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In recent years, increasing efforts have focused on production of organic-inorganic compound fertilizers using ammonium sulfite pulping waste liquor. However, their ecological effects on soil have not been studied. In this study, earthworm Eisenia fetida was exposed to various doses (0, 0.13, 0.26 and 0.52 kg/m2) for different time (7, 14, 21, and 28 d) to evaluate the effects of fertilizers made from pulping waste liquor, including reactive oxygen species (ROS) generation, antioxidant enzymes activities, glutathione S-transferase enzyme (GST) activity, malondialdehyde (MDA) content and DNA damage. Results showed that there were significant increase of ROS and MDA levels after 14 d, inducing production of antioxidant enzymes (superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT)) as well as GST. Before 14 d, excess ROS and MDA caused damage to the DNA of earthworms, leading to gradual increase of Olive tail moment (OTM) in the comet assay. With the exposure time extended to 28 d, owing to the combined effects of elimination of free radicals by antioxidant enzymes and detoxification enzymes as well as self-repairing function of cells, ROS and MDA levels declined slightly and OTM gradually decreased. In summary, this study indicated that there was a toxicological effect on earthworms when fertilizers made from pulping waste liquor were applied to soil, which needs more attention.

The anchoveta (Engraulis ringens) and sardine (Strangomera bentincki) are coastal pelagic species with important spawning areas off the coast of Chile. The discharge of secondary-treated effluents from a kraft pulp plant near one of these spawning areas has raised environmental concerns. Therefore, effluent effects on the development of anchoveta and sardine eggs were assessed by in vitro exposure. Eggs were sampled between 2007 and 2010 off Talcahuano, Chile. Subsequent toxicity tests (96 h duration, 12 °C) were performed using increasing effluent concentrations, a filtered seawater control, and two potassium dichromate concentrations (to verify consistent embryonic sensitivity). Egg mortality and hatching success were evaluated. For anchoveta, mortality (9.9 ± 7.1%) did not significantly differ among groups in five toxicity tests except the final toxicity test that showed significant differences in mortality (5.6% control vs 27.8% in 100% effluent). For sardines, no differences in mortality existed between the effluent dilutions (2.6 ± 3.6%) and control (6.3 ± 3.9%). Notably, anchoveta egg survival and hatching success rates were inconsistent, i.e., the highest rates of hatching failure occurred on the same sampling date with the highest rates of survival for the 100% effluent group (72%). In conclusion, the obtained results indicate that (i) anchoveta egg mortality and hatching failure increase only under 100% effluent exposure, coinciding with decreased egg quality near the end of spawning season and (ii) high effluent dilutions not significantly increase sardine and anchoveta egg mortalities. Nevertheless, the recorded adverse effects to the hatching process should be studied in greater detail, particularly considering interspecific variability and the complexity of reproductive processes, especially during early development.

2,4,7,9-tetramethyl-5-decyne-4,7-diol (TMDD) is a high-production volume chemical used in paper, ink, pesticide, and adhesive industries as a wetting and anti-foaming agent. The physicochemical properties and slow biodegradation rate of TMDD indicate a low bioaccumulation potential but a high prevalence in the environment. As a consequence, TMDD has been detected in several European rivers in the nanogram per liter and lower microgram per liter range; however, its environmental risk to aquatic organisms is considered low. Recent studies almost exclusively focused on acute effects by TMDD, little is known about cytotoxic and genotoxic effects, reproduction and developmental toxicity, endocrine disruption, and any kind of long-term toxicity and carcinogenicity so far. The present study aims to provide more specific baseline information on the ecotoxicological effects of TMDD in fish. For this end, cyto- and genotoxicity assays were carried out in vitro with the permanent fish cell line RTL-W1; in addition, in vivo studies were conducted with the early life stages of zebrafish (Danio rerio) in order to fill the data gaps in developmental toxicity and endocrine disruption. TMDD showed a cytotoxic and slight genotoxic potential in fish cell lines; moreover, various sublethal and lethal effects could be detected in developing zebrafish embryos. There was no evidence of endocrine-disrupting effects by TMDD; however, mortality following prolonged exposure to TMDD during fish sexual development test was clearly higher than mortality in the fish embryo test after 96-h exposure. Our results thus confirmed previous findings of laboratory screening tests, suggesting short-term toxic effects of TMDD in the intermediate, and long-term effects in the lower milligram per liter range.

