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1.
The effluents from bleached Kraft pulp mill (BKME) and paper industry are toxic to different aquatic organisms being an important source of contamination to aquatic environments due to the presence of several chemicals produced during the production of Kraft pulp. The main objective of the present study was to evaluate the exposure effects of a secondary-treated BKME in two different species of fish: Carassius auratus and Dicentrarchus labrax. Both species were exposed to different concentrations of secondary-treated effluent (1%, 10%, 25%, 50%, 100%) in semi-static tests under controlled laboratory conditions. At the end of the experimental period (21 days), samples of livers were collected for CYP1A determination and histopathological evaluation. The results show significant changes (p?<?0.05) of CYP1A induction in carp exposed to 50% and in sea bass exposed to 25% of the effluent. Histopathological alterations were also observed according to the different concentrations of the tested effluent suggesting that tested BKME cause damage to exposed organisms.  相似文献   

2.
The total inventory and distribution of ExtractableOrganic Chlorine (EOCl) has been investigated in anestuary exposed to pulp mill effluents for over 50 yr.The estuarine turnover of suspended particulate matter(SPM) and associated pollutants was studied using a modeldescribing important processes for EOCl accumulation. Therecipient has a low retention of SPM due to dominatingstratified conditions in the water column. The totalinventory of EOCl in the sediment is therefore relativelylow as compared with the total discharge. It was foundthat the vertical distribution of EOCl has a closerelationship to the extent of chlorine use at the mill.Discharges of SPM from the pulp production process play amajor role in establishing the chronology of the sediment.A modernisation of the mill from 1986 to 1991 considerablyreduced the discharges of chlorinated substances. In the near future there will be an accumulation of EOCl in the estuary.  相似文献   

3.
A method was developed to fractionate chloride ions from complex effluents using an ion exchange column. The procedure utilizes a strongly basic anion exchange resin with hydroxide ions as the exchange ion. The chloride within the effluent is exchanged for hydroxide which is less toxic to Ceriodaphnia dubia. The addition of hydroxide to the solution requires a pH adjustment to a physiologically acceptable pH for Ceriodaphnia with an acid. The fractions are added to Ceriodaphnia and the ET 50 (median lethal time) determined. The column was applied to two effluents with suspected chloride toxicity. The column successfully removed virtually all of the chloride from the effluents. A significant reduction in toxicity was found following the process for one of the effluents. In addition, a control that consisted of the original effluent at the ionic strength of the column fractions revealed that chloride was a causative toxicant in both of the effluents.  相似文献   

4.
An optimized co-precipitation process for color removal from Kraft pulp and paper mill effluents is described. The process involves sequential addition of alum and lime under controlled conditions, as well as the influence of selected polyelectrolytes on the degree of color removal. Results obtained were in the range of 86 to 95% removal for caustic extract effluent and whole mill effluent. An Al+3/Ca+2 ratio of 0.23 gave optimal results with a final pH in the 4 to 5 range. The chemicals used in the suggested process are commonly available in most Kraft mills. As well, significant reductions in chemical oxygen demand (COD) were observed during the color removal process. An economic analysis indicates that the process is financially attractive.  相似文献   

