STREAM POLLUTION 
421 
Cadmium sulphate, CdSO< 
Same sources as cadmium chloride. Carpenter (1927), 1,042 p. p. m. in distilled water killed 
minnows, Leuciscus phoxinus, in 3 hours. 
Calcium chloride, CaCL 
Wastes from bromine and salt works; in waters from oil wells; antidust road surfacing. Wells 
(1915b) 555 p. p. m. in tap water caused pathological degeneration of tail fin of rock-bass, Amblo- 
plites rupestris, in an exposure of 1 week; Garrey (1916), 2,775 p. p. m. in distilled water killed straw- 
colored minnows, Notropis blennius, in 2-4 days, but this species did not succumb to 277 p. p. m. 
in distilled water in 5-7 weeks; Powers (1917), 7,752 p. p. m. in distilled water killed goldfish, 
Carassius auratus, in 22-27 hours; Wiebe, Burr, and Faubion (1934), 5,000 p. p. m. killed golden 
shiners, Notemigonus crysoleucas, in 143 hours. 
Calcium hydroxide, Ca(OH) 2 - Lime 
Tannery-wastes; leather works. Weigelt, Saare, and Schwab (1885), 700 p. p. m. in tap water 
killed trout in 26 minutes; Marsh (1907), 18 p. p. m. (as calcium oxide) fatal to trout fry. 
Calcium nitrate, Ca(N0 3 )2 
Some chemical wastes. Powers (1917), 6,061 p. p. m. in distilled water killed goldfish, in 43-48 
hours. 
Calcium oxide, CaO. Unslaked lime 
Forms calcium hydroxide, q. v., immediately on addition to water. 
Carbon bisulphide, CS 2 
Gas wastes; as a solvent in various chemical industries. Weigelt, Saare and Schwab (1885), a 
7 minute exposure to 5,000 p. p. m. killed trout 2 days later; Shelford (1917), 100-127 p. p. m. in 
tap water killed orange-spotted sunfish, Lepomis humilis, in 1 hour. 
Carbon dioxide, CO 2 
From sewage and any decomposing organic wastes (see section on carbon dioxide in natural 
waters). Wells (1918), 113,925-151,900 p. p. m. in tap water killed fresh-water fishes. 
Carbon monoxide, CO 
Motorboat exhausts; in water returned to streams from cooling systems of engines using fuel oil 
if mixed with exhaust gases. Wells (1918), 1,160 p. p. m. in tap water killed straw-colored minnow, 
Notropis blennius, in 1 hour; the blunt-nosed minnow, Pimephales notatus, in 1 hour 55 minutes; 
the orange-spotted sunfish, Lepomis humilis, in 5 hours 40 minutes; the green sunfish, Lepomis 
cyanellus, in 6 hours; 11,314 p. p. m. under same conditions killed the black bullhead, Ameiurus 
melas, in 9 hours 55 minutes. 
Chloramine, NH 2 CI 
W'ater purification systems either as chloramine or formed from small quantities of ammonia 
and chlorine in the water. Coventry, Shelford, and Miller (1935), 0.3-0. 4 p. p. m. in tap water 
killed trout fry at once, and 0.06 p. p. m., trout fry in 48 hours; 0.4 p. p. m. killed sunfish and bull- 
heads; 0.76 p. p. m., hardy minnows; and 1.2 p. p. m., large carp and bullheads. 
Chloramine-T, CH 3 C6H4S02NNaCl 
Water purification systems. Adams (1927), 5 p. p. m. in Nile River water killed cladocerans, 
Daphnia sp., and copepods, Cyclops sp. 
Chlorine, CI 2 
Water purification systems; various chemical wastes. Adams (1927), 2 p. p. m. in Nile River 
water killed cladocerans, Daphnia sp., and copepods, Cyclops sp.; Davis (1934), 1 p. p. m. killed 
coarse fish; M. M. E., 1 p. p. m. in hard water killed goldfish, Carassius auratus, in 96 hours; and 
0.5 p. p. m. in soft water killed cladocerans, Daphnia magna, in 72 hours or mpre. 