The goal was to determine dissolution potency of betulinol and wood sterols (WSs) from pulp and paper mill-contaminated sediments and the current stratification for assessment the load due to potential erosion in the river-like watercourse. Both compounds are wood extractives, which may be toxic to benthos and fish. This research continues a study in which other wood extractives, resin acids and their derivative, retene, were analysed. Sediments were collected from 1, 3.5, 12, 15, and 33 km downstream from the pulp and paper mills, and from 2 upstream reference sites. The dissolution potency into sediment-water elutriates (1 + 4 v/v) was studied by two agitation times and temperatures. The vertical amounts of extractives were determined from the uppermost 20 cm of sediment. The amounts of extractives potentially released were estimated from the sediment layers 0-2 and 2-5 cm by using spatial interpolation. According to the interpolation, the total amount of betulinol and β-sitosterol was calculated as kg/ha in the whole sediment area. Significant concentrations of betulinol (1,666 μg/g, dw) and WSs (2,886 μg/g, dw) were measured from the sediments. According spatial interpolation, the highest calculated amount of betulinol (4,726 kg/ha) and that of the most abundant WS, β-sitosterol (3,571 kg/ha), were in the lake where the effluents were discharged. In the dissolution experiment, the highest concentration of betulinol in sediment (0-10 cm) and elutriate was 412 μg/g (dw) and 165 μg/l, respectively. For WSs, concentrations were 768 μg/g (dw) in sediment and 273 μg/l in elutriate. In a worst-case scenario, betulinol may be desorbed to water in concentrations which are hazardous to aquatic animals. Instead WSs are not a risk in this study area. The amount of desorption varied depending on the concentration of contaminants in sediment, the nature of disturbance, and the sediment organic carbon content.

The environmental acceptability of geotechnical composites made of treated municipal sewage sludge (SwS) and paper ash (PA) after two different curing periods has been investigated. The mineral composition of such composites, including their content of major oxides, is mainly influenced by the PA. The content of potentially toxic elements (PTEs) in the initial materials and in the composites varies considerably. In the SwS the Ba, Cd, Cr, Cu, Hg, Ni and Zn contents are above the legally permitted limits. The PTE content of PA are lower, but still somewhat above the permitted values for Ba and Cu. Mixing these two materials together resulted in a decrease in the PTE, but the Ba, Cu and Zn contents are still too high for agricultural application. However, leachates from composites that had been cured for 28 days are highly alkaline, and the As, Ba, Cd, Cr, Hg, Mo, Ni, Pb and Zn contents in them are well below the permitted values. The Cu contents (2.4 to 5.4 mg/kg) are above the permitted limit for inert material, but inside the range for non-hazardous material. In a leachate of composite which was prepared with fresh PA and a lower PA to SwS ratio, the Cu content was 1.4 mg/kg, since fresh PA is more reactive and therefore has a higher ability to immobilise Cu. Therefore, such mixtures can be utilised for covers and liners for sanitary landfills.

International audience; The authors explored the risks and benefits of repeated irrigation of Populus alba saplings with aqueous paper sludge (APS). Saplings were cultivated in pots of forest soil (3 L) in a greenhouse for 7 weeks and watered twice a week with differing concentrations of APS (0, 10, 20, 30, 50, 75,and 100 % v/v with deionized water). Plant growth and ecophysiological variables along with zinc and aluminum transfer were monitored. A stimulation of plant growth was observed with sludge treatments of 30 or 50 %, significantly correlated to APS input (r = 0.81). This may be explained by the easily available nitrogen as is shown with the positive correlation of CO2 assimilation and leaf nitrogen (r = 0.70). However, a significant reduction in plant growth was observed when treatments of 75 and 100 % of APS were administered, despite a high nutritional level (nitrogen and phosphorus). The study suggests that APS concentrations from 30 to 50 % may positively affect the growth of poplar saplings; however, the higher concentrations indicated a risk for plant growth and the environment.

The mean concentrations of Zn, Cu, Cd, Cr and Fe in mosses around Webuye Pan Paper factory were found to be significantly higher than in controls taken from Kakamega, indicating atmospheric contribution from the anthropogenic activities within the factory, shown within a radius of 1 km around the factory. The mean concentrations (μg/g dry weight) in the mosses ranged from 60.9-124.5, 22.6-34.2, 13.3-14.7, 20.1-33.3 and 1,822.4-2,079.2, respectively. The mean concentrations of Pb in mosses sampled from the eastern and western side of the factory were also significantly higher than in controls. The mean concentrations of Zn, Cu, Cd, Cr, Pb and Fe in topsoil samples ranged from 7 (Pb)-2,310 (Fe) mg/kg dry wt, depending on sample means based on site direction, distance from the factory and season. There was no clear variation in metal concentrations in mosses and topsoils with direction from the factory which was consistent with the observed fluctuations in wind direction which changed from south-west in the mornings to north and south-west in the afternoons during sampling.