5.
Over a one year program of intensive monitoring of effluents from Ontario Hydro's nuclear, fossil and hydroelectric generating facilities, theDaphnia magna and rainbow trout,Oncorhynchus mykiss, acute toxicity tests correlated well, with 61 % of the toxic effluents toxic to both species. If the effluent was toxic to only one of the test species it was generally toxic toD. magna, with from 23 to 57% of the toxic effluents toxic toD. magna only. The greater sensitivity ofD. magna to boiler blowdown effluent likely resulted from a combination of the low conductivity of boiler blowdown effluent and the smaller size and greater surface to volume ratio ofD. magna relative to rainbow trout.D. magna were also particularly susceptible to oil/water separator samples, with the daphnids frequently observed to be caught at the surface/water interface. These observations suggest that an accumulation of organic material at the air/water interface was responsible for the mortality ofD. magna. In subsequent tests, we also examined the relationship between theD. magna acute toxicity test and a bacterial-based assay (Toxi-Chromotest®) for several toxic effluents from Ontario Hydro stations to determine if bacterial-based tests could provide similar information in less time with smaller sample volumes. TheD. magma acute toxicity test did not correlate well with the bacterial-based Toxi-chromotest®. In particular, many of the samples which were toxic toD. magna were not toxic to the Toxi-chromotest® assay. The poor correlation between theD. magna and Toxi-chromotese® likely relates to both the relatively low toxicity of many of the effluent samples, and the fact that in many cases toxicity likely resulted from relatively simple combinations of inorganic toxicants. Accordingly, the Toxi-Chromotest® assay would not seem suitable as a surrogate for theD. magna acute toxicity test for our effluents.  相似文献   

6.
Chemistry of effluents entering natural water bodies is usually ecological chemistry. The object of its study is the influence of effluents on chemical and biological processes of self-purification. Mercury and its compounds are priority pollutants in bleached kraft pulp mill effluents. It is ascertained that Hg enters the effluents from wood and auxiliary reagents: compounds of Na and active Cl and also from H2SO4 employed for neutralization of effluents before biological treatment. At the investigated enterprise the effluents have three stages of treatment: biological, physico-chemical and mechanical. This treatment reduces the Hg concentration in effluents from 10 to 30 ppb to 0.3 to 0.5 ppb. No increased Hg accumulation by aquatic organisms and bottom sediments in the area of effluent discharge was found. Moreover, aquatic organisms grown during 1 mo in the effluents medium did not accumulate Hg in comparison with the control animals. It is found that such ecological effect is obtained as a result of inclusion the modern physico-chemical methods into the complex treatment system.  相似文献   

7.

Purpose

In order to assess possible adverse effects originating from pulp deposits in a Swiss lake, a sediment quality triad approach was applied with chemical, ecotoxicological and ecological assessment methods.

Materials and methods

To obtain an integrative picture of the potential ecotoxicological effects on organisms of different trophic levels, four test procedures were applied. The acute effects of pulp deposit pore water on a decomposer, the amphipod Gammarus fossarum, were monitored. Chronic toxicity of the pore water was evaluated on primary producers via a growth inhibition test with unicellular green algae (Pseudokirchneriella subcapitata) and on secondary consumers in a reproduction test with the water flea Ceriodaphnia dubia. To evaluate the effects of the pulp deposit on sediment inhabitants, a whole-life-cycle test with the non-biting midge Chironomus riparius was undertaken. Chemical assessment included dissolved organic carbon, extractable organic halogenic compounds, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and heavy metals. The composition of the macrozoobenthos community was analysed in order to assess the ecological effects.

Results and discussion

G. fossarum displayed increased locomotor activity at 12.5% but not at 25% sample concentration during a short-time exposure of 20 h. Chronic effects compromised the reproduction and growth of C. dubia (lowest observed effect concentration, 12.5% sample concentration) with zero population growth in 100% pulp deposit pore water. In 100% pulp deposit, C. riparius exhibited increased mortality at 10 and 17 days after oviposition. Pulp deposits of 50% and 100% concentration caused a significantly lower emergence compared with the reference treatments (lake sediment and quartz sand). Additionally, the locomotor activity of chironomids decreased significantly in 25–100% pulp deposit. No chronic effects of pulp deposit pore water on algae photosynthesis and growth could be detected. The bioassay results were in accordance with an elevated content of PAHs, PCBs and metals in the pulp deposit. Significantly more organisms known to be tolerant to organic pollution were present within the macrozoobenthos community.

