Evaluation of mutagenicity associated with Escherichia coli inactivation in UV-treated orange juice

UV radiation is an alternative technology for the elimination of pathogenic micro-organisms in liquid food. The objectives of this work were to investigate mutagenesis using the Ames test in : (1) fresh squeezed orange juice submitted to UV radiation doses required to achieve 5 and 10 log₁₀ reductions of different strains of Escherichia coli serotype O157:H7 at two temperatures, and (2) commercial pasteurized orange juice submitted to thermal treatment.

Two histidine-auxotrophic strains, Salmonella Typhimurium TA98 and TA97a, were used in the Ames test with and without metabolic activation.

In commercial pasteurized orange juices, mutagenesis was not observed with S. Typhimurium TA98 strain with and without metabolic activation, but high mutagenic effect was observed using TA97a with metabolic activation.

UV radiation did not affect the stability of ascorbic acid in aqueous solution. However, degradation of ascorbic acid was observed when UV treatment was performed on squeezed orange juice, following first order kinetics.

UV treatment required to achieve 5 log₁₀ reductions (1.5 J/cm²) did not show a mutagenic effect with and without metabolic activation using the tested strains, but a higher UV radiation dose necessary to produce 10 log₁₀ reductions (3.0 J/cm²) showed mutagenicity with metabolic activation.     

Biomass and carbon budgeting of sustainable agroforestry systems as ecosystem service in Indian Himalayas

Adoption of agroforestry is paramount as a climate change mitigation and adaptation strategy. The assessment of plant biomass is crucial for understanding the vulnerability of biological systems to climate change. In the present study, agroforestry systems viz., agrisilviculture (AS), agrihorticulture (AH), agrihortisilviculture (AHS) and agrisilvihorticulture (ASH) were investigated for biomass production and carbon stock in vegetation as well as in soil in the Indian central Himalaya along the elevation i.e. E₁ (<1100 m), E₂ (1100–1400 m), E₃ (1400–1700 m), E₄ (1700–2000 m) and E₅ (>2000 m). Mean aboveground and belowground biomass were 73.9% and 26.1%, respectively, of total biomass (64.4 t ha^?1) in agroforestry systems. Fodder and/or timber trees accounted for 31% (in AHS) to 74% (in AS) of total biomass, while fruit trees accounted for 18% (in ASH) to 73% (in AH) of total biomass. The contribution of agriculture crops to total biomass fluctuated between 19% (in ASH) and 26% (in AH). Total vegetation biomass, soil carbon and total carbon density in agroforestry systems increased significantly along the elevation, with maximum biomass at elevation E₅ (32.0 t ha^?1, 64.7 t C ha^?1 and 96.7 t C ha^?1). Total biomass of vegetation among agroforestry systems differed significantly. Soil carbon stock was highest in AHS (59.5 t C ha^?1) and total carbon density (vegetation + soil) was highest in ASH (93.0 t C ha^?1). Thus, in Indian Himalayas, vegetation biomass, carbon stock, soil and total carbon (vegetation + soil) stock increased along the elevation.

Abbrviations: AG: aboveground; BG: belowground; WD: wood density; VOB: volume over bark; BEF: biomass expansion factor; AS: agrisilviculture; AH: agrihorticulture; ASH: agrisilvihorticulture; AHS: agrihortisilviculture; E: elevation; C: carbon; CO₂: carbon-di-oxide; IPCC: Intergovernmental Panel on Climate Change; DBH: diameter at breast height; AGBD: aboveground biomass density; BGBD: belowground biomass density; GSVD: growing stock volume density     

DNA damage in workers exposed to formaldehyde at concentrations below occupational exposure limits

Formaldehyde has been classified in group 1 as a potential source of human carcinogen by the International Agency for Research on Cancer. In this study, we evaluated the DNA damage in workers who were occupationally exposed to formaldehyde during the manufacture of melamine dinnerware.