Studies on avoidance of contaminants by aquatic organisms verified that such behavior may have crucial ecological implications. Yet, avoidance tests have not been considered in ecological risk assessments. This study aimed at developing a short-term test with Daphnia magna Straus based on avoidance of pulp mill effluents and at comparing its sensitivity to the standard 21 d D. magna reproduction test. The avoidance effective dilution values (12 h EDil20 and EDil50) were as sensitive as the 21 d EDil20 and EDil50 values for reproduction. Therefore, this easily standardizable short-term test can be recommended as a valuable complementary tool in ecological risk assessments. http://dx.doi.org/10.1007/s00128-008-9538-y

Conjugated resin acids (RAs) in fish bile are considered a sensitive chemical indicator of exposure to pulp and paper mill effluent, and were used in this study to monitor the post-spill situation of a lake area (Southern Lake Saimaa) contaminated by black liquor discharged from a mill in June 2003. From the exposure perspective of populations of wild roach and perch, which were studied for their bile RAs at four time periods (July 2003, September 2003, May 2004, July 2004), the exceptional event passed in 2 months or less. Perch had lower concentration of RAs in bile than roach in all sampling areas and all times. Besides the current emissions present in the water column, part of the exposure status of the roach population to RAs seemed to derive from historically contaminated sediments. In order to test this hypothesis, a laboratory experiment with perch and roach, along with three teleosts (rainbow trout, brown trout and whitefish), was conducted. The species were simultaneously exposed for 7 days to RAs (23 microg/l). We calculated a perch/roach-ratio to investigate the difference in origin of exposure between perch and roach populations in the wild and in the laboratory. One year after the spill, the perch/roach-ratio of bile RAs was 0.25 (CV 25%) at 1 km from the mill. This is in contrast to that found under the sole waterborne conditions (0.44; CV 24%), supporting the idea that sediments serve as an additional source of RAs in roach. Additionally, bioconcentration factor log BCF(bile(RA)) was calculated to assess hepatobiliary performance and the capacity to excrete RAs in fish.

We report here on studies designed to asses the effects of paper mill effluents on non-reproductive functions of free-ranging and captive Florida largemouth bass (Micropterus salmoides floridanus). This was accomplished by conducting an outdoor tank study, in which fish were exposed to well water or to 10%, 20%, 40%, and 80% full strength effluent for 28 or 56 days, and by sampling largemouth bass from sites within the St. Johns River, Florida, upstream and downstream from a paper mill plant. Blood and plasma samples from fish from the tank study and from fish sampled from the ambient sites were analyzed for over 20 variables. We also determined liver and spleen weights and examined them histologically. The most significant finding from the tank study was an increase in the concentration of albumin and hepatosomatic index for bass exposed toor = 20% effluents for 56 days. Spleenosomatic index and number of melanomacrophage centers were decreased in bass from effluent-dominated sites (Palatka and Rice Creek), whereas concentrations of calcium, phosphorous, glucose, and creatinine were elevated in fish from these sites, compared to fish from reference streams. Fish from Rice Creek also had fewer red blood cells, and male bass from Palatka had lower concentrations of cholesterol. Plasma concentrations of albumin and hepatic concentrations of glutathione were elevated in males from Palatka, and both females and males from Rice Creek had higher concentrations of globulin. These results indicate a complex pattern of effects of paper mill effluents on several physiological functions. However, despite the myriad of treatment and site-related effects, most physiological parameters fell within normal ranges when compared to reports on largemouth bass and other freshwater species.

The objective of this study was to evaluate the effects of bleached/unbleached kraft mill effluents (B/UKME) on the reproductive parameters of free-ranging Florida largemouth bass (Micropterus salmoides floridanus). The reproductive parameters measured included gonadosomatic index (GSI), histological evaluation of gonads, and plasma concentrations of vitellogenin (VTG), 17beta-estradiol, and 11-ketotestosterone (11-KT). Hepatic ethoxyresorufin-O-deethylase (EROD) activity was measured as a marker of exposure to cytochrome P450-inducing agents in these effluents. Endpoints were compared among adult bass sampled from tributary and mainstream effluent-contaminated and reference sites. Females sampled from the site closest to the mill outfall had a significant five-fold increase in EROD activity compared to bass sampled from reference streams. Although sex hormones were significantly reduced in bass from exposed sites, there were no differences in VTG and GSI across sites. The absence of organism-level responses was probably not related to a lack of sensitivity, as previous studies in our laboratory have shown that bass exposed to these effluents exhibit changes in GSI and in other measures associated with reproductive success. In females, inverse relationships were observed between VTG and GSI and EROD activity. These relationship, however, were not consistent within all of the sites studied. Collectively, our findings indicate that hepatic EROD induction is an effective marker of B/UKME exposure in largemouth bass and that it might be associated with antiestrogenic effects in this species.

