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Ethnopharmacobotanical information reports that Parkinsonia aculeata infusion is used to control diabetes-related complications and dyslipidemia. However, few studies are reported on the safe use of this species. The aim of this study is to evaluate the acute toxicity, embryotoxicity and cytotoxicity of a polar fraction obtained from hydroethanolic extract of P. aculeata (PfrHEPA). For the acute toxicity test, we considered the Up and Down method which the guidelines are described by the Organization for Economic Cooperation and Development (OECD N°425). The animals were treated with PfrHEPA (2000 mg/kg) or with distilled water (10 ml/kg) by gavage and observed from Day 1 to14. For embryotoxicity assay, zebrafish embryos were exposed to PfrHEPA (100 mg/L) and toxicity parameters were observed during four consecutive days. The cytotoxicity of PfrHEPA (5, 10, 25, 50, 75 and 100 μg/ml, respectively) was performed on normal cell lines (mesenchymal stem cells, African green monkey renal cells and mouse pre-adipocytes 3 T3-L1 using the MTT salt reduction assay. In the acute toxicity test, no mortality was observed in mice treated with PfrHEPA (2000 mg/kg), as well as behavioral changes, histopathological abnormalities and hematological and biochemical variables. In the embryotoxicity test, no abnormal changes related to the toxicological parameters were observed in the period of 96 h. Regarding the cytotoxicity assay, PfrHEPA showed no cytotoxic effect on the normal cell lines tested, with an IC50 value > 100 μg/ml. These results suggest the safe use of P. aculeata, however, more trials are needed for PfrHEPA to be presented as new safe therapeutic proposal for the control of metabolic disorders.

In this study, an internal circulation-anoxic/aerobic (IC-A/O) process followed by ultrafiltration (UF) and reverse osmosis (RO) system was applied for paper wastewater reclamation. The IC-AO system presented a stable and efficient performance, achieving high removal of chemical oxygen demand (COD), total organic carbon (TOC) and total nitrogen (TN) with methane production rate of 132.8 mL/d. Acute toxicity to Daphnia magna (D. magna) was reduced significantly (83.2%) and the spearman's rank correlation analysis indicated that the toxicity of effluents from each reactor were positively correlated with COD and TOC. Hexadecanoic acid, octadecanoic acid and benzophenone were the main toxic contributors for biological effluent. Microbial community revealed that Anaerolinea was significantly related with organic pollutants. The UF-RO system further removed pollutants and toxicity with the final effluent COD, TOC, ammonium nitrogen (NH4+-N) and TN of 32.6, 18.8, 0.3 and 9.2 mg/L, respectively, which proved that it was feasible for paper wastewater reuse. This study presented an efficient, practical and environmentally competitive system, and paved a foundation for the treatment and reuse of paper wastewater.

Qing Hao Gan Cao (QHGC), a Chinese medicinal formula containing Artemisia annua and Glycyrrhizae Radix et Rhizoma, has been used to treat sunstroke and as an antiviral agent for more than 800 years. It has not previously been subject to a toxicological safety evaluation in acute and subacute (28 days) studies. Therefore, the acute and subacute toxicity of an aqueous extract of QHGC were evaluated in vivo. For the QHGC preparation, the botanical raw materials were crushed into pieces and mixed in the ratio of 10:1 in distilled water for 12 h, then boiling three times for 2 h each time. The three decoctions were mixed and filtered, then spray-dried with hot air at 160°C for 30 min, and stored at room temperature. For the acute toxicity test, 72.0 g/kg of QHGC extract was administered by gavage to male and female mice. Body weight, general observations, and autopsy results were recorded. No mortality or toxicity signs were observed during the studies. For the subacute toxicity test, 4.0, 8.0, or 16.0 g/kg/day of QHGC extract was administered to rats for 28 days. General observations and mortality, body weight, biochemical and hematological parameters, organ weight, and pathological morphology were analyzed. The acute and subacute toxicity studies did not show significant changes in body weight, general observations, hematology and biochemical parameters, organ weight, and liver, spleen, stomach, duodenum, testis, ovary, lung, heart, and kidney histopathological analyses. The consumption of QHGC aqueous extract can be considered safe within the conditions of this study.