Conclusions

In general, for sediment inhabitants such as chironomids, the pulp deposit has to be classified toxic. In the present test setup, the toxicity of the pulp deposit was reflected better by the chronic test systems applied than by the acute ones. The applied testing framework could be a suitable tool to assess the risk of contaminated sites, and this information will help decide whether risk mitigation measures should be taken. In addition, with a similar approach, the success of any mitigation measures taken can be assessed.  相似文献   

8.
This paper presents the results of using a pilot-scale-constructed wetland as a tertiary system to simulate the treatment conditions of wastewater effluents from the metal-mechanical industry, aiming to achieve the Brazilian legal standards of phosphorus and nitrogen emission. The macrophytes were placed in 1 m3 polyethylene tanks, daily estimating the treatment of 2 m3 of effluents. The effluents were circulated in a horizontal subsurface flow through a porous matrix of thick sand and gravel, in which the roots of the macrophytes of the species Reed (Scirpus sp.) and Cattail (Typha sp.) were fixed. Monitoring of the pilot plant was performed through a battery of physical?Cchemical and biological analyses. Despite the load variations and operational problems, the system presented a positive degree of pollutant efficiency removal, especially for phosphorus (73% medium), TKN (61% medium), and NH4?CN (56% medium). Peak results were achieved during the last 3 months of monitoring. The chemical analysis of the support layer, plus the root system and aerial portion of the plants, revealed that these wastes could be used as fertilizer.  相似文献   

9.
Recently, there has been increasing concern about perfluorinated compounds, especially perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) due to their biotic and abiotic persistence and chronic toxicity. To characterize the spatial distribution and seasonal variation of PFOS and PFOA in the aquatic and oceanic environment of Singapore, more than 100 water samples from reservoirs, rivers/canals, coastal waters, and treated effluents of wastewater treatment plants (WWTPs) were collected and analyzed in this study. Solid-phase extraction followed by high-performance liquid chromatography (HPLC) coupled with tandem MS (HPLC/MS/MS) was applied to quantitatively identify PFOS and PFOA. PFOS concentrations in surface waters, wastewaters and coastal waters were in the range of 2.2?C87.3 ng/L, 5.8?C532 ng/L, and 1.9?C8.9 ng/L, respectively, while those of PFOA were 5.7?C91.5 ng/L, 7.9?C1,060 ng/L, 2.4?C17.8 ng/L, respectively. Compared with surface waters and wastewaters, coastal waters had lower concentrations of PFOS and PFOA. Highest concentration of PFOA (532 ng/L) and PFOA (1,060 ng/L) were observed in treated effluents of two WWTPs. Our results suggest that coastal waters in the western area of Singapore are more heavily contaminated than those in the middle and eastern areas. The release of effluents from WWTPs is an important pathway by which perfluorinated compounds enter the oceanic environment. Between dry season and wet season, significant seasonal differences (p?=?0.025) were observed in surface waters for PFOS only, while no discernable seasonal differences were found for both PFOS and PFOA in coastal waters and wastewaters.  相似文献   

10.
We compared arbuscular mycorrhizal (AM) and dark septate endophyte (DSE) fungal associations in 2 crops and 31 weeds commonly occurring in pulp and paper mill effluent irrigated and well-water irrigated soils. Soil pH, organic C, N, P and K, were higher in pulp and paper mill effluent irrigated than in well-water irrigated soils. In contrast, the average AM fungal colonization, root length with AM fungal hyphae/hyphal coils, spore numbers and diversity were lower in pulp and paper mill effluent irrigated soils compared to well-water irrigated soils. However, no significant variation was found in DSE fungal colonization nor root length with AM fungal arbuscules/arbusculate coils and vesicles between pulp and paper mill effluent irrigated and well-water irrigated soils. A significant negative correlation existed between AM and DSE fungal colonization in both effluent and well-water irrigated soils. Twelve AM fungal spore morphotypes belonging to Acaulospora, Dentiscutata, Glomus, Racocetra and Scutellospora were isolated from the well-water irrigated soils, whereas spores of six morphotypes were isolated from effluent irrigated soils. AM fungal spore numbers were correlated significantly and positively to AM fungal colonization in effluent and well-water irrigated soils.  相似文献   

