Impact of pulp and paper mill effluent on egg hatchability of pike (Esox lucius L.)
Toxicants affect reproduction often at concentrations well below lethal levels. Also, the acidification of fresh waters has been shown to cause extinction of teleost fish populations usually through a failure of recruitment from younger generations. Both field and laboratory studies have documented that the greatest susceptibility to low pH occurs in the early developmental stages (e.g. Lee et al. 1983; Peterson 1984). Also low concetrations of metals (Horning & Neisel 1979; Ozoh 1979, 1980) and environmental accumulation of xenobiotics (Ozoh 1979; yon Westerhagen et al. 1981) diminish egg hatchability. In numerous toxicological studies egg hatchability has been a more sensitive indicator of toxic action than the other parameters studied (e.g. Henderson et al. 1981; DeGraeve et al. 1982; Lewis & Wee 1983). However, only relatively recently have the effects of bleached kraft pulp mill effluent (BKME) on fish reproduction (zebrafish Branchydanio rerio) been studied (Viktor et al. 1980; Viktor 1982) and no recipient species have been used.
Effects of pulp and paper mill effluent (BKME) on physiology and biochemistry of the roach (Rutilus rutilus L.)
The effects of bleached kraft pulp and paper mill effluent (BKME) on the roach (Rutilus rutilus L.) were studied under experimental and natural field conditions. In the acute experiment (72 h exposure to the concentrated BKME), the roach suffered from a general stress syndrome, characterized by a significant increase of cortisol and blood glucose, as well as a significant decrease of leucocrit and total plasma protein. In three weeks' exposure in a polluted and an unpolluted lake and in fish caught from the same lakes, the more specific effects of BKME treatments appeared. During the three weeks' exposure, slight hyperglycaemia as well as a decrease in a transaminase activity (GPT) and increase in the plasma total protein concentration of the fish occurred in the polluted lake. Fish caught from the polluted lake exhibited lower values of haematocrit, transaminases (GOT and GPT), and calcium concentration plus a higher chloride concentration in the plasma than in the unpolluted lake. The differential leukocyte counts also showed slight differences: Fewer lymphocytes and more granulocytes were found in roach from polluted waters. The morphology of the red blood cells in the roach from polluted lakes had more elongate erythrocytes with a longer major axis and a shorter minor axis than in fish from the polluted lake. The possibilities of determining the origin of fish based on their erythrocyte morphology is discussed.
Lead detoxification by a copper-tolerant isopod
THE acquisition of metal tolerance by freshwater and marine invertebrates in environments polluted by mine waste in southwest England has now been established1,2. Generally, for invertebrates such tolerance has been shown to be specific for particular metals1, although the literature suggests that co-tolerance may operate for copper and silver in the polychaete Nereis diversicolor3 and for zinc and nickel in the grass Agrostis tenuis4,5. We show here that co-tolerance operates in the isopod crustacean Asellus meridianus, in which tolerance to copper seems to confer tolerance to lead. Two populations of A. meridianus from differing habitats are also shown to use different methods for achieving lead tolerance.