Age, sex, smoking habits, and socioeconomic status were matched by the controls (n = 34) of workers not occupationally exposed to formaldehyde. The median value of formaldehyde time weighted average exposure in three workshops was 0.086 mg/m³. No significant difference was observed between sex and smoking habit in the assessed workers. Alkaline comet assay of peripheral blood lymphocytes was used to determine the DNA damage in the subjects. Olive moment was significantly higher in the exposed group compared with the control group.

Overall, the results suggest that respiratory exposure to low concentrations of formaldehyde causes DNA damage in peripheral blood lymphocyte. Therefore, exposure to formaldehyde should be reduced to the lowest possible level.     

From the attitude-behaviour-gap to a producer-people-gap?

The so-called attitude-behaviour-gap of ecology might have changed to a ?producer-people-gap”. In summer 2017 in Germany, the intention of private house-builders to buy an exterior insulation system based on renewable materials was measured as positive, with a mean of 5.2 on a 1–7 Likert scale. But the intentions of professionals were clearly below, e.g. craftsmen, with an average of 3.6 on the same scale – although both groups, the privates and the professionals, judged that there is a clear trend towards such products.

Because of these findings, an additional investigation of management by producers was conducted in autumn and winter 2017/2018, in which a very critical atmosphere towards renewable materials was found. It was analyzed that the managements` attitudes might not be a basic refusal of renewable material in general, but rather a fear of costs of research and development of new products.

A concept was tested, to see if it would be possible to cause an attitude change within the professional key target groups just by applying marketing instruments. Five articles in key media of this market have been published between February and May 2018. In the following evaluation (n = 150) in May 2018 significant effects of the communication have been measured: The intention of decision-makers in craftsmen`s businesses to buy an exterior insulation system based on renewable material rose significantly (0.01 Lv.) from a mean of 3.6 in 2017 to 4.4 in 2018.     

Effective removal of Cobalt(II) ions from aqueous solutions and nuclear industry wastewater using sulfhydryl and carboxyl functionalised magnetite nanocellulose composite: batch adsorption studies

A new adsorbent sulfhydryl and carboxyl functionalized magnetite nanocellulose composite [(MB-IA)-g-MNCC] was synthesized by graft co-polymerization of itaconic acid onto magnetite nanocellulose (MNCC) using EGDMA as cross linking agent and K₂S₂O₈ as free radical initiator. The adsorption occurs maximum in the pH 6.5. The best fitted kinetic model was found to be pseudo-second-order kinetics. Therefore the mechanism of Co(II) adsorption onto (MB-IA)-g-MNCC follows ion exchange followed by complexation. The Langmuir model was the best fitted isotherm model for the adsorption of Co(II) onto the (MB-IA)-g-MNCC. Simulated nuclear power plant coolant water samples were also treated with (MB-IA)-g-MNCC to demonstrate its efficiency for the removal of Co(II) from aqueous solutions in the presence of other metal ions. To recover the adsorbed Co(II) ions and also to regenerate the adsorbent to its original state 0.1?M HCl was used as suitable desorbing agent. Six cycles of adsorption-desorption experiments were conducted and was found that adsorption capacity of (MB-IA)-g-MNCC has been decreased from 97.5% in the first cycle to 84.7% in the sixth cycle. Recovery of Co(II) using 0.1?M HCl decreased from 93.2% in the first cycle to 79.3% in the sixth cycle.