11.
Assessment of genetic variability in the available germplasm is the prerequisite for development of improved genotypes through planned breeding programmes. In view of this, 39 “hatkora” (Citrus macroptera Mont.) genotypes collected from different locations of Mizoram, India were evaluated for physico-chemical characteristics during 2013–2015. The study reveals that there was significant variation among the collections in these particular traits. Individual fruit weight ranged from 277.78 to 617.69 g; fruit diameter 9.32–12.52 cm; fruit length 7.74–10.19 cm, fruit volume 238.33–583.33 cc; pulp weight 153.75–320.94 g; pulp:peel ratio 1.50–3.24 and seed number 9.33–23.6. Similarly, the chemical parameters also varied significantly among different germplasms. The juice content varied from 13.45 to 32.53 %, ascorbic acid 34.81–73.64 mg/100 mL, TSS 6.15–9.10 %, acidity 5.03–8.75 %, total sugars 5.16–7.97 % and sugar:acid ratio 0.75–1.52. From the analysis of genetic parameters, it could be concluded that characters like fruit weight, fruit length, fruit diameter, fruit volume, pulp weight, pulp–peel ratio, juice, Total soluble solids (TSS), acidity, ascorbic acid, total sugars, and sugar–acid ratio could be used as selection criteria for development of effective and productive plant types in “hatkora”. Wide range of variation in physico-chemical parameters of “hatkora” fruits indicated the great scope of individual plant selection based on these characters for future genetic improvement programme.  相似文献   

12.
Decolorization of six synthetic dyes and two raw textile effluents (A and B) by eight basidiomycetous fungi was investigated. Among eight basidiomycetous fungi, fungal isolate RCK-1 decolorized textile effluent A maximally (42%), while fungal isolate RCK-3 was found to decolorize more of Congo Red (69%), Xylidine Ponceau 2R (100%), Poly R-478 (96%), Indigo Carmine (99%), Lissamine Green B (90%), Toluidine Blue (57%) and textile effluent B (54%), than the rest of fungi. Percentage decolorization of all synthetic dyes and textile effluents by the new fungal isolates RCK-1 and RCK-3 was higher compared to the most widely studied simultaneous lignin degrader, Phanerochaete chrysosporium and selective lignin degrader, Pycnoporus cinnabarinus, when tested in liquid cultures. A statistically significant positive correlation between laccase production and decolorization of dyes and effluents was obtained as compared to other ligninolytic enzymes (lignin peroxidase and manganese peroxidase) production. This showed the importance of the differential contribution of the different ligninolytic enzymes towards the decolorization of the synthetic dyes and textile effluents. The substantially higher ligninolytic enzyme production by the fungal isolates RCK-1 and RCK-3 also suggested their potential use for textile effluent treatment and other possible biotechnological applications.  相似文献   

13.
Paper mill residuals may beneficially be used to improve the fertility of tropical acid soils. The effects of paper pulp on soil pH, exchangeable Al and soil solution composition of three acid tropical soils were compared with the effects of equivalent rates of lime in two batch experiments. Paper pulp was more effective than lime in increasing soil pH. However, both amendments were equally effective in decreasing exchangeable Al. Paper pulp and lime similarly influenced the composition of the soil solution by increasing soil solution pH, dissolved organic carbon, inorganic carbon, NO3, SO4, Ca and Mg. The supply of nitrate by the soil, however, was reduced in paper pulp treatments compared to lime treatments. Nitrate had a major role in controlling nutrient concentrations in the soil solution. Reduced NO3 concentrations in paper pulp treated soils compared to limed soils could therefore result in lower nutrient availability and limited losses by leaching.  相似文献   