Using the standardized polyurethane foam unit (PFU) method, a preliminary investigation was carried out on the bioaccumulation and the ecotoxic effects of the pulp and paper wastewater for irrigating reed fields. Static ectoxicity test had shown protozoal communities were very sensitive to variations in toxin time and effective concentration (EC) of the pulp and paper wastewater. Shannon-Wiener diversity index (H) was a more suitable indicator of the extent of water pollution than Gleason and Margalef diversity index (d), Simpson's diversity index (D), and Pielou's index (J). The regression equation between S eq and EC was S eq = - 0.118EC + 18.554. The relatively safe concentration and maximum acceptable toxicant concentration (MATC) of the wastewater for the protozoal communities were about 20 % and 42 %, respectively. To safely use this wastewater for irrigation, more than 58 % of the toxins must be removed or diluted by further processing. Monitoring of the wastewater in representative irrigated reed fields showed that the regularity of the protozoal colonization process was similar to the static ectoxicity, indicating that the toxicity of the irrigating pulp and paper wastewater was not lethal to protozoal communities in the reed fields. This study demonstrated the applicability of the PFU method in monitoring the ecotoxic effects of pulp and paper wastewater on the level of microbial communities and may guide the supervision and control of pulp and paper wastewater irrigating within the reed fields ecological system (RFES).

The risk analysis was performed to study the bioavailability and eco-toxicity of heavy metals in biochar obtained from pyrolysis of sludge of pulp and paper mill effluent treatment plant. The sludge was pyrolyzed at different temperatures (200-700°C) and the resultant biochar were analyzed for fractionation of heavy metals by sequential extraction procedure. It was observed that all the heavy metals get enriched in biochar matrix after pyrolysis, but the bioavailability and eco-toxicity of the heavy metals in biochar were significantly reduced as the mobile and bioavailable heavy metal fractions were transformed into the relatively stable fractions. Moreover, it was observed that the leaching potential of heavy metals decreased after pyrolysis and the best results were obtained for biochar pyrolyzed at 700°C.

The influence of temperature variation on the humoral immune response using the plaque-forming cell (PFC) assay in freshwater fish Channa punctatus (Bloch) was investigated. The fish was exposed to 1% concentration (v/v in water) of paper and pulp mill effluent under standard laboratory conditions in glass aquaria. Effect of effluent exposure on the organ weight and organ cellularity was also evaluated. In general, lower temperature in winter produced a subdued response in control as well as experimental group. At higher temperature of summer and rainy seasons, an elevated response was observed. It was revealed that though suppressive effect of effluent was evident during all the seasons, in summer, extent of suppression was greater as compared to winter. Paper and pulp mill effluent exposure resulted in a decrease in the splenic and pronephric (head kidney) cellularity, with more pronounced effect in the summer season. We also studied the effects of the length of exposure on various parameters. Fish were exposed for 15, 30, 60, and 90 days to effluent. Short-term exposure for 15 days induced an elevated PFC response, but change was not statistically significant. Conversely, the exposure for 30, 60, and 90 days significantly reduced (p < 0.05-0.001) the PFC response. Long-term exposure also caused significant reduction (p < 0.05-0.01) in the weights of lymphoid organs (spleen, head kidney, and total kidney). These results show a suppressive effect of chemical constituents of paper and pulp mill effluent on the immune functions. Furthermore, results demonstrated that though modulatory effect of the temperature on immune functions is recognized, it was not a major contributory factor to the elevated immunotoxicity of paper and pulp mill effluent in the seasons of high temperature.

Caged common lake mussels (Anodonta piscinalis) have been used in the monitoring of organochlorine compounds in pulp and paper mill recipient watercourses of Finland annually from 1984 to 1998. Statistically significant decreasing trends of chlorophenols and chloroguaiacols originating from chlorobleaching were observed in all recipients in parallel with the decreasing discharges from the mills. Metabolites of chlorophenols, chloroanisoles and chloroveratroles had no or slightly increasing trends. Elevated PCB concentrations were measured in four watercourses. In two areas, PCBs were found to be significantly increasing, in two other cases they showed no trend. A mill producing recycled paper was apparently responsible for an increase of PCBs and DDE in recipient watercourses. Overall decreases were observed for other chlorohydrocarbons except for DDT. Material flows of chlorohydrocarbons were positively correlated with waterflows (Q) in some cases.