Abbreviations: T: absolute temperature; q_e: amount adsorbed at equilibrium; q_t: amount adsorbed at time t; CELL: cellulose; Co: cobalt; C_e: concentration at equilibrium; C_HCl: concentration of HCl; C_NaOH: concentration of NaOH; C_A: concentrations of acid; C_B: concentrations of base; W_g: dry weight of composite; W_i: dry weight of MNCC; DS: energy dispersive spectra; EGDMA: ethylene glycol dimethacrylate; Ce: equilibrium concentration; K_L: equilibrium constant; F: Faradays constant; FTIR: Fourier transform infrared spectra; ΔG^o: free energy change; K_F: Freundlich adsorption capacity; 1/n: Freundlich constant; R: gas constant; D: grafting density; EC_o: initial concentration; IA: itaconic acid; IA-g-MNCC: itaconic acid-grafted-magnetite nanocellulose composite; b: Langmuir constant; MNCC: magnetite nanocellulose composite; Q⁰: Maximum adsorption capacity; (MB-IA)-g-MNCC: 2-mercaptobenzamide modified itaconic acid-grafted-magnetite nanocellulose composite; NC: nanocellulose; pH_pzc: Point of zero charge; K₂S₂O₈: potassium peroxy sulphate; k₁: pseudo-first-order rate constant; k₂: pseudo-second-order rate constant; SEM: scanning Electron Microscope; b_s: Sips adsorption capacity; Q_s: Sips maximum adsorption capacity; ΔH°: standard enthalpy change; ΔS°: standard entropy change; A: surface area; σ₀: surface charge density; 1/n_s: surface heterogeneity factor; VSM: vibrating sample magnetometer; V: volume of solution; W: weight of (MB-IA)-g-MNCC; M_composite: weight of the composite; XRD: X-ray diffraction     

Peregrine falcon egg pollutants

The role of the peregrine falcon (Falco peregrinus) as a bioindicator for the accumulation of organohalogen compounds and other persistent organic pollutants has been established in field studies. Biometric indices for damage caused by pollutants such as the shell thickness and the shell index were determined and the egg contents were analyzed for various pollutants by gas chromatography/mass spectrometry. A wide range of chemically activated luciferase expression (CALUX®) bioassays were performed on subsamples of the eggs.

The following organohalogen compounds were found in the eggs of 2009: dichlorodiphenyltrichloroethane (DDT) and dichlorodiphenyldichloroethane, heptachlor epoxide, hexachlorobenzene, dieldrin, hexachlorocyclohexane, polychlorobiphenyls and polychlorodibenzodioxins and polychlorodibenzofurans, polybromodiphenyl ethers, hexabromocyclododecane, tetrabromobisphenyl A, perfluoro compounds, and mercury. The DDT metabolite, dichlorodiphenyldichloroethene (DDE) (11,800 ng/g dry matter), was found to be the most highly concentrated egg contaminant followed by 2,2′,4,4′,5,5′-hexachlorobiphenyl (3800 ng/g). After a past general drop in pollution level, most egg contaminants presently plateau at levels that may still exceed limit values in foods of animal origin (DDE) or even toxicological thresholds (polychlorobiphenyls + polychlorodibenzodioxins, polybromodiphenyl ethers, perfluorooctanesulfonate, methylmercury).

Accumulation of DDE could be shown in peregrine falcon eggs from the uplands of Southwest Germany with elevations up to 1500 m, presumably due to its global distribution and its cold condensation in higher altitudes. In contrast, the concentration of polychlorobiphenyls in falcon eggs decreases with elevation, indicating that these pollutants originate mainly from conurbations and local industrial sites.

Significant negative correlations were found between both shell index and thickness and the concentration of Hg. A deleterious effect is also evident from a no-observed-adverse-effect level of 120 ng MeHg per gram egg determined by other authors in chronic feeding studies with ibises, which resulted in decreased egg productivity and male homosexual nesting and courtship behavior. The average Hg concentration in the peregrine falcon eggs from 2009 is almost four times higher than this level. MeHg accounted for 82.5% of the Hg present in the eggs of 2009 and 2010.

The cell test DR CALUX® for screening of dioxin-like activities can be used to detect not only the 29 regulated dioxin-like substances but also many other persistent organic pollutants with dioxin-like potencies, such as mixed halogenated dioxins/biphenyls. In our case, the results of bioanalytical screening methods showed no additional effect of other compounds with dioxin-like activity.