14.
In order to assess as to whether treated textile effluent could be safely used to irrigate some winter vegetables, growth room experiments were conducted. Varying levels of treated and untreated textile effluents were applied to germinating seeds of some winter vegetables and their effect was evaluated on germination and early growth stage using seed germination, growth, and biochemical attributes. From the results, it was obvious that textile effluent reduced seed germination and early growth of all vegetables. However, this effect was more pronounced at the highest concentration of textile effluent. Furthermore, treated textile effluent did not show any inhibitory effect on seed germination of all vegetables. Photosynthetic pigments such as chlorophyll a and b, and protein contents were higher in the leaves of all vegetable plants irrigated with treated textile effluent than those of supplied with untreated textile effluents. It has been observed that heavy metals were lower in concentration in treated textile effluent as compared with untreated textile effluent. However, germination and growth responses of all three vegetables were different to treated or untreated textile effluents. Furthermore, the Raphanus sativus ranked as tolerant followed by Brassica campastris and Brassica napus based on germination and growth responses. In conclusion, in view of shortage of water, textile effluent could safely be used for irrigation to vegetables after proper processing.  相似文献   

15.
Availability and plant uptake of nutrients were evaluated in three tropical acid soils (Kandiudult) amended with paper pulp and lime under greenhouse conditions. Amendments were applied to attain target pH values of 5.5, 6.0, and 6.5. A control treatment (no paper pulp or lime added) was also included. Rye grass (Lolium perenne L.) as a test plant was grown for three successive cycles of 40 days each. Extractable nutrients and cumulative nutrient uptake were determined. The application of paper pulp or lime resulted in a significant increase in exchangeable Ca and K and a decrease in exchangeable Mg and extractable Fe, Mn, and Zn. Amendment of soils with paper pulp or lime increased plant uptake of Ca and Mg and decreased that of K, Mn, and Zn. Both amendments behaved similarly, but the effect of lime seemed generally greater than that of paper pulp. Paper pulp in tropical acid soils behaved as a liming agent rather than an organic amendment. Similar to lime, amendment of soils with paper pulp resulted in an increase in availability of Ca and Mg and in a decrease in availability of K, Mn, and Zn for plants. Soil extractions appeared to be appropriate for assessing the availability of Ca, Mn, and Zn. Soil pH and effective cation exchange capacity positively influenced the availability of Ca and negatively the availability of Mn and Zn. Thus, the precision of predicting nutrient availability in paper pulp amended tropical acid soils could be improved by including soil pH or effective cation exchange capacity in relevant regression equations.  相似文献   

16.
Humic and fulvic acids extracted from alkali treated municipal sludge contain more higher molecular weight materials than from secondary wastewater effluents. This suggests that higher molecular weight materials (greater than 30 000)' are more easily entrapped on the proteinaceous surface of the biomass. About 28% of the sludge COD is humic material. The humic acid fraction is of a higher molecular weight than the fulvic acid fraction. The value of theE 4:E 6 ratio indicates that humic materials of raw sludges are of recent origin.  相似文献   

17.
Tamarind (Tamarindus indica L.) is a tropical fruit tree highly valued for its fruit pulp. It has been identified as one of the priority species with great potential for domestication in the Sahelian countries of Sub-Saharan Africa. An important step in the domestication process is the characterization of the local natural variation of the species in order to select the most interesting phenotypes/genotypes which possess several desired traits for breeding purposes. Four provenances covering contrasting agro-ecological zones in Mali were selected for fruit morphological and nutritional traits (tartaric acid and sugars). Tamarind trees from the driest provenance contained smaller fruits with a smaller amount of pulp compared to provenances from wetter zones. Tamarind trees in Mali have a low real pulp value (maximum 9.5) and bear sour fruits (high tartaric acid content of 9–12 %). Some sweet-fruited trees could be identified, but the sweetness was low (maximum 8). Fruit traits seem to be influenced by climate and soil characteristics, which should be taken into account in the domestication process, when planting trees in a different region of origin. We selected a few elite trees within each provenance, containing the best combination for the most desirable fruit traits, using web diagrams. Frequency distributions of the different fruit traits showed some traits are probably the target of selection by farmers. All provenances, except the driest one, indicated a possible very first stage of domestication.  相似文献   

18.

