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It has previously been shown that trichloroethylene (TCE) soot extracts cause dioxinlike toxic effects in medaka fish (Oryzias latipes) and primary liver cell culture of rainbow trout (Oncorhynchus mykiss). This study examines embryonic and larval induction of cytochrome P450 1A and stress proteins after exposure of medaka embryos to extracts and fractions of TCE combustion-generated aerosols. Embryos were exposed to three concentrations of whole soot extract (WE; 2.7, 7.2 and 18 μg l-1 incomplete combustion byproducts), TCDD (2,3,7,8-tetrachlorodibenzo- p -dioxin, 3 ng l-1) and four TCE fractions with different polarity (Fr 1-4; 18 μg l-1) for 8 days. Approximately 50% of the embryos were then transferred to control water and allowed to hatch. EROD activity in embryos was significantly higher than in controls after the 8 day-exposure to TCE soot extract (WE), with activity being highest at 2.7 μg l-1 WE (5.6× control). Of TCE fractions, only fraction 1 (Fr1, non-polar compounds) caused a significant increase in EROD activity. In larvae, significantly induced EROD activity was detected following the 7.2 μg l-1 WE treatment (3.30 pmol min-1 mg prot. -1). Dioxin treatment did not result in increased embryonal or larval EROD activity.Larval CYP 1A was localized mainly in liver, gut, kidney,cornea and chondrocytes of cranium and tail. Hsp70 was induced in larvae but not in embryos. Statistically significant induction over controls was observed in two WE groups (2.7, 7.2 μg l-1) and in the group exposed to dioxin (WE 18 μg l-1 not analysed). Mean hsp60 levels were not significantly higher than controls. Apparent bacterial contamination may have induced hsp70 in one control group including embryos and larvae (C/Fr3). [ABSTRACT FROM AUTHOR]

To corroborate the responses in whitefish (Coregonus lavaretus L.) exposed to elemental chlorine free (ECF) bleached-kraft pulp mill effluent (BKME) in situ. a 30-d laboratory exposure was carried out at concentrations simulating the field conditions. The flow-through exposures were conducted at four secondary (activated sludge) treated effluent (STE) concentrations: 1.3, 2.3, 3.5, and 7%. To evaluate the roleof the secondary treatment, fish were also exposed to one concentration (3.5%) of pretreated effluent (PTE) from the mill. Compared to the control, whitefish liver 7 -ethoxyresorufin-O-deethylase (EROD) activity was twofold in fish exposed to 3.5% STE, which was similar to monooxygenase induction in the field at the same effluent dilution. The exposure to 3.5% PTE caused a 12-fold relative induction in whitefish. The activity of pentoxyresorufin dealkylase showed a high correlation with EROD activity (r2 = 0.85, p < 0.01). The plasma concentration of 17Beta--estradiol was reduced by 37% (p < 0.05) in fish exposed to 3.5% STE, whereas testosterone was reduced by about 40% (p < 0.05) in fish in both 3.5% STE and PTE groups. The accumulation of chlorophenolics (CPs) and resin acids (RAs) in the bile of the fish was negligible at the three lowest STE concentrations, reflectingthe nearly nondetectable levels of CPs and RAs in secondary treated whole effluent. The measured blood parameters plasma immunoglobulin M, glucose, hemoglobin, and hernatocrit were not affected by effluent exposure. The responses obtained from the laboratory simulation well accorded with the exposures in the field, although signs of reproductive impairment could be detected in the laboratory. Overall, however,it is evident that the improvements to mill processes and wastewatertreatment have substantially reduced the load of harmful constituents in bleached-kraft mill effluent and biological impacts in the receiving environment. [ABSTRACT FROM AUTHOR]

Physiological and biochemical biomarker responses were studied in juvenile whitefish (Coregonus lavaretus L. s.l.) exposed experimentallyto 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 fromtwo 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-foldincrease 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 theEROD 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, ie. resin acids and wood-sterols, including beta-sitosterol. No differences were observed in plasma immunoglobulin M,gluc [ABSTRACT FROM AUTHOR]

Extracts of effluents and sludges from the primary and secondary clarifiers of an activated sludge treatment plant at a Finnish bleached kraft pulp and paper mill were analyzed in two cell bioassays. Total dioxin-like activities were determined by measuring the induction of ethoxy resorufin-0-deethy lase (EROD) activity in Hepa-1 mouse hepatoma cells. Estrogenicity was studied by measuring luciferase activity in MCF-7 ERE-luc. which are MCF-7 human breast cancer cells stably transfected with an estrogen- responsive element linked to a luciferasepromoter Sediments collected near the pulp mill and from other sitesin Lake Saimaa as well as fillets of whitefish exposed to effluents were examined and EROD activity was determined for complex mixtures of compounds extractable with dichloromethane (DCM) from the pulp milleffluent or compounds collected by semipermeable membrane devices (SPMDs) from the same effluent. Extracts of effluents, particulates, SPMDs, and sludges all caused measurable EROD induction. Because the induction potencies of the total DCM extract and the fraction of neutral compounds were similar, it was concluded that most of the EROD induction in pulp mill effluents was due to neutral compounds. Sediment collected from the vicinity of the pulp mill had greater EROD-inducingpotency compared to that of the control sites from the same lake. Induction of EROD potencies of muscle extracts of whitefish exposed to diluted effluents were not significantly greater than those of control fish exposed to dilution water only. All extracts contained some estrogen agonist activity when tested in the MCF-7 bioassay. [ABSTRACT FROM AUTHOR]

