Bleached Kraft Pulp Mill Effluent Research Articles

Sublethal effects of simulated pulp mill effluents on the respiration and energy metabolism of rainbow trout ( Salmo gairdneri)

Rainbow trout were exposed to 0.08 × 96-hr LC 50 concentration of simulated unbleached (KME-Sa) and bleached (KME-Sa + CP) kraft pulp mill effluents. A sulfate soap preparation (Sa) with and without added chlorophenols (CP) was used as the toxicant mixture. The lipid content of white muscle increased in both test groups, and its protein content decreased in the KME-Sa-treated group. The ammonia excretion rate also decreased in both test groups. These results show that there was a shift from protein to lipid metabolism. On the other hand, apart from a slight hypoglycemia, only minor changes were observed in the carbohydrate metabolism. The overall effects on blood respiratory properties were functionally insignificant. However, the effects of kraft mill effluent with and without chlorophenols were qualitatively dissimilar in several respects.

Ecotoxicological aspects of pulp and paper mill effluents discharged to an inland water system: Distribution in water, and toxicant residues and physiological effects in caged fish (Salmo gairdneri)

Simultaneous studies were conducted on concentrations of chlorinated phenolics (CP) and resin acids (RA) in bleached kraft pulp mill effluents (BKME), their distribution in the receiving water, their uptake and accumulation in the blood plasma of rainbow trout caged in the recipient, as well as short-term physiological effects developed in fish. RA disappeared from the lake water much faster than most of the CP. Some of the BKME-related substances (e.g. 2,4,6-trichlorophenol, 4,5,6-trichloroguaiacol, tetrachloroguaiacol and dehydroabietic acid) were also detected upstream from the mill, thus implying a low-level contamination of this water system in general. In the blood plasma of caged trout free RA were detected up to 3 km from the sewer, but free CP were analysed as far as 11 km from the mill. During the 10-day caging period a partial inhibition of liver UDP-glucuronosyltransferase was observed even at 11 km from the BKME source. Brain acetylcholinesterase activity showed that BKME did not work like anticholinesterase agents, whereas a decrease of plasma cholinesterase activity was developed in a few days in the nearest 6 km from the sewer. Trout exposed at 6–11 km from the sewer displayed increased blood haemoglobin and decreased plasma protein concentrations. The plasma ionic picture (Na, Cl, Mg) indicated only negligible effects on fish osmoregulation.

Mortality, growth and fecundity of transplanted mussel and barnacle populations near a pulp mill outfall

The mortality, growth and fecundity of transplanted adult mussel (Mytilus edulis) and barnacle (Balanus glandula) populations near a kraft pulp mill outfall at Port Mellon, British Columbia, were determined. The results indicated that adults of both species were tolerant of bleached kraft pulp mill effluent and survived near the pulp mill outfall. However, the growth rates of both species were retarded when compared with those at the control station. The reproductive activities of the transplanted barnacles were also impaired.

Stress and Chronic Effects of Untreated and Treated Bleached Kraft Pulpmill Effluent on the Biochemistry and Stamina of Juvenile Coho Salmon (Oncorhynchus kisutch)

