Cloning and expression of a cDNA coding for catalase from zebrafish (Danio rerio)

A full-length complementary DNA (cDNA) clone encoding a catalase was amplified by the rapid amplication of cDNA ends-polymerase chain reaction (RACE-PCR) technique from zebrafish (Danio rerio) mRNA. Nucleotide sequence analysis of this cDNA clone revealed that it comprised a complete open reading frame coding for 526 amino acid residues and that it had a molecular mass of 59 654 Da. The deduced amino acid sequence showed high similarity with the sequences of catalase from swine (86.9%), mouse (85.8%), rat (85%), human (83.7%), fruit fly (75.6%), nematode (71.1%), and yeast (58.6%). The amino acid residues for secondary structures are apparently conserved as they are present in other mammal species. Furthermore, the coding region of zebrafish catalase was introduced into an expression vector, pET-20b(+), and transformed into Escherichia coli expression host BL21(DE3)pLysS. A 60-kDa active catalase protein was expressed and detected by Coomassie blue staining as well as activity staining on polyacrylamide gel followed electrophoresis.     

利用CRISPR/Cas9系统高效敲除斑马鱼lncRNA基因启动子区

斑马鱼(Danio rerio)长非编码RNA(long non-coding RNA,lncRNA)基因Nondret002679与人(Homo sapiens)肿瘤相关基因间长非编码RNA682基因LNC-PHOX2B-2具有同源序列.本研究以斑马鱼为模型,利用成簇规律间隔短回文重复序列/成簇规律间隔短回文重复序列关联蛋白9(clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9,CRISPR/Cas9)系统,敲除预测的Nondret002679基因启动子区以沉默Nondret0026 79基因的表达,研究IncRNA基因Nondret0026 79在斑马鱼中的调控功能.首先利用启动子区上下游序列设计靶向不同位点的向导RNA(guide RNA) gR1、gR2、gR3、gR4、gR5和gR6.人工合成gRNA转录模板,体外转录为gRNA,与Cas9 mRNA一起显微注射到斑马鱼卵中.PCR鉴定28尾2月龄斑马鱼发现,11尾发生敲除,敲除率为39％.繁殖启动子区敲除的杂合鱼,获得33尾F1代,经鉴定有6尾F1斑马鱼启动子区缺失,其中3尾缺失是在两条同源染色体上.该初步研究表明,CRISPR/Cas9系统可高效敲除lncRNA基因的启动子区,并且这种敲除可以遗传至下一代,为研究lncRNA功能提供了一个有效的基因编辑工具.     

Integrating the fish embryo toxicity test as triad element for sediment toxicity assessment based on the Water Framework Directive approach

Purpose  

The objective of this study was to complement analyses according to the European Union Water Framework Directive (WFD) with a sediment toxicity analysis as part of an integrated river assessment. To this end, Hessian water courses were analyzed using the sediment quality triad concept according to Chapman with chemical analyses, in situ effect evaluations, and ecotoxicological assessments. For the ecotoxicological assessment (fish embryo toxicity test with Danio rerio), a new evaluation scheme was developed, the fish teratogenicity index (FTI), that allows for a classification of sediments into ecological quality classes compliant to the WFD.     

Chronic toxicity of unresolved complex mixtures (UCM) of hydrocarbons in marine sediments

Background, Aim and Scope  Unresolved complex mixtures (UCM) of hydrocarbons, containing many thousands of compounds which cannot be resolved by conventional gas chromatography (GC), are common contaminants of sediments but little is known of their potential to affect sediment-dwelling organisms. Evidence exists for reduced health status in mussels, arising from aqueous exposure to aromatic UCM components acting through a narcotic mode of action. However, UCM contaminants in sediments may not be sufficiently bioavailable to elicit toxic effects. The aim of our study was therefore to measure the sublethal effects of chronic exposure to model UCM-dominated oils at environmentally realistic concentrations and compare this to effects produced by a UCM containing weathered crude oil. A further aim was to determine which, if any, fractions of the oils were responsible for any observed toxicity. Materials and Methods  Whole oils were spiked into estuarine sediment to give nominal concentrations of 500 μg g⁻¹ dry weight. Juveniles of the estuarine amphipod Corophium volutator were exposed to the contaminated sediment for 35 days and their survival, growth rate and reproductive success quantified. Using an effect-directed fractionation approach, the oils were fractionated into aliphatic and two aromatic fractions by open column chromatography and their toxicity assessed by further chronic exposures using juvenile C. volutator. Results  The growth rates of amphipods were reduced following exposure to the oils although this was only statistically significant for the weathered oil; reproductive success was