Ninety-three out of 177 analytes sought could be detected in the eggs. Chlorinated paraffins, organotin compounds, some pesticides that are still in use, and phthalic esters with the exception of traces of diethylhexyl phthalate could be excluded. All pollutants found in the eggs belong to substance classes banned by the Stockholm and Minamata Conventions.     

Mountain environment and population in Georgia: case study of Upper Svaneti

The purpose of the presented research is to identify local community opinions toward ecological problems in one of the mountainous region of Georgia (Upper Svaneti), to analyze how population ‘perceive, experience, and interpret’ the social, and ecological issues.

The paper is based on the results of Upper Svanet ipopulation’s survey which was carried out by the authors of presented paper during the August of 2015 and 2016.The questionnaire was elaborated taking into account the peculiarities of the region. Stratified-cluster selection method was used for selection of respondents and database compilation. For statistical analysis of polling data the SPSS package was used.

Based on the statistical analysis of survey results, the following issues have been studied: the most important ecological problems, environmental problems with respect to socio-economic ones, information sources on ecological problems, people’s trust in environmental issues, awareness level of the population on environmental policy, their personal contribution in environmental protection, ways to solve ecological problems, implemented environmental measures.

The obtained results are important to foster mountain population’s active participation in processes that contribute to decision-making processes, planning and implementing programs for sustainable development.     

Impacts of urbanization: diversity and the symbiotic relationships of rural,urban, and spaces in-between

This Impacts article proposes strategies for mitigating negative impacts of urbanization in rural locations in the United States. Issues addressed include impacts of population growth and development, loss of agricultural lands, and impacts of climate change on agriculture and rural communities. Conclusions are supported by stakeholder survey data, geographic information systems-based data, and desktop reviews of research journal publications. We propose a sustainable, diversified approach that supports mitigation of issues, including increasing demand on food production and decline of rural communities. A key issue that we address is where we will find suitable landscapes to reduce enough food for 9.6 billion people living in 2050.

Urban and rural development planners are grappling with solutions to escalating impacts global populations, stresses on food production, and effects of climate change. Solutions are identified, including strengthening rural and urban contexts by establishing connected and interdependent links that support diversification of rural and urban contexts as viable solutions to these issues.

Diversified rural-to-urban sustainable agriculture production is a promising approach to addressing climate change impacts. Organic agriculture principles exhibit strong diversity and are accredited by United States Department of Agriculture as the only federally certified sustainable agriculture practice in the United States. Sustainable agriculture practices are evolving into profitable diversified alternative food sources. We offer substantiated alternative solutions for remediating impacts of urbanization on rural agriculture and communities. Collectively, these solutions can strengthen symbiotic relationships between sustainable agriculture and rural communities, addressing our growing population issues and preserving our dwindling farmlands and rural communities.     

南方某铀矿山废水对生物的急性毒性研究

为探明铀矿山对周围环境的联合毒性机制,本研究以常用生物毒性测试菌种——发光细菌青海弧菌Q67和费氏弧菌以及禾花鲤为受试生物代表,实地采集的铀矿山废水为目标废水,研究铀矿山废水对发光细菌和禾花鲤的急性毒性。实验结果表明,矿山废水对3种生物的急性毒性存在显著的剂量-效应关系,毒性效应浓度EC_(50)(LC50)的大小顺序为禾花鲤幼鱼费氏弧菌青海弧菌Q67,Pb~(2+)/U~(6+)浓度分别为6.052/3.026 mg·L~(-1)、2.284/1.142 mg·L~(-1)、1.339/0.669 mg·L~(-1),均可有效指示矿山废水的毒性水平,其中发光细菌更为灵敏、快速;且青海弧菌Q67的EC_(50)值最小,灵敏度最高,可作为表征矿山废水毒性风险的首选指示物。研究结果能够为放射性矿区废水生态风险预警、安全处理处置、水质基准制定及流域水环境管理提供依据。     