Growth of juvenile coho salmon (Oncorhynchus kisutch) fed a limiting ration (70% of satiation) in experimental stream channels was not altered significantly by prolonged exposure to untreated or laboratory-treated (fermented) bleached kraft pulpmill effluent (BKME), although mean weights for control fish were consistently lower than those for all effluent-exposed groups from 100 to 200 d. Body protein, fat, and moisture content were unaffected by treatment at 30, 90, and 200 d. Fish exposed to all strengths of untreated or treated BKME (i.e. untreated concentrations equivalent by volume to 0.05, 0.1, 0.2, 0.3, and 0.5 of the untreated effluent's 96-h LC50 value; and treated concentrations equivalent by volume to 0.2 and 1.0 LC50) showed significant decreases in serum albumin levels at 30 d, whereas these recovered to control values at 90 and 200 d. The serum electrolytes Na+, K+, and Ca++ were unaffected by treatment at 200 d and not measured for other exposures. Liver and muscle glycogen reserves were decreased significantly by continuous exposure of fish to untreated or treated BKME concentrations for 30 d. These values recovered to control levels at 90 d and were unaffected or depressed at 200 d. Plasma glucose levels at 30 d were elevated significantly in all BKME-exposed groups except those held in the lowest concentration of untreated or treated effluent. Blood sugar values at 90 d were increased only by the highest strength of untreated or treated BKME; whereas at 200 d these values were elevated from control levels in all effluent-exposed groups. Levels of plasma lactic acid were unmeasured at 30 d, increased at 90 d in all BKME-exposed groups except the lowest strength of untreated effluent, and elevated at 200 d in all effluent-exposed groups. The stamina of these fish as determined by critical swimming speeds in freshwater was unaffected by exposure to pulpmill effluent for 90 d and unmeasured for other exposures. Based on the changes in intermediary metabolism for BKME-exposed fish at 30, 90, and 200 d, it was concluded that these fish remained in a state of chronic stress and did not acclimate to prolonged exposure to pulpmill effluent. Treatment of this waste reduced or removed its acute (lethal) toxicity but did not alter the biochemical effects caused by chronic exposure. Key words: stress, growth, proximate analyses, albumin, electrolyte, glycogen, glucose, lactate, critical swimming speed, acclimation

Effect of Seasonal Photoperiod on Acute Toxic Responses of Juvenile Rainbow Trout (Salmo gairdneri) to Pulpmill Effluent

Acute toxic responses to bleached kraft pulpmill effluent were compared for groups of underyearling rainbow trout (Salmo gairdneri) reared under constant temperature and either a summer (16L:8D) or winter (8L:16D) photoperiod. Toxicity tests included a 96-h LC50 bioassay, a 4.5-h sealed-jar test, an 18-h temperature tolerance test, and a 4-h blood-sugar stress bioassay. For all tests the threshold-effect concentration of effluent was not affected by photoperiod. Median effective concentrations for the blood-sugar, temperature tolerance, and sealed-jar tests were, respectively, < 0.2, 0.4, and ~1.4 times the 96-h LC50 value for each fish group. Key words: Salmo gairdneri, photoperiod, BKME, acute toxicity tests, LC50, blood sugar, temperature tolerance, residual oxygen

Disruption of precopulatory behavior in the amphipod Anisogammarus pugettensis upon exposure to bleached kraft pulpmill effluent

Marine amphipods in precopula, Anisogammarus pugettensis (Dana), were used in static 117 h bioassays with neutralized, filtered, bleached kraft pulp mill effluent (BKME) and daily solution replacement. The effluent interfered with precopula behavior; high concentrations (40% of full strength BKME) resulted in rapid release of paired amphipods. A concentration-related time to 50% release of paired individuals was observed. For one batch of BKME, the behavioral threshold concentration (EC 50) was estimated at 10–15% of full strength BKME. The estimated 96 h LC 50 for underyearling coho salmon ( Oncorhynchus kisutch) for the same effluent tested in freshwater was 36% BKME—illustrating a greater sensitivity of the amphipod behavioral bioassay in comparison to the salmonid acute lethal toxicity test. The amphipod precopula bioassay for toxicity testing has some merit in that it is moderately quantitative under given test conditions and does not require elaborate equipment.

Leucocrit: A Simple Hematological Technique for Measuring Acute Stress in Salmonid Fish, Including Stressful Concentrations of Pulpmill Effluent