Exposure to impaired water quality, as in bleached kraft mill effluents (BKMEs), has recently been demonstrated to impair the ability of fish to elicit an acute stress response. Acute stress caused by catching is, in most field studies, an unavoidable incident that may markedly affect physiological functions. Consistently, dissimilar stress responses to catching procedures in exposed and reference animals may lead to altered results. In this study, juvenile whitefish (Coregonus levaretus) were caged for 30 days in two reference areas and three areas affected by different BKMEs, and the immediate effects of low-level handling on physiological functions in four periods within an hour of the start of the disturbance were clarified. Both primary and secondary stress responses were evident and consistent in fish caged in the two reference areas. Instead, despite the strong cortisol response in fish caged in polluted areas, the secondary stress response was weak or altered with respect to all other measured parameters excluding blood glucose in two of the three polluted areas. Thus, exposed fish may, when compared with reference fish, give different results depending on the exact period from the onset of the catching disturbance to sampling, and therefore, the results may be masked or totally inverted. Because the impacts of acute stress on physiological parameters are immediate and, in exposed areas after low-level handling, dissimilar in nature, this study points to the necessity for time-dependent standardization in field studies whenever sampling is delayed.

Physiological and biochemical biomarker responses were studied in juvenile whitefish (Coregonus lavaretus L. s.l.) exposed experimentally to effluent from the forest industry. The large study area (609 km2), Southern Lake Saimaa, in Southeast Finland, receives 330,000 m3 d-1 of biologically and 55,000 m3 d-1 of chemically treated effluents, discharged from two integrated elementary chlorine free (ECF) bleached kraft pulp and paper mills, from one ECF pulp mill, and from one mill producing unbleached pulp and cardboard. The assessment of exposure to effluent discharged from the mills was based on lake water chlorophenolics (CPs) and resin acids (RAs) measured in samples collected from the 22 experimental sites along the area. Despite the low levels of effluent constituents in the lake, they were still accumulated in detectable levels in fish bile, indicating an exposure to the bioactive compounds of effluents. In comparison to the reference area, a two- to four-fold increase in ethoxyresorufin O-deethylase (EROD) activity was observed in whitefish exposed in the vicinity (1-6 km) of all the mills. However, cytochrome P450 1A1 (CYP1A1) gene expression was increased in only one of the receiving areas, indicating higher sensitivity of the EROD activity in the present study. There were no statistically significant correlations between EROD activity and the ambient water concentrations of the CPs, the RAs, or effluent dilution expressed by water sodium concentration. Neither bile chlorophenolics nor bile resin acids showed a significant correlation with EROD. No significant changes in circulating reproductive steroids, 17beta-estradiol and testosterone, in juvenile whitefish were observed. The vitellogenin gene was expressed in the vicinity of the pulp mill discharging the most wood-derived compounds, i.e. resin acids and wood-sterols, including beta-sitosterol. No differences were observed in plasma immunoglobulin M, glucose, or lactate concentrations between the effluent sources.

Earthworms are ideal soil organisms for use in terrestrial ecotoxicology. As such, several earthworm protocols have been developed for testing toxic potential of chemicals and contaminated soils. Of these, the 48-h filter paper contact (FP) and the 14-d artificial soil exposure (AS) protocols, using mortality (LC50) as the toxic endpoint and Eisenia fetida as the test species, have received the most attention, with the latter being adopted by both OECD and EEC in Europe and the Environmental Protection Agency (USEPA) in the United States. Although the FP technique, adopted by EEC, provides for inexpensive reproducible toxicity screening for chemicals (i.e. establishing relative toxicities), it has been criticized for lacking the ecotoxicological relevance of the AS protocol. Choice of earthworm species for laboratory testing also has been controversial. The manure worm, E. fetida, is criticized for not being sufficiently sensitive to chemicals or representative of {open_quotes}typical{close_quotes} earthworms. Lumbricus terrestris and Apporectodea caliginosa have been suggested as more sensitive and ecologically relevant earthworms by Dean-Ross and Martin, respectively. This paper compares the AS and FP protocols in assessing toxicity of cadminum to L. terrestris and E. fetida using LC50s and LC50s. 19 refs., 2 tabs.

Pulp and paper mill effluents may cause harmful effects to the aquatic environment due to the combined influence of physical factors, toxic compounds, and nutrient enrichment. In the present study, the effectiveness of secondary treatment in reducing the toxicity of an elemental chlorine-free bleached-kraft pulp mill effluent was evaluated. To characterize the toxicity of the effluent, before and after the implementation of secondary treatment, a battery of tests with organisms bearing different functions at the ecosystem level was used, namely Vibrio fischeri (5-min luminescence), Pseudokirchneriella subcapitata (72-h growth), Lemna minor (7-day growth), Daphnia magna (21-day reproduction and 24-h postexposure feeding), Chironomus riparius (9-day growth), and Danio rerio (28-day growth). For the effluent sample collected before the implementation of secondary treatment, P. subcapitata was the most sensitive organism followed by V. fischeri and D. magna, and no toxic effects were observed toward the other organisms. For the effluent sample collected after the implementation of secondary treatment, the effluent caused no toxic effects on any of the tested species. The present results demonstrated not only that secondary treatment efficaciously reduced effluent toxicity toward the selected test organisms but also the usefulness of a battery of tests to characterize the toxicity of pulp mill effluents. published

