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The aromatic compounds substituted with sulfonate groups, being xenobiotic, resist biodegradation in the environment and tend to accumulate up to toxic levels. The hydrophilic sulfonated group makes these compounds highly water soluble and they tend to pass through water-treatment plants. The release of untreated effluents from these industries results in pollution of water bodies affecting aquatic fauna. Thus, the toxicity regarding these compounds is of major concern. The 2-naphthalene sulfonate is a sulfonated aromatic compound being widely used in textile industries. Being non-biodegradable concern regarding its toxicity has risen. Thus in the light of above facts, the present study was undertaken to determine the toxicity of 2-naphthalene sulfonate in blood cells of Channa punctatus. For this, LD50 was determined and after selection of sublethal doses oxidative stress, genotoxicity and bioaccumulation were studied. For oxidative stress determination, biochemical markers such as malondialdehyde content and activities of superoxide dismutase, catalase, and glutathione-S-transferase were studied. Genotoxicity was studied using comet and micronucleus assay. Significant increase in oxidative stress and DNA damage in the exposed groups as compared to control group (P ≤ 0.05) was observed till 96 h. However, decreased values of all the studied parameters at 720 h (30 days) indicate repair capacity of fish. Further, the bio accumulative potential of 2-naphthalene sulfonate was assessed in blood plasma using high-performance liquid chromatography. The study revealed the toxic potential of 2-naphthalene sulfonate to aquatic organisms thus stressed on the need for the implementation of stringent policies regarding the management of such toxic compounds.

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.

Aromatic sensitizers and related compounds (SRCs) originating from thermal recording material as impurities in waste paper have been detected in aquatic environments near cities where the paper industry is flourishing. In the present study, the levels of exposure to such SRCs and the stable isotope ratios (δ13C and δ15N) in different fish species (Konosirus punctatus, Takifugu niphobles, and Tribolodon hakonensis) were analyzed. These fish species were collected from the vicinity of waste paper recycling plants in Japan. Eleven SRCs were identified in fish muscle at total concentration levels (ΣSRCs) of 64 to 818 ng/g wet weight (mean 181 ng/L wet wt). The dominant SRCs in the fish samples were 1,1-di(4-methylphenyl)ethane, 1,2-bis(3-methylphenoxy)ethane, and 1,4-dibenzyloxybenzene. Stable isotope ratios showed that, although three species feed on the same trophic level, K. punctatus and T. niphobles live in waters farther offshore than those in which T. hakonensis live. The contributions of various factors to the accumulation were also assessed. The lipid content (r2 = 0.512, p

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 question of polycyclic aromatic hydrocarbon (PAH) bioavailability and its relationship to specific PAH sources with different PAH binding characteristics is an important one, because bioavailability drives PAH accumulation in biota and ultimately the biochemical responses to the PAH contaminants. The industrial harbour at Kitimat (British Columbia, Canada) provides an ideal location to study the bioavailability and bioaccumulation of sediment hydrocarbons to low trophic level biota. Samples of soft shell clams (Mya arenaria) and intertidal sediment collected from multiple sites over six years at various distances from an aluminium smelter and a pulp and paper mill were analysed for 106 PAHs, plant diterpenes and other aromatic fraction hydrocarbons. Interpretation using PAH source ratios and multivariate data analysis reveals six principal hydrocarbon sources: PAHs in coke, pitch and emissions from anode combustion from the aluminium smelter, vascular plant terpenes and aromatised terpenes from the pulp and paper mill, petroleum PAHs from shipping and other anthropogenic activities and PAHs from natural plant detritus. Harbour sediments predominantly contain either pitch or pyrogenic PAHs from the smelter, while clams predominantly contain plant derived PAHs and diterpenes from the adjacent pulp mill. PAHs from the smelter have low bioavailability to clams (Biota-Sediment Accumulation Factors; BSAFs1 for pitch and coke;10 for anode combustion, decreasing to ∼0.1 for the mass 300 and 302 PAHs), possibly due to binding to pitch or soot carbon matrices. Decreases in PAH isomer ratios between sediments and clams likely reflect a combination of variation in uptake kinetics of petroleum PAHs and compound specific metabolism, with the importance of petroleum PAHs decreasing with increasing molecular weight. Plant derived compounds exhibit little natural bioaccumulation at reference sites, but unsaturated and aromatised diterpenes released from resins by industrial pulping processes are readily accumulated by the clams (BSAFs500). Thus while most of the smelter associated PAHs in sediments may not be bioavailable to benthic organisms, the plant terpenes (including retene, totarol, ferruginol, manool, dehydroabietane and other plant terpenes that form the chemical defence mechanism of conifers) released by pulp mills are bioavailable and possess demonstrated toxic properties. The large scale release of plant terpenes by some of the many pulp mills located in British Columbia and elsewhere represents a largely undocumented risk to aquatic biota.