Biomarkers in the earthworm Aporrectodea tuberculata (Eisen) were measured to find out their possible induction under Cu and Zn exposure and differences in the responses between two populations with different exposure history. The biomarkers applied were concentration of metallothioneins (MT), and cytochrome P4501A (CYP1A) monooxygenase and glutathione-S-transferase (GST) activities. These were measured from earthworms sampled at three distances from a steel smelter in Finland and from the individuals from two populations, one with and another without earlier metal exposure, exposed to three combined Cu/Zn concentrations in the laboratory. In the field, MT concentration, and cytochrome CYP1A and GST activities decreased with increasing distance from the smelter. In the laboratory, biomarker responses varied in relation to the duration and level of exposure, and they were also dependent on the population. The endpoints appeared to be analytically reproducible and sensitive parameters in A. tuberculata, and thus, they can be used in ecotoxicological field monitoring and in experimental research in the laboratory.

The attenuation of solar ultraviolet (UV) radiation in five lakes in Central Finland was evaluated through field measurements and/or by determining the optical properties of the lake water during summer 1999. Spectral UV irradiance in the air and at several depths underwater was measured in three lakes (Lake Palosjärvi, Konnevesi, and Jyväsjärvi) with dissolved organic carbon (DOC) ranging from 4.9 to 8.7 mg l(-1) and chlorophyll a ranging from 1.6 to 16 g l(-1). According to the field measurements, 99% of the UV-B radiation was attenuated in approximately a half meter water column in the clearest lake. In the UV-A region at 380 nm, the corresponding attenuation occurred in the upper one meter. In a small humic lake (DOC 13.2-14.9 mg l(-1)) UV-B radiation was attenuated to 1% of the subsurface irradiance within the top 10 cm water column, whereas UV-A radiation (at 380 nm) penetrated more than twice as deeply (maximum 25 cm), as predicted from the absorption coefficients. These results suggest the importance of the dissolved fraction of lake water in governing the UV attenuation in lakes. This was seen from the significant relationship between the vertical attenuation coefficients (Kd) based on field measurements and the absorption coefficients (ad) derived from spectrophotometric laboratory scannings, as well as between Kd and DOC.

Exposure to biologically treated bleached kraft mill effluent (BKME) is demonstrated to greatly modify the acute physiological stress response in fish and, accordingly, to lead to inconsistencies in data interpretation due to dissimilar effects of handling procedures on reference and exposed fish. To consider this phenomenon, juvenile whitefish (Coregonus lavaretus) were caged for 30 days in four reference sites and in three areas influenced by different BKME discharges. After exposure, fish were subjected to the impacts of low-level handling by raising the cages to the water surface, serially handnetting the fish, and transferring ( approximately 10 min) the submerged cages to the research vessel. The data on physiological variables were pooled within each area to three groups according to the periods (<4 min, 10-20 min, 21-40 min) from the onset of handling to the sampling of individual fish. BKME-exposed whitefish sampled during the first period exhibited lower plasma cortisol and blood lactate levels and higher red blood cell Na+ concentrations than reference fish sampled during the same period. In reference whitefish, along with increased plasma cortisol and blood lactate levels, gill ATPase activity as well as liver glycogen and blood glucose levels were markedly affected by the handling procedure, while the latter three responses were strongly attenuated in exposed whitefish. Red blood cell Na+ and K+ and blood hemoglobin responses vanished in only one mill area. These findings, in accordance with similar results of earlier studies dealing with the same species, point to the need for this kind of time-dependent approach to achieve reliable and comparable outcomes in field experiments and encourage work on determining the importance of functional deviations noted in fish exposed to anthropogenically modified water qualities.

The effects of UV radiation on the acute toxicity of retene (7-isopropyl-1-methylphenanthrene) to Daphnia magna Straus were studied. Dehydroabietic acid (DHAA) from which retene is formed in the vicinity of pulp and paper industry was also studied. Pyrene, anthracene, and phenanthrene were used as model PAH compounds. The time taken for immobilization (ET50) was monitored under biologically effective UV-B dose rates of 240, 365, 565, and 650 mW m(-2) (UV-A and visible light also present). Median effective concentrations (EC50) were determined after a 15-min UV exposure (565 mW m(-2)) followed by 24 h in the dark. Retene (10-320 microg l(-1)) was not acutely toxic in the dark. The induction of phototoxicity was in agreement with the absorption properties of the compounds (absorption peak of retene at around 300 nm). Photoinduced toxicity followed an order pyrene > anthracene > retene. Phenanthrene and DHAA were not acutely phototoxic. Accumulation of the compound in Daphnia before UV exposure was essential. Some changes in the absorption spectra of the compounds were seen after a 5-h UV irradiation (565 mW m(-2)), but none of the irradiated compounds were acutely toxic without further UV exposure. Therefore, the enhanced acute toxicity was primarily due to internal photosensitization reactions rather than photomodification. The dissolved fraction of 25% pulp and paper mill effluent reduced phototoxicity by attenuating UV radiation. The phototoxicity of retene was a function of both the exposure concentration and the UV-B dose rate, but relatively high UV-B dose rates and concentrations were needed for the acute photoinduced toxicity.