Evaluation of tests to assess the quality of mine-contaminated soils

An acid metal-contaminated soil from the Aljustrel mining area (a pyrite mine located in SW Portugal in the Iberian Pyrite Belt) was subjected to chemical characterisation and total metal quantification (Cd, Cr, Cu, Ni, Pb and Zn). Water-soluble metals were determined and a sequential extraction procedure was used to investigate metal speciation. Two bioavailable metal fractions were determined: a mobile fraction and a mobilisable fraction. Soil ecotoxicity was studied using a battery of bioassays: plant growth test and seed germination with cress (Lepidium sativum L.), earthworm (Eisenia fetida) mortality, E. fetida avoidance behaviour, luminescent inhibition of Vibrio fischeri and Daphnia magna immobilisation. Although the total content of Cu, Zn and Pb in the soil was large (362, 245 and 1,250 mg/kg dry matter, respectively), these metals were mostly structurally bound (87% for Cu, 81% for Zn and 89% for Pb) and, therefore, scarcely bioavailable. Nonetheless, the D. magna immobilization test using soil leachate showed an EC₅₀ (48 h) of 36.3% (v/v), and the luminescent inhibition of V. fischeri presented an EC₂₀ (15 min) of 45.2% and an EC₂₀ (30 min) of 10.7% (v/v), suggesting a considerable toxic effect. In the direct exposure bioassays, E. fetida avoided the mine soil at the highest concentrations (50%, 75% and 100% v/v). At the same soil concentrations, cress showed negligible growth. The results suggest the need to use a battery of toxicity tests, in conjunction with chemical methods, in order to assess the quality of mine-contaminated soils correctly.     

Fine atmospheric particles emitted by industrial,traffic and urban sources in France: characterization and genotoxicity

Health risks associated with inhalation of fine particulate matter of 2.5 µm in diameter or smaller depend on their atmospheric levels and physicochemical properties. The relationships between chemical compositions and genotoxic activities of particles emitted by mineral industries, traffic and urban sources during summer and winter in the region of Provence-Alpes-Côte d'Azur (France) were investigated.

The fine particles were separated in respect to water-soluble (13 minerals and metals) and organic-extractable (16 polycyclic aromatic hydrocarbons) components that were quantified. The chromosome damaging properties of the hydrophilic and lipophilic extracts were assessed using the centromeric micronucleus assay on a human lung fibroblast cell line.

The composition of the fine particulate matter was variable and depended upon the sources and seasons. Both the hydrophilic and lipophilic extracts induced chromosome damage: (1) in hydrophilic extracts, Ca and Zn affected chromosome losses induction; (2) acenapthylene affected chromosome damage (breakages and losses) induction and naphthalene affected chromosome damage and losses induction in lipophilic extracts without metabolic activation; and (3) benzo[a]pyrene affected chromosome losses induction in lipophilic extracts with metabolic activation. Fine particulate matter arising from coal-fired power station, road traffic, and other urban sources were the most efficient to induce chromosome breakage.     

Application of microcosm and species sensitivity distribution approaches in the ecological hazard assessment of 4-tert-butylphenol

In order to evaluate the ecological hazard of 4-tert-butylphenol (4-TBP), species abundances and physicochemical properties were monitored for 63 days in a microcosm system containing planktonic algae, rotifers, shrimps and Daphnia. The 63 days-NOEC (no observed effect concentration) of 4-TBP for this system was calculated. At the same time, species sensitivity distribution curves were constructed based on the toxicity data of EC₁₀, EC₅₀ and NOEC derived from laboratory single-species toxicity tests, which further gives no obvious hazard concentrations for 95% species in the ecosystem (HC₅). In both the microcosm and the single-species tests, the shrimp (Neocaridina sp.) was the most sensitive species to 4-TBP exposure, while most algae species were relatively insensitive compared to the zooplankton. For the microcosm exposed to 4-TBP, significant changes occurred to the community structure instead of the community function, resulting in a NOEC_microcosm of 265.38?μg?L^–1 which approached the EC₁₀-based HC₅ (0.376?mg?L^–1). Nevertheless, EC₅₀-based HC₅ was higher than the NOEC_microcosm, and the NOEC-based HC₅ was lower. The data showed that the EC₁₀-based HC₅ was protective at the similar level with the result of microcosm for 4-TBP, providing supportive data for chemical risk assessment.     