Two experiments using rainbow trout (Oncorhynchus mykiss) were conducted to examine the combined effects of energy intake as manipulated by ration and pulp and paper mill effluent exposure over either one, or two consecutive reproductive cycles. This study demonstrated that the level of energy intake affected the full range of measured parameters from energy allocation to somatic growth and the gonadal development, steroid production and hematology. Increasing ration level expectedly increased growth, condition, liver and gonad size. Female trout in the higher ration treatments produced more follicles and had larger eggs, investing the same relative proportion of total energy into ovarian development. Sex steroid levels and hematological parameters were also positively influenced by increasing ration level in males and females. By far, the most dramatic impact of reduced ration on reproduction was to substantially reduce the frequency of sexually maturing fish. The effects of effluent exposure were not as marked as those linked to ration level and typically did not manifest unless fish were exposed through two consecutive reproductive cycles. The physiological effects of pulp and paper effluent exposure observed in these experiments were not consistent between the two experiments conducted herein, nor were they consistent with previously observed impacts in similar experiments with this effluent. Effluent exposure over one reproductive cycle did not impact physiological parameters in trout. However, when effluent exposure was maintained over two reproductive cycles, a new pattern of effluent response emerged including increased condition factor in both sexes, a decrease in the potential ability of the blood of females to transport oxygen, and increased sex steroids and reproductive investment in males. Effluent was also observed to cause reduced growth in male trout over two years. The effects of ration on gonad and liver size were far more obvious and consistent when a longer exposure was employed, thus, it appears to take more than one full year for energy intake changes to be reflected in those particular physiological endpoints.

Juvenile zebrafish (Danio rerio) were exposed to different dilutions (0, 0.67, 2.5, 10, and 50%) of effluent water from a Swedish pulp mill that previously has been reported to be androgenic to fish. Exposure was performed between days 10–38 days post-hatch. Fish were sampled for whole-body vitellogenin concentrations at day 38 post-hatch and for histological examination of gonads at day 60 post-hatch. In fish exposed to the highest concentration of pulp mill effluent, elevated concentrations of vitellogenin were measured. The androgenicity of the pulp mill water was confirmed by the increased number of males recorded at 60 days post-hatch. Image analysis of testes indicated stimulation of spennato genesis. Intersex fish were observed in all exposure groups. An androgenic activity equivalent to 5.6 ng/L dihydroxytestosterone was measured using the yeast androgen screen (YAS) assay. The present study demonstrates that both androgenic and estrogenic effects can be detected when exposing zebrafish during the juvenile period to complex mixtures of chemicals.

Experiments were conducted to examine the effects of a thermomechanical (TMP)/bleached kraft pulp and paper mill effluent (BKME), dehydroabietic acid (DHAA), hypoxia, and combinations of hypoxia and effluent on juvenile rainbow trout. In the first two experiments, trout were exposed for 4 weeks to 0%, 10%, 30%, and 70% TMP/BKME or 0, 35, 110, and 250 microgL(-1) DHAA, respectively. Endpoints of those dose-response studies included critical swimming speed, oxygen consumption, and hematology. Reduced swimming performance was found for fish exposed to 70% TMP/BKME. Moderate increases in mean cell hemoglobin concentration at 70% TMP/BKME and blood glucose at 30% and 70% TMP/BKME were also seen. The opposite trend for glucose was found for DHAA-exposed fish, where a slight decrease in glucose was seen at 110 and 250 microgL(-1) DHAA. The third experiment examined the effects of 15% v/v TMP/BKME exposure at 2.5 and 5.0 mgL(-1) dissolved oxygen (DO) for 4 weeks. This experiment found no effect of low DO on swimming ability. An interactive effect between DO and effluent exposure was seen only on hematocrit, where effluent caused an increase in hematocrit at 5 mgL(-1) and a decrease at 2.5 mgL(-1) DO. Effluent exposure in this experiment resulted in a greater number of smaller red blood cells. The current study demonstrated physiological effects in rainbow trout exposed to varying concentrations (15-70% v/v) of a TMP/BKME and no substantial effects of DHAA exposure. With the exception of the reduced swimming performance in fish exposed to TMP/BKME, the observed effects are considered relatively small in magnitude but are occurring at concentrations of effluent that occur in the receiving environment.

