causes a slow decline in the general activities of the fish. 
Table 12. — Survival of goldfish in solutions of sulphur and selenium compounds 1 
Substance 
Concentra- 
tion ratio 
by weight 
Parts 
per 
mil- 
lion 
Diluent 
water 
pH 
Specific con- 
ductivity 
mho X 10-» 
at 25° C. 
Survival time 2 
Constituent of— 
Water 
Solu- 
tion 
Water 
Solu- 
tion 
Ammonium sulphide.- 
3 1:1,000 
1, 000 
Hard - 
7.7 
7.9 
681 
938 
15 minutes to 1 hour 
Do. 
3 1:10,000 
100 
do 
7.7 
7.8 
681 
735 
30 minutes. 
72 hours to oo. 
Sewage and or- 
Do 
3 1:100,000 
10 
do 
7.7 
7.7 
681 
681 
ganic wastes. 
Do_ 
3 1:1,000,000 
1 
do 
7.7 
7.7 
681 
681 
OO 
Hydrogen sulphide 
3 1:1,000 
1, 000 
_-do 
7.8 
6.5 
670 
734 
45 minutes to 1 hour 
Do. 
3 1:10,000 
100 
7.8 
7.3 
670 
676 
3 to 4 hours _ 
Do. 
Do 
3 1 : 100, 000 
10 
7.8 
7.6 
670 
661 
96 hours to oo _ 
Do 
3 1:1,000' 000 
1 
7.8 
7.7 
670 
670 
Sodium sulphite 
3 1:1,000 
1,000 
do 
7.8 
7.6 
676 
2,017 
3 to 72 hours. 
Do 
3 1:10,000 
100 
do _-- __ 
7.8 
7.6 
676 
864 
96 hours to oo _ _ 
Paper-pulp-mill 
Do 
3 1:100, 000 
10 
do 
7.8 
7.6 
676 
678 
wastes. 
Do 
3 1:1,000, 000 
1 
- .do _- 
7.8 
7.8 
676 
677 
m 
Sodium selenite 
1 : 1, 000 
1,000 
Very soft 
6.4 
7.5 
<50 
753 
1 hour to 1 hour 30 min- 
utes 
Do 
1:1, 000 
1,000 
Hard--- 
7.8 
7.4 
647 
1, 141 
1 hour to 2 hours 10 min- 
utes. 
Do 
1:10, 000 
100 
Very soft 
6.4 
7.6 
<50 
107 
20 hours 56 minutes to 
Certain soils. 
Do 
1:10,000 
100 
Hard 
7.8 
7.7 
647 
723 
8 hours to 19 hours 30 
minutes. 
Do 
1:100, 000 
10 
Very soft 
6.4 
7.3 
<50 
<50 
98 to 144 hours 
1 Conditions of experiments described in table 8. 
3 Minimal and maximal survival times as found in these experiments. Infinity sign indicates survival greater than 4 days 
without any apparent injury to the fish. 
1 Constant flow as described in table 8- 