B-FOS (butyl-fructooligosaccharide) is a newly synthesized prebiotic molecule, formed by the combination of FOS and butyrate by ester bonds. B-FOS has been reported to have the potential prebiotic effect of promoting intestinal flora diversity and enhancing butyrate production. The aim of this study was to investigate the potential acute and sub-chronic toxicity of B-FOS in Institute of Cancer Research (ICR) mice and Wistar rats to verify its biosafety. ICR mice were administered a single oral gavage of B-FOS at doses of 0, 500, 1000, and 2000 mg/kg body weight and observed for signs of acute toxicity for 14 days. Sub-chronic toxicity was evaluated by repeated oral administration of B-FOS at 2000 mg/kg for 28 days, in accordance with Organization for Economic Co-operation and Development (OECD) protocol test numbers 420 and 407. No mortality or abnormal clinical signs were observed during the experimental periods after B-FOS administration. Furthermore, no significant changes in body weight, organ weight, serum biochemical parameters, or tissue histology were observed after animal sacrifice. These in vivo results indicate that B-FOS does not exert any acute or sub-chronic toxicity at a dose of 2000 mg/kg, and this novel molecule can be regarded as a safe prebiotic substance for use in the food and nutraceutical industries.

Eucalyptus bleached kraft pulp production, an important sector of the Brazilian national economy, is responsible for generating large volume, high pollutant load effluents, containing a considerable fraction of recalcitrant organic matter. The objectives of this study were to quantify the biological activity of the effluent from a eucalyptus bleached kraft pulp mill, characterize the nature of compounds responsible for biological activity and assess the effect of ozone treatment on its removal. Primary and secondary effluents were collected bimonthly over the course of one year at a Brazilian bleached eucalypt kraft pulp mill and their pollutant loads (biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic carbon (TOC), adsorbable organic halogen (AOX), lignin, extractives) and biological activity (acute and chronic toxicity and estrogenic activity) quantified. The effluent studied did not present acute toxicity to Daphnia, but presented the chronic toxicity effects of algal growth inhibition and reduced survival and reproduction in Ceriodaphnia, as well as estrogenic activity. Chronic toxicity and estrogenic activity were reduced but not eliminated during activated sludge biological treatment. The toxicity identification evaluation revealed that lipophilic organic compounds (such as residual lignin, extractives and their byproducts) were responsible for the toxicity and estrogenic activity. Ozone treatment (50 mg/L O3) of the secondary effluent eliminated the chronic toxicity and significantly reduced estrogen activity.

Toxicity of dye containing effluent of tannery, textile, dyes and pulp-paper industries was evaluated in an acute toxicity test using Daphnia magna. The 48-hour EC50 values were 4.33% and 19.5% for tannery effluents (Tn1 and Tn2). Textile effluents (Tx1—Tx7) had 48-hour EC50 values; >100%, >100%, 62.9%, 63.0%, 40.3%, >100% and >100%, respectively. Dye industries (D1—D7) had 48-hour EC50 values; 14.1%, 15.5%, 24.5%, 29.7%, 23.2%, >100% and >100%, respectively. Similarly pulp-paper effluents (P1—P5) showed acute toxicity as 100%, 77.87%, 46.44%, 69.55% and 82.84%, respectively. These results showed linear relationship with high degree of confidence (r2 ≥ 0.84—0.99) between immobility and test concentrations. Toxicity classification criteria showed that out of five effluents from pulp-paper mill, four were minor acutely toxic having 48-hour EC50 value in between >46%—100%. Out of seven textile effluents, four were not acutely toxic (48-hour EC50 value >100%) and three were minor acutely toxic (48-hour EC 50 value in the range of 40.3%—63.0%). Similarly, out of seven dye industrial effluents, two were not acutely toxic and five minor acutely toxic. One of the two tanneries was moderately acutely toxic and another one was minor acutely toxic. Classification based on toxic unit revealed that four out of five pulp-paper effluent, three out of seven textile effluents, five out of seven dye effluents and both the tannery effluents were toxic. Overall, 66.67% effluents were found toxic and 33.33% as non-toxic. In general, tannery and dyes effluents showed more toxicity than textile and paper mill effluents.

The combined biological and chemical treatments of the cellulose effluents have been studied aiming to promote a more significant degradation of their recalcitrant compounds and to reduce their toxicity, as compared with the isolated treatments. In this work the effluent from acid stages of the ECF bleaching of Eucalyptus urograndis pulp was treated by using separately activated sludge and UV radiation and its combination. The treatment efficiency was evaluated by colour, total phenol, COD, BOD, UV spectroscopy, molar weight distribution and toxicity. The untreated effluent presented 587 ± 18 CU, 19.3 ± 0.6 mg.L −1 of total phenol, 2,246 ± 137 mgO 2 .L −1 of COD and 904 ± 48 mgO 2 .L −1 of BOD. It did not show acute toxicity to Escherichia coli , but presented chronic toxicity to Selenastrum capricornutum (EC 50 = 25%). The sludge treatment resulted in a colour increasing of 42% and decreasing of total phenol, COD and BOD of 33%, 64% and 92%, respectively. The UV radiation treatment for 120 min resulted in a decrease of colour, total phenol, BOD and COD of 70%, 43%, 62% and 43%, respectively. The combined treatment promoted an expressive decrease for colour and total phenol. The UV absorption indicated a degradation of the aromatic compounds. The biological treatment did not remove chronic toxicity and after UV radiation treatment, a 10 times improving toxicity was noticed.