The toxicity of intact sediments and sediment extracts, from both an uncontaminated site and a site contaminated by pulp-mill effluents, was tested in a five months study. The deposit-feeding amphipod Monoporeia affinis was exposed in soft-bottom flow-through water microcosms. To examine potential toxicity a set of reproduction endpoints was used including fecundity and different embryo aberrations such as malformed eggs. Among extracts, the aliphatic/monoaromatic and diaromatic fractions along with the total extract were shown to cause the highest toxicity measured as malformed eggs, while the polyaromatic fraction caused toxicity at background levels. A comparison between sediment extracts and pulp mill contaminated intact sediment, however, showed no toxicity of the intact sediment. Thus, the extraction procedure seems to increase bioavailability and subsequently toxicity as compared to the intact sediments in situ. In toxicity testing using fractionated extracts of sediments in a toxicity identification evaluation (TIE) procedures, caution should therefore be taken when assessing bioavailable contaminants in contaminated areas. This should be taken in account both in determining remediation priorities as well as in ecological risk assessments.

Metal pollution of soils is a great environmental problem. The major risks due to metal pollution of soil consist of leaching to groundwater and potential toxicity to plants and/or animals. The objective of this study is to evaluate by means of chemical and ecotoxicological approach the effects of paper mill sludge addition on the mobile metal fraction of polluted metal soils. The study was carried out on acidic soil derived from mining activities and thus polluted with heavy metals, and on two paper mill sludges having different chemical features. The results obtained by leaching experiments showed that the addition of a paper mill sludge, consisting mainly of carbonates, silicates and organic matter, to a heavy-metal polluted soil produces a decrease of available metal forms. The carbonate content seems to play a key role in the chemical stabilisation of metals and consequently in a decrease of toxicity of soil. The leached solutions have a non-toxic effect. The mild remediation by addition of sludge has moreover a lasting effect.

Anadramous Atlantic salmon (Salmo salar L.) returning to Exploits River, Newfoundland, Canada, to spawn encounter low concentrations of thermomechanical pulp (TMP) effluent as they migrate upstream past an integrated newsprint mill. Various physiological responses of adult Atlantic salmon from the Exploits River were studied under laboratory conditions. The effects of a 6-h exposure to 0%, 6%, 12%, or 25% (v/v) TMP effluent or an increasing concentration gradient of effluent (0–25%) on cardiac output ( Q ˙ ) , critical swimming performance (Ucrit), hematocrit, and blood glucose, cortisol, lactate, and osmolality were examined. Relative to other treatment groups, Q ˙ during routine and low-level activity was 7–10% higher in fish exposed to at least 12% effluent. The 25% exposure group had a distinctly lower Ucrit and scope for increase in Q ˙ than the other treatment groups. These findings suggest that effluent exposure elevates physiological maintenance and repair costs, resulting in a reallocation of energetic resources.

Resin acids, a class of wood extractives, are potential toxic constituents in many pulp and paper mill effluents. In the present investigation, the effects of two predominant resin acids, dehydroabietic acid (DHA) and abietic acid (ABA), on survival, reproduction, and growth of the freshwater crustacean Daphnia magna were assessed over its life cycle. Based on the experimentally determined acute toxicity data (48-h EC(50)'s) for DHA (7.48 mg/L) and ABA (7.98 mg/L), D. magna was treated chronically with each resin acid at nominal concentrations of 0, 0.25, 0.5, 1.0, 2.0, 4.0, and 8.0mg/L for 21 days. Both DHA and ABA at concentrations as high as 4.0mg/L did not affect physiological and reproductive parameters such as time to maturation, number of molting, number of broods, and number of offspring produced from surviving daphnids, while significant mortality was observed only at 8.0mg/L in both cases. However, a small but statistically significant decrease in Daphnia growth (body length) at the end of exposure was detected at concentrations as low as 0.5mg/L for DHA and 1.0mg/L for ABA, respectively. These results indicated that both DHA and ABA had the potential to exhibit weak growth inhibition without apparent negative effects on reproduction to D. magna at nonlethal concentration levels. This slight effect is not expected to be ecologically significant because the concentrations of DHA and ABA in biologically treated pulp and paper mill effluents are well below the effective levels observed in the present study.