The mechanisms and dose-response of UV action on the early development of Macrocystis pyrifera (L.) C. Agardh gametophytes were investigated. Post-release, zoospores undergo germination, germ tube elongation, DNA synthesis, nuclear division and translocation, which were followed for 41 h under laboratory conditions. The spores were exposed to UV radiation before germination (3 h post-release) or before nuclear division (20 h post-release). Biologically effective UV-B doses (BEDDNA300 nm) higher than those used in the experiments are needed for a 50% inhibition in germination (BED50 > 1600 J m-2). Nuclear division/translocation was more sensitive to UV radiation. When the spores were cultured in the dark, UV exposure at both 3 and 20 h post-release resulted in a dose-responsive inhibition of nuclear division/translocation (BED50 64 and 86 J m-2). Culturing in the light indicated recovery in the spores that were irradiated at 3 h post-release (BED50 356 J m-2), whereas no light-dependent recovery occurred within 41 h of culture when irradiated at 20 h post-release (BED50 80 J m-2). The results present a possible mechanism of UV inhibition in early life stages of the giant kelp, suggesting that environmentally relevant UV-B levels can perturb or delay the development and recruitment of the gametophytes by inhibiting nuclear events.

Penetration of UV radiation into Finnish lakes was evaluated through field measurements and/or by determining the optical properties of the lake water. The spectral measurements of air and underwater irradiance (280-400 nm) were performed in early September, 1998, in four lakes (Lake Konnevesi, Tuomiojärvi, Jyväsjärvi, and Kopru) representing a variety of humic (DOC 8.1-16.0 mg l-1) and chlorophyll (2.3-14 micrograms l-1) concentrations. A linear relationship was found between vertical attenuation coefficient (Kd) and DOC (r2 > 0.75), whereas no relationship between Kd and chlorophyll a was observed (r2 < 0.20). The depth where the UV-B irradiance is 10% of the value just beneath the surface (z10%) ranged 5-19 cm. Kd based on field measurements, and absorption coefficient (ad) derived from spectrophotometric scanning measurements of filtered lake water showed a linear relationship (r2 = 0.93). Kd values for two lakes where field measurements were not made (DOC 4.2-5.2 mg l-1, chlorophyll a 1.7-1.9 micrograms l-1) were obtained from the relationship between Kd and ad, giving the 10% UV-B penetration depth of 1.3 m to Lake Kuorinka and 0.21-0.24 m to Lake Palosjärvi.

Juvenile whitefish (Coregonus lavaretus L. s.l.) were exposed by caging in the field to diluted effluents from three operating pulp, paper, and paperboard mills in Southern Lake Saimaa, Finland. The expression of the vitellogenin gene, used as a biomarker of estrogenic contamination of effluents, was measured using a Northern blotting method. Increased mRNA levels, the most specific and reliable evidence for estrogen receptor-mediated actions in vivo, were found in fish caged in the vicinity of one of three mills studied. This mill was found to discharge wood-derived compounds, such as sterols and resin acids, into Lake Saimaa in amounts considerably exceeding those from the other two mills. The increased vitellogenin gene expression suggests that the effluent is a source of estrogenic contaminants., (Copyright 1999 Academic Press.)

Lipophilic organic compounds originating from kraft pulping and papermaking were identified by straight gas chromatography/mass spectrometry (GC/MS) analyses. Samples analyzed included a primary clarifier effluent (PE) and a secondary clarifier effluent (SE) from the activated sludge treatment plant of a Finnish ECF-bleached (Elementally Chlorine Free) kraft pulp and paper mill. Liquid-liquid extraction composition of PE was compared with solid phase extraction (SPE) and dialysis of a semipermeable membrane device (SPMD) exposed to PE. Dichloromethane extracts of particulate material isolated from PE, sludges from both the primary and secondary clarifier, a sediment collected in the vicinity of the mill and whitefish subacutely exposed to the secondary treatment effluent were also investigated. Typical pulp mill-related compounds such as terpenes, terpenoids and aromatic compounds were identified in PE whereas these were non-detectable in SE. For example, thunbergene, thunbergol, squalene, longifolene and derivatives of abietic acid were observed in PE. Alkylated polycyclic aromatics were major compounds identified in the sediment sample with retene (C4-alkyl phenanthrene) as a predominant component.