The aim of this study was to investigate the acute toxicity of pulp-paper industry wastewater using traditional and enrichment toxicity tests and to emphasize the importance of toxicity tests in wastewater discharge regulations. Enrichment toxicity tests are novel applications and give an idea of whether there is potential toxicity or growth-limiting and -stimulating conditions. Different organisms were used such as bacteria (floc and coliform bacteria), algae (Chlorella sp.), protozoa (Vorticella sp.), and fish (Lepistes sp.) to represent four trophic levels. Furthermore, chemical oxygen demand (COD) fractionation results were compared with these tests to assess the effect of COD subcategories on the determination of possible toxicity. The pulp-paper industry results revealed acute toxicity to at least two organisms in 6 of 20 effluent samples. The toxicity test results were assessed with chemical analyses such as COD, biochemical oxygen demand (BOD), color, absorbable organic halogen (AOXs), and phenol. It was observed that the toxicity of the effluents could not be explained by using physicochemical analyses in four cases for the pulp-paper industry. The results clearly indicate that bioassay tests provide additional information on the toxicity potential of industrial discharges and effluents. (C) 2002 Elsevier Science (USA). All rights reserved.

The acute toxicity of fatty acids (C14 to C18) commonly found in wood was determined by the standard algal growth inhibition test using the freshwater green alga Selenastrum capricornutum. Toxicity, quantified as IC50 values, varied depending on the number of total carbons and double bonds. Of the tested acids, oleic (cis-9-octadecenoic) acid showed the highest toxicity (72-h IC50 = 0.47 mg/L) to the alga, and triolein, a triglyceride of oleic acid, showed no apparent toxicity. Further examination of a series of C18:1 acids with a double bond at the 6, 11, or 12 position revealed that both double-bond position and cis or trans configuration affected toxicity. The 72-h IC50 data for these fatty acids and related compounds seemed to correlate well with the melting point (mp), showing two separate linear relationships: at mp35 degrees C toxicity increased with increasing melting point, and at mp40 degrees C toxicity decreased with melting point.

The applicability of the Whole Effluent Assessment concept for the proof of compliance with the “best available techniques” has been analysed with paper mill wastewater from Germany by considering its persistency (P), potentially bio-accumulative substances (B) and toxicity (T). Twenty wastewater samples from 13 paper mills using different types of cellulose fibres as raw materials have been tested in DIN or ISO standardised bioassays: the algae, daphnia, luminescent bacteria, duckweed (Lemna), fish-egg and umu tests with lowest ineffective dilution (LID) as test result. The potentially bio-accumulative substances (PBS) were determined by solid-phase microextraction and referred to the reference compound 2,3-dimethylnaphthalene. Usually, a primary chemical–physical treatment of the wastewater was followed by a single or multi-stage biological treatment. One indirectly discharged wastewater sample was pre-treated biologically in the Zahn–Wellens test before determining its ecotoxicity. No toxicity or genotoxicity at all was detected in the acute daphnia and fish egg as well as the umu assay. In the luminescent bacteria test, moderate toxicity (up to LIDlb = 6) was observed. Wastewater of four paper mills demonstrated elevated or high algae toxicity (up to LIDA = 128), which was in line with the results of the Lemna test, which mostly was less sensitive than the algae test (up to LIDDW = 8). One indirectly discharged wastewater sample was biodegraded in the Zahn–Wellens test by 96% and was not toxic after this treatment. Low levels of PBS have been detected (median 3.27 mmol L−1). The colouration of the wastewater samples in the visible band did not correlate with algae toxicity and thus is not considered as its primary origin. Further analysis with a partial wastewater stream from thermomechanically produced groundwood pulp (TMP) revealed no algae or luminescent bacteria toxicity after pre-treatment of the sample in the Zahn–Wellens test (chemical oxygen demand elimination 85% in 7 days). Thus, the algae toxicity of the respective paper mill cannot be explained with the TMP partial stream; presumably other raw materials such as biocides might be the source of algae toxicity. Comparative data from wastewater surveillance of authorities confirmed the range of ecotoxicity observed in the study. Wastewater from paper mills generally has no or a moderate ecotoxicity (median LID 1 and 2) while the maximum LID values, especially for the algae and daphnia tests, are considerably elevated (LIDA up to 128, LIDD up to 48). Wastewater from paper mills generally is low to moderately ecotoxic to aquatic organisms in acute toxicity tests. Some samples show effects in the chronic algae growth inhibition test which cannot be explained exclusively with colouration of the samples. The origin of elevated algae ecotoxicity could not be determined. In the algae test, often flat dose–response relationships and growth promotion at higher dilution factors have been observed, indicating that several effects are overlapping. At least one bioassay should be included in routine wastewater control of paper mills because the paper manufacturing industry is among the most water consuming. Although the algae test was the most sensitive test, it might not be the most appropriate test because of the complex relationship of colouration and inhibition and the smooth dose–effect relationship or even promotion of algae growth often observed. The Lemna test would be a suitable method which also detects inhibitors of photosynthesis and is not disturbed by wastewater colouration.