This study evaluated the potential effects of different concentrations of bleached/unbleached kraft mill effluent (B/UKME) on several reproductive endpoints in adult largemouth bass (Micropterus salmoides). The kraft mill studied produces a 50/50 mix of bleached/unbleached market pulp with an estimated release of 36 million gal of effluent/day. Bleaching sequences were C90d10EopHDp and CEHD for softwood (pines) and hardwoods (mainly tupelo, gums, magnolia, and water oaks), respectively. Bass were exposed to different effluent concentrations (0 [controls, exposed to well water], 10, 20, 40, or 80%) for either 28 or 56 days. At the end of each exposure period, fish were euthanized, gonads collected for histological evaluation and determination of gonadosomatic index (GSI), and plasma was analyzed for 17beta-estradiol, 11-ketotestosterone, and vitellogenin (VTG). Largemouth bass exposed to B/UKME responded with changes at the biochemical level (decline in sex steroids in both sexes and VTG in females) that were usually translated into tissue/organ-level responses (declines in GSI in both sexes and in ovarian development in females). Although most of these responses occurred after exposing fish to 40% B/UKME concentrations or greater, some were observed after exposures to 20% B/UKME. These threshold concentrations fall within the 60% average yearly concentration of effluent that exists in the stream near the point of discharge (Rice Creek), but are above the10% effluent concentration present in the St. Johns River. The chemical(s) responsible for such changes as well as their mode(s) of action remain unknown at this time.

In Taiwan, aquatic toxicity tests for industrial effluents are not required for discharge permits. However, relying on traditional chemical and physical characteristics of an effluent to monitor and regulate such discharges to manage water quality of a receiving water is insufficient. In this study, we used two fish species, Japanese medaka (Oryzias latipes) and tilapia (Oreochromis mossambicus), and three toxic endpoints, including acute and subacute toxicity, to determine toxicity of seven different types of industrial effluents. Prior to the study, two reference toxicants were tested on two fish species. The LC50s of CdCl2 for tilapia and medaka juveniles were 29.6 +/- 15.3 mg/L and 2.2 +/- 1.2 mg/L, respectively. The sensitivity of medaka embryo mortality and hatching inhibition to CdCl2 were about the same, with the LC50 and EC50 of 0.3 +/- 0.1 mg/L and 0.1 +/- 0.1 mg/L, respectively. The LC50s for tilapia and medaka juveniles to sodium dodecyl sulfate (SDS) were 19.7 +/- 10.6 mg/L and 12.5 +/- 5.9 mg/L. The medaka embryo was less sensitive to SDS than to CdCl2. The embryo's LC50 for SDS was 5.8 +/- 2.8 mg/L and the hatching inhibition EC50 was 1.3 +/- 1.1 mg/L. Results of toxicity tests on different effluents showed that the electroplating effluent was the most toxic, followed by acrylonitrile manufacturing and pulp/paper mill discharges. The LC50s of the electroplating effluent to different assays were in the range of several percents of the whole effluent. The pulp/paper effluent was toxic only to the medaka embryo. The rest of the industrial effluents tested showed either moderate or no toxicity to the animals.

Samples of effluents, sludge, pulp, final products (paper) and soil were collected from the identified pulp and paper mills in India. The samples were analysed for 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and other dioxin congeners and precursors. Pulp and paper mills using chlorine for the bleaching process showed the presence of 2,3,7,8-TCDD in effluent samples. In the effluent and pulp samples from mills where chlorine dioxide was used as a bleaching agent, the 2,3,7,8-TCDD congener ranged from below the detection limit 0.05 to 0.12 ngL(-1)/ngg(-1). The relative standard deviation of reproducibility and the percent recovery of 2,3,7,8-TCDD were 2.07 and 82.4% in pulp and 2.8 and 92% in effluent, respectively. The 1,3,6,8-TCDD was the only other major dioxin congener found in the treated and untreated effluent and sludge samples. However, dichlorobenzene, trichlorophenyl, and hexachlorobiphenyl were detected in all samples. The formation of dioxins can be minimised by replacing chlorine with chlorine dioxide in bleaching processes in pulp and paper mills.

An investigation was made of cytochrome P4501A (CYP1A) induction, determined by the activity of EROD (7-ethoxyresorufin O-deethylase), and formation of benzo[a]pyrene-diolepoxide-DNA (BPDE-DNA) adducts, measured by synchronous fluorescence spectrophotometry, in liver microsomes of perch (Perca fluviatilis), bream (Abramis brama), and roach (Rutilus rutilus). Fish were collected from the southern part of Lake Saimaa (Finland), an area polluted by effluents from the pulp and paper industry. In addition, two conjugation enzymes (UDP-glucuronosyltransferase and glutathione S-transferase) were determined. Overall, when compared to an upstream reference, EROD activity was higher in fish at waters downstream of the mill sewer. In bream EROD activity was threefold and in roach twofold. The changes in conjugation enzymes were not clearly related to the pollution gradient. The formation of BPDE-DNA adducts by liver microsomes was in correlation to both the pollution gradient and the EROD activity. This implies that CYP1A enzymes may play an important role in carcinogen activation in natural fish populations and that the formation capacity of DNA adducts may be a useful indicator when evaluating the potential toxicity of industrial water pollution.