Recovery facilitation of malathion-intoxicated freshwater fish by exposure to hypertonic environment.
The possibility of recovery in a hypertonic environment (10-40% NaCl) was investigated in the freshwater fish Oreochromis niloticus acutely intoxicated with the pesticide Malathion (40 mg/l). Survival was significantly higher in 15 g/l NaCl, with a shorter time required to recover posture and swimming, although 20% of recovered animals died on subsequent days. Exposure to a hypertonic environment plus pesticide did not protect the animals. Fish exposed to air until they became unresponsive recovered faster in freshwater than in a hypertonic environment. It is concluded that a hypertonic environment only facilitates recovery and that although osmotic mechanisms may explain the results, other possibilities remain to be investigated.
Lopes
L R
LR
Departamento de Fisiologia, Universidade Estadual Paulista, Botucatu, Brasil.
Santos
S
S
Dell'Aqua
J P
JP
Del-Carratore
C R
CR
Hoshino
K
K
D000818:Animals; D004781:Environmental Exposure; D005260:Female; D005399:Fishes / Q000502:physiology*; D006982:Hypertonic Solutions / Q000494:pharmacology*; D008294:Malathion / Q000633:toxicity*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009997:Osmotic Pressure
D006982:Hypertonic Solutions; D008294:Malathion