Community participation in the management of forest reserves in the Northern Region of Ghana

The 1994 forest and wildlife policy of Ghana provides the basis for community participation in forest management through participatory forest management. Even though forest reserves in the Northern Region are said to be managed collaboratively, fringe communities are supposedly involved only in maintenance activities of the reserve boundaries and seedling planting in plantation programmes. The forest reserves are said to be threatened by illegal activities from the fringe communities. This study therefore examined the nature of community participation in the management of forest reserves.

It is a mixed method research in which structured interview schedule, in-depth interview and focus group discussion guides were used for data collection. Respondents comprised community members, forestry staff and NGOs. Communities’ participation was found to be passive and tokenistic and limited to boundary cleaning and providing labour on plantations. There is no formal collaboration between communities and Forest Services Division. Prospects to communities’ participation lie in the continuous flow of benefits and their active involvement in management decisions. Active involvement of communities in all decision-making processes, capacity building of communities and forestry staff, incentive schemes and awareness creation are recommended for promoting community participation in managing forest reserves in Northern Region.     

城市污水厂污泥倾倒对海洋生物的毒性研究

以广州市和佛山市的5个城市污水处理厂的污泥为实验对象,选取费氏弧菌、蒙古裸腹溞、卤虫、裸项栉鰕虎鱼仔鱼4种不同营养级的海洋生物为受试对象,结合化学分析方法,研究广州区域周边污水污泥浸出液的生物毒性效应。结果显示各污水污泥浸出液的毒性均较大,且浸出液的Cu污染浓度较高;广州市污水污泥对4种受试生物的毒性效应要高于佛山市。从污泥毒性对受试生物的选择性方面分析,发现卤虫筛分能力强且灵敏度高,而费氏弧菌则相关性好且方法简捷。研究结果为反映城市污泥的生物毒性强度和选择合适毒性评价受试生物提供基础数据。     

Effects of bisphenol A on Gammarus fossarum and Lumbriculus variegatus in artificial indoor streams

The impact of bisphenol A (BPA) on Gammarus fossarum and Lumbriculus variegatus was studied in four artificial indoor streams (0, 5, 50 and 500?µg?L^?1 BPA, nominal) over 103 days in a pulse–dose exposure scenario (weekly BPA application). For G. fossarum populations at day 103, the proportions of juveniles and of breeding females from the highest BPA treatment were in tendency reduced. For individually exposed gammarid pairs an EC₁₀ of 17?µg?L^?1 BPA (nominal) for the proportion of reproductive females in the fourth brood was determined. During the first three broods, the largest brood size occurred at the highest BPA concentration, whereas in the fourth brood it decreased concentration-dependently (fourth brood EC₁₀?=?5?µg?L^?1 BPA, nominal). Effects on L. variegatus were a reduced population growth (103?d-EC₁₀ of 2?µg?L^?1 BPA, nominal) and an increase in dry weight and the number of segments in large, complete worms.     

