EFFECTS OF SUBLETHAL CONCENTRATIONS OF SEVERAL TOXICANTS ON GROWTH OF THE COMMON GUPPY, <i>LEBISTES RETICULATUS</i>1

Abstract

The effect of prolonged exposure to sublethal concentrations of lead, zinc, and sodium pentachlorophenate were studied in the common guppy, Lebistes reticulatus. The concentrations used were 2 ppm lead nitrate (1.25 ppm as lead), five ppm hydrated zinc sulfate (1.15 ppm as zinc), and 0.5 ppm sodium pentachlorophenate. In addition, several fish were placed in 5 ppm lead nitrate (2.48 ppm as lead) and 10 ppm hydrated zinc sulfate (2.30 ppm as zinc). Newborn fish were added to the experimental and control solutions. At 30 days of age, the fish were weighed individually on an analytical balance. After this initial weighing, the fish were weighed at 15‐day intervals until the 90th day. Daily observations were made for the presence of sexually mature fish and any dead fish. It was found that with all three toxicants growth was retarded, mortality was increased, and sexual maturity was delayed.