The number of leucocytes and thrombocytes in the circulating blood of fishes seems to reflect more accurately than the number of erythrocytes the fish's reaction to acute stress, including that caused by pollution. To facilitate the estimation of leucocytes in fish blood, a new test is being introduced called leucocrit, which is based on the determination of the volume of packed leucocytes–thrombocytes expressed as a percentage of the whole blood. For stocks of juvenile coho salmon (Oncorhynchus kisutch) and rainbow trout (Salmo gairdneri) held in freshwater under a variety of conditions, mean leucocrit values varied from 0.55 to 1.91%. Variations in age, species, food ration, degree of crowding, and prior disturbances offish stocks were associated with these differences. Leucocrit and leucocyte–thrombocyte counts for both species were depressed from stock values after 96-h or shorter (rainbow) exposure to stressful (high-temperature crowded) conditions; values for these measures were positively correlated but uncorrected with hematocrit values. Hematological values for subpopulations of underyearling rainbow trout reared under summer or winter photoperiod conditions were unaffected by photoperiod and responded similarly to acute stress. Leucocrit values for stocks of coho (1.30 ± 0.27%) and rainbow (0.92 ± 0.12%) were depressed due to transfer or acute exposure to bleached kraft pulpmill effluent (BKME). A 24-h exposure to BKME after 2 days' acclimation caused consistent leucocrit depressions, with median effective concentrations of 0.28 of the 96-h LC50 value for coho and 0.16 LC50 for rainbow. Hematocrit showed less sensitive or consistent changes due to stress or effluent exposure than leucocrit. Key words: leucocrit, leucocyte–thrombocyte count, hematocrit, blood, acute stress, BKME, pulpmill effluent, sublethal, salmonid fish, applications

Sealed-Jar Bioassays for Pulpmill Effluent Toxicity: Effects of Fish Species and Temperature

To standardize the sealed-jar bioassay for optimum sensitivity to whole bleached kraft pulpmill effluent, experiments were designed to assess the effects of test temperature, acclimation temperature, and fish species. Coho salmon (Oncorhynchus kisutch) conformed to a previously recognized test paradigm by showing progressively decreased oxygen utilization with increasing toxicant concentrations; however, rainbow trout (Salmo gairdneri) did not. In concentrations of effluent < 1.5 LC50, rainbow trout used significantly more oxygen than control groups, while coho salmon used significantly less oxygen. The sensitivity of these responses was influenced by test temperature and acclimation temperature. Results for coho confirmed that this species was most sensitive to effluent when tested at ambient room temperature. Both species showed significantly decreased oxygen utilization in effluent concentrations > 1.5 LC50 irrespective of test temperature or acclimation temperature. The significance of these responses is discussed, and the applicability of sealed-jar bioassays for assessing the acute toxicity of pulpmill effluents is reviewed. Key words: residual oxygen bioassay, sealed-jar bioassay, pulpmill effluent toxicity, temperature, hyperthermia, respiration, hypoxia, species-specific response

Avoidance of Bleached Kraft Pulpmill Effluent by Pinfish (Lagodon rhomboides) and Gulf Killifish (Fundulus grandis)

Avoidance of bleached kraft pulpmill effluent (BKME) by fish was investigated in a steep gradient trough. No significant difference was found between the responses of the two species. No avoidance was recorded at 0.01% BKME, while both species displayed a significant yet low avoidance at 0.1% BKME. A marked avoidance was observed for both species at 1.0% and 10.0% BKME. In both species the threshold avoidance level was estimated to be 0.06% BKME. Key words: avoidance responses, pulpmill effluent, estuarine fishes

Swimming Performance of Juvenile Coho Salmon (Oncorhynchus kisutch) Exposed to Bleached Kraft Pulpmill Effluent

Maximum critical swimming speeds were not achieved by fingerling coho salmon (Oncorhynchus kisutch) in concentrations of bleached kraft pulpmill effluent above a threshold concentration between 10–20% of the 96-h LC50. Reduction of swimming performance was related to effluent concentration but not to exposure time after the initial 18 h. Swimming performance returned to control levels for fish tested in water after 6–12 h recovery from exposure to effluent concentrations up to 0.7 LC50. Effluent was rendered nontoxic by aerobic microbiological fermentation but some reduction in swimming performance was measured which was attributed, in part, to the effects of color and lignin materials remaining after treatment.The results are discussed in relation to the mode of toxic action of bleached kraft pulpmill effluents and their possible impact on aquatic ecosystems.