多种聚氧乙烯牛脂胺混合物MON 0818的水生环境危害评估：脉冲暴露后沉积物、温度和恢复能力的影响

我们对一种商业表面活性剂混合物(多种聚氧乙烯牛脂胺)MON 0818进行了一系列毒性测试：1. 测定底栖无脊椎动物和鱼类在沉积物存在的情况下受到的毒性;2.测定大型蚤(Daphnia magna)和4种初级生产者经过24 h的脉冲暴露之后的恢复能力;3.鉴定水体温度上升对于2种冷水鱼类所受到MON 0818毒性的潜在影响。在沉积物存在的情况下,5种生物中有3种在最高10 mg/L的浓度下短期(24 h)死亡率为零。其余2种物种的中位有效浓度则显著高于仅对水体进行测试的结果。15 ℃下北极红点鲑(Salvelinus alpinus)的半数有效浓度统计上低于10 ℃下。绿藻(Rhabdocelis subcapitata)和普通小球藻(Chlorella vulgaris)在经过24 h 1 mg/L的暴露后的恢复期中显示出生长延迟的状况,表明该暴露可能存在潜在影响。尽管如此,2个物种的最大绝对生长速率并未改变,表明其均可恢复。1.5 mg/L下的蝾螈共生藻(Oophila sp.)和100 mg/L下的浮萍(Lemna minor)经过24 h的暴露并未显示显著反应。24 h 5 mg/L暴露之后的恢复期中,大型蚤显示出潜在的死亡率。然而存活个体的生殖终端指标并未受到影响。结果表明在沉积物的存在下MON 0818的快速损耗可以减轻对于被暴露生物的效果,在不小于环境中可能出现的MON 0818浓度情况下,24 h暴露以后的生物的完全恢复是可能的。
精选自Jose L. Rodriguez-Gil, Ryan Prosser, Gregory Hanta, David Poirier, Linda Lissemore, Mark Hanson, Keith R. Solomon. Aquatic hazard assessment of MON 0818, a commercial mixture of alkylamine ethoxylates commonly used in glyphosate-containing herbicide formulations. Part 2: Roles of sediment, temperature, and capacity for recovery following a pulsed exposure. Environmental Toxicology and Chemistry: Volume 36, Issue 2, pages 512–521, July 2017. DOI: 10.1002/etc.3558
详情请见http://onlinelibrary.wiley.com/wol1/doi/10.1002/etc.3558/full
     

Evaluation of the toxicity of tetrabromobisphenol A and some of its oxidation products using a micro-scale algal growth inhibition test

A micro-scale algal growth inhibition (μ-AGI) test using a common micro-plate based fluorometric detection was used to demonstrate the effects of humic substances (HSs) on the toxicity of tetrabromobisphenol A (TBBPA) and its oxidative decomposition products 2,5-dibromo-1,4-benzoquinone (2,5-DBBQ), 2,5-dibromohydroquinone (2,5-DBHQ), 2,6-dibromobenzoquinone (2,6-DBBQ), and 2,6-dibromophenol (2,6-DBP) to Pseudokirchneriella subcapitata. The EC₅₀ values were: EC_50(TBBPA) = 7 mg L^?1, EC_50(2,5-DBHQ) = 7 mg L^?1, EC_50(2,5-DBBQ) = 19 mg L^?1, EC_50(2,6-DBP) = 49 mg L^?1, and EC_50(2,6-DBBQ) = 13 mg L^?1. The toxicity of the chemicals was slightly lower in the presence of HA. The toxicity of TBBPA decomposed by a biomimetic catalytic system consisting of iron (III) 5,10,15,20-tetrakis (p-sulfonatophenyl) porphyrin (Fe(III)-TPPS) and KHSO₅ was also evaluated using P. subcapitata and Chlamydomonas reinhardtii.     

Analytik von Umwandlungsprodukten des Schwefellosts (S-LOST)

The results of investigations of the aquatic ecotoxicity of sternutators and their metabolites (phenyl arsenic compounds) are presented. The standardized luminescence inhibition test (LumisTox, Dr. Lange) with the marine bacteriaVibrio fischeri was applied according to the German norm DIN 38412, part 34. All investigated organic AS(III) compounds exhibit EC₅₀-values (50 % inhibition of the luminescence) of less than 1 mg/l, whereas all investigated organic As(V) compounds and inorganic arsenic show EC₅₀-values exceeding 100 mg/l