Spirotox is a short-term acute toxicity test with a large ciliated protozoan Spirostomum ambiguum. The test was created in the Department of Environmental Health Sciences, Medical University of Warsaw, Poland, during the early 1990s. It was presented for the first time during the 6th International Symposium on Toxicity Assessment, in Berlin in 1993. S. ambiguum was very resistant to a wide range of environmental conditions, especially to pH and dissolved oxygen. Over the last 10 years the sensitivity of S. ambiguum to many classes of toxicants was evaluated. Spirotox was found to be very sensitive to heavy metals, fungicides, and pharmaceuticals used to cure diseases of the human nervous system. On the other hand, it was generally less sensitive than standard bioassays to simple organics. Spirotox was also used for analysis of cyanobacterial blooms. Though it was moderately sensitive to hepatotoxins, the test seems to be a good tool for evaluation of the entire toxicity of blooms. The last but not the least of the applications of the Spirotox test was evaluation of the toxicity of extracts from medical devices. Protozoa, which are the simplest eukaryotes, seem to be good screening bioassays for monitoring the technology of medical device production.

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.

In order to reduce the ecotoxicity of paper mill, four different enzymatic pretreatment strategies were investigated in comparison to conventional chemical based processes. In strategy I, xylanase-aided pretreatment of pulp was carried out, and in strategy II, xylanase and laccase-mediator systems were used sequentially. Moreover, to compare the efficiency of Bacillus stearothermophilus xylanase and Ceriporiopsis subvermispora laccase in the reduction of ecotoxicity and pollution, parallel strategies (III and IV) were implemented using commercial enzymes. Conventional C(D)E(OP)D(1)D(2) (C(D), Cl(2) with ClO2; EOP, H2O2 extraction; D1 and D2, ClO2) and X/XLC(D)E(OP)D(1)D(2) (X, xylanase; L, laccase) sequences were employed with non-enzymatic and enzymatic strategies, respectively. Acute toxicity was determined by the extent of inhibition of bioluminescence of Vibrio fischeri with different dilutions of the effluent. Two-fold increase was observed in EC50 values for strategy I compared to the control process. On the other hand, sequential application of commercial enzymes resulted in higher acute toxicity compared to lab enzymes. In comparison to the control process, strategy II was the most efficient and successfully reduced 60.1 and 25.8% of biological oxygen demand (BOD) and color of effluents, respectively. We report for the first time the comparative analysis of the ecotoxicity of industrial effluents.

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 μg 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.

To determine whether a 7- to 10-d embryo toxicity/teratogenicity test with the inland silverside fish, Menidia beryllina, is a sensitive indicator for evaluation of bleached kraft mill effluents, we compared this test with the Microtox(R) 15-min acute toxicity test and the Ceriodaphnia dubia 7-d chronic toxicity test. Water samples used in each test were collected from three areas in a bleached kraft pulp and paper mill using a 100% chlorine dioxide bleaching process: 1) river water prior to use in the mill; 2) the combined acid/base waste stream from the pulping process prior to biological treatment in the aerated stabilization basin (ASB); and 3) the effluent from the ASB with a retention time of approximately 11 d. Relative toxicity determined by the three tests for each water sampling location was compared. All three toxicity tests were predictive indicators of toxicity; however, the C. dubia and M. beryllina tests were the more similar and sensitive indicators of toxicity. Process water (ASB influent) prior to biological treatment in the ASB was toxic at all concentrations using the Microtox(R) and C. dubia tests. The fish embryo test showed no toxicity at 1% concentrations, slight toxicity at 10%, and acute toxicity at the 100% ASB influent concentration. Tests with biologically-treated ASB effluent indicated a substantial reduction in observed toxicity to Microtox(R) bacteria, C. dubia, and M. beryllina. No toxic responses were observed in any test at a 1% ASB effluent concentration which was the approximate effluent concentration in the receiving river following mixing. No relationship was found among any toxicological response and effluent levels of adsorbable organic halides, polychlorinated phenolic compounds, 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, total suspended solids, color, chemical oxygen demand, or total organic carbon.

The acute toxicity to rainbow trout of untreated ammonia-base neutral sulfite pulp mill waste liquor was demonstrated in these experimants. A mean LC50 of 0.82% and 95% confidence interval of 0.08 - 1.56% was obtained in four static bioassays. Lignin, sulfur dioxide, and ammonia were implicated as toxic components. The latter two were probably the most toxic.