Effects of Acute Exposure to Bleached Kraft Pulpmill Effluent on Carbohydrate Metabolism of Juvenile Coho Salmon (Oncorhynchus kisutch) During Rest and Exercise

In the static study (no exercise), liver glycogen stores were unchanged during 12-h exposure to 0.8 of the 96-h LC50; longer exposures caused a progressive decrease to levels one fifth those of controls at 72 h. Plasma glucose levels in fish held in 0.8 LC50 effluent for 3–96 h were elevated; at 96 h, glucose had increased threefold. Mean values for plasma lactate were elevated significantly at 3, 6, 24, 72, and 96 h.In the exercise (swimming one body length per second)–rest study, muscle glycogen levels decreased 53–78% during exercise in water or effluent (0.7 LC50) for 4–12 h, and did not recover during 12-h rest in water. Muscle glycogen for fish exercised for 12 h in effluent and then rested for 4 or 12 h in effluent was lower compared to values for fish exercised in effluent and then rested in water. There was no difference in liver glycogen levels offish exercised in effluent or water for 4–12 h. Values of liver glycogen for fish exercised in effluent for 12 h and then rested for 4, 8, or 12 h in effluent decreased 60–70% compared to fish exercised in water for 12 h and then rested in water and by 55–65% from fish exercised in effluent for 12 h and rested in water for 4–12 h. Plasma glucose levels were elevated one- to fourfold during exercise in water or effluent. Fish resting in water for 4, 8, or 12 h following exercise in water had relatively stable glucose levels; whereas for fish exercised and then rested in effluent the glucose levels increased twofold during resting. Plasma lactate levels were elevated five- to sixfold during exercise in water or effluent for 4–12 h, declining to values 1–2 times those of stock fish within 4-h rest. Plasma lactate levels for fish exercised in effluent and then rested in effluent or water were continually higher than those for fish exercised and rested in water.It was concluded that measurement of carbohydrate metabolites, particularly blood sugar levels, in unexercised fish could prove useful as a rapid method for measuring toxicity of pulpmill effluents and other pollutants.

Bioassay Procedures to Evaluate Acute Toxicity of Neutralized Bleached Kraft Pulp Mill Effluent to Pacific Salmon

A series of bioassays was carried out to assess the acute toxicity of neutralized, filtered, bleached kraft pulp mill effluent (BKME) from a single mill to underyearling Pacific salmon in fresh soft water, at 10–13 C. Toxicity expressed in terms of the 96-hr LC50 varied from 22% of full strength BKME to nontoxic in different collections. A procedure is described for estimating the 4-day LC50 from geometric mean survival time data. Toxicity of effluents changed unpredictably with storage (even at 2 C), and declined with air stripping. Comparison of continuous flow and static test procedures indicated that continuous flow procedures yield somewhat higher toxicity results than static tests. Experiments with varying fish densities indicate that measurable toxicity is less in static tests with heavy fish loading. Use of loading densities of 2.5 liters/g fish or better is recommended. Young sockeye salmon (Oncorhynchus nerka) appeared most sensitive, and pink (O. gorbuscha) and coho (O. kisutch) salmon somewhat more resistant to toxic BKME solutions. No correlation was found between time to death and condition factor in the size range of underyearling coho tested (3.0–7.3 cm). Recommendations are made for routine and regulatory bioassay procedures.

Application of Polyacrylamide to Pulp Mill Effluents

This paper was to study how to apply polyacrylamide (PAA) as a pollution control reagent to bleached Kraft pulp mill effluents. The following problems were discussed : 1) the suitable aluminum sulfate (Alum) dosage, 2) effects of the molecular weight of PAA, 3) effects of the PAA dosage, 4) effects of pH on coagulation.The results are as follows. Removal of COD does not depend on the dosage of PAA, but that of alum. The role of PAA is to make a large and strong coagulation and to result fast sedimentation of it. To form good coagulations, 5 million or more of mol. wt, of PAA is required. The more the dosage of PAA, the faster the rate of sedimentation. Nonionic PAA gives the maximum rate of sedimentation at pH 5-7. Anionic PAA, independently of its degree of hydrolysis (DH), shows the maximum rate of sedimentation at pH 8.

Toxicity of kraft pulp mill effluent for larval and adult lobsters, and juvenile salmon

The lethal threshold concentration of neutralized bleached kraft pulp mill effluent for juvenile Atlantic salmon ( Salmo salar L.) is about 12–15% in fresh water. This agrees in general with work on other salmonid fish. Larval lobsters ( Homarus americanus Milne-Edwards) are reasonably resistant to this waste, and concentrations below 10% did not greatly affect their survival in sea water. Adult lobsters in sea water are more resistant than lobster larvae or salmon parr.