Aim and Background  

In order to identify potential risks of sediments contaminated by pulp and paper mill effluents, two boreal lake areas were investigated from core samples. Resin acids (RA) and their aromatized derivative retene were measured, suggesting that these aquatic toxicants can be long-lasting sources to expose benthic biota. On the other hand, dredging or other human actions can liberate toxicants, even from deep sediments, to an aqueous phase with harmful consequences to aquatic species. Since no historical sediment profiles were available, we investigated the toxic potential of sediment-water elutriates by way of the bioluminescent bacteria Vibrio fischeri. In this investigation, we therefore analyzed both the concentrations of toxic chemicals and the toxicity as profiles in two contaminated lake sediments in Finland.  相似文献   

19.
This study was performed to evaluate the ability of white-rot fungi to decolorize dye effluents. A total of 222 isolates of white-rot fungi were initially investigated to assess their ability to decolorize chemically different synthetic dyes in solid medium, resulting in selection of 25 isolates including four isolates of Berkandera adusta, five isolates of Ceriporia lacerata, three isolates of Irpex lacteus, one isolate of Perenniporia fraxinea, ten isolates of Phanerochaete spp., one isolate of Phlebia radiata, and one isolate of Porostereum spadiceum. Of the 25 isolates, B. adusta KUC9065, C. lacerata KUC8090, P. calotricha KUC8003, and P. spadiceum KUC8602 were finally selected on the basis of their ability to decolorize synthetic dyes in liquid medium, and were used to decolorize industrial effluents. B. adusta KUC9065 increased the transmittance of visible light by 71–92 %. Decolorization of wastewater by B. adusta KUC9065 was probably caused by the lignin-modifying enzymes produced by the fungus. In addition, the acute toxicity to Daphnia magna decreased from 2.5 to 2.1 and from 3.5 to 2.6 toxic units over 24 and 48 h, respectively.  相似文献   

20.
Whole berries, seeds, and pulp/peel of goldenberry (Physalis peruviana L.) were compared in terms of fatty acids, lipid classes, triacylglyerols, phytosterols, fat-soluble vitamins, and beta-carotene. The total lipid contents in the whole berries, seeds, and seedless parts were 2.0, 1.8, and 0.2% (on a fresh weight basis), respectively. Linoleic acid was the dominating fatty acid followed by oleic acid as the second major fatty acid. Palmitic and stearic acids were the major saturates. In pulp/peel oil, the fatty acid profile was characterized by higher amounts of saturates, monoenes, and trienes than in whole berry and seed oils. Neutral lipids comprised >95% of total lipids in whole berry oil and seed oil, while neutral lipids separated in lower level in pulp/peel oil. Triacylglycerols were the predominant neutral lipid subclass and constituted ca. 81.6, 86.6, and 65.1% of total neutral lipids in whole berry, seed, and pulp/peel oils, respectively. Nine triacylglycerol molecular species were detected, wherein three species, C54:3, C52:2, and C54:6, were presented to the extent of approximately 91% or above. The highest level of phytosterols was estimated in pulp/peel oil that contained the highest level of unsaponifiables. In both whole berry and seed oils, campesterol and beta-sitosterol were the sterol markers, whereas Delta5-avenasterol and campesterol were the main 4-desmethylsterols in pulp/peel oil. The tocopherols level was much higher in pulp/peel oil than in whole berry and seed oils. beta- and gamma-tocopherols were the major components in whole berry and seed oils, whereas gamma- and alpha-tocopherols were the main constituents in pulp/peel oil. beta-Carotene and vitamin K(1) were also measured in markedly high levels in pulp/peel oil followed by whole berry oil and seed oil, respectively. Information provided by the present work is of importance for further chemical investigation of goldenberry oil and industrial utilization of the berries as a raw material of oils and functional foods.  相似文献   

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