The accumulation of ligands for the aryl hydrocarbon receptor (AhR) and fish sex steroid receptors was investigated using two separate controlled fish exposures to final effluent from a bleached sulfite/groundwood mill in New Brunswick, Canada. In the first experiment, hepatic tissue extracts from exposed fish were fractionated according to lipophilicity. Fractions with different octanol-water (Kow) partition coefficients were tested for the presence of bioavailable chemicals that function as ligands for the AhR in H4IIE cells, rainbow trout hepatic estrogen receptors (ER), goldfish testicular androgen receptors (AR), and goldfish sex steroid binding protein (SSBP). Fish accumulated ligands for each receptor after 4-d exposure to effluent. Single fractions contained ligands for the AhR and the ER, while multiple fractions competed for the AR and SSBP. Fish also accumulated ligands for the AhR and SSBP from Saint John River dilution water, indicating upstream sources of bioactive substances. Semipermeable-membrane devices deployed concurrently with fish accumulated ligands from effluent for all receptors except the ER. In the second experiment, accumulated ligands were evaluated after exposure of fish to effluent for two different durations and following a depuration period. Hepatic mixed function oxygenase activity and whole-liver hormonal activity, measured as binding to SSBP, returned to background following 6 d depuration and were reduced but still significant after 12-d exposure to effluent. Whole-liver extract affinities for the AR were maintained after extended exposure and depuration, indicating the potential for AR ligands to bioaccumulate. The accumulation of AhR ligands and ligands for sex steroid receptors provides a mechanistic linkage to effects on growth, development, and performance of fish exposed to effluent from this and other mills.

Since 1988, the State of Maine has monitored dioxin levels in the tissues of predatory and bottom feeding species of fish taken from the state′s major water bodies, including five rivers which receive the effluent of bleached kraft paper mills. Data are also available on dioxin concentrations in the effluent of these mills. Monitoring results were analyzed using simple models to yield field bioaccumulation factors (BAFs) for 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD) in Maine rivers. Three BAFs were computed for each fish species at each site to account for declining TCDD levels in mill effluents over time. Mean BAFs (across rivers) ranged from 11,500 to 24,600 for smallmouth bass fillets, from 17,900 to 28,300 for brown trout fillets, from 3000 to 7500 for white perch fillets, and from 78,500 to 106,000 for white sucker whole bodies. Field BAFs obtained in this analysis are similar to factors obtained in recent laboratory studies of TCDD accumulation in fish. Our results suggest that EPA′s currently recommended BCF value of 5000 is probably too low. Instead, a value between 15,000 and 25,000 is considered a reasonable estimate of the BAF to use for regulatory purposes in the state of Maine.

The interest in the use of recycled products has been growing for the past many years. Thus, the dangerous chemicals once in use, now forbidden, may persist in the recycled products. This may pose a problem of bioaccumulation of poisonous chemicals as well as a threat to the philosophy of the use of recycled products. The non-carbon copying paper containing 2-6% polychlorinated biphenyls (PCB's) by weight has been commonly used in the nineteen sixties. Although the use of non-carbon copypaper has been forbidden for the past 15 years, it has been demonstrated that recycled papers contained small amounts of PCB's similar to those used for the production of non-carbon copypaper. Thus the old discarded archives may be one of the sources of PCB's in the recycled papers. Besides PCB's cadmium (Cd), mercury (Hg), lead (Pb) and other heavy metals from the print-inks (colors) may also be introduced to the recycled paper. The aim of the present study was to evaluate, on behalf of Danish Environmental Protection Agency, the levels of PCB's, Cd, Hg and Pb in the recycled paper for the household use. For this purpose the authors undertook a pilot study for the determination of the contents of PCB'smore » Cd, Hg and Pb in recycled papers that were available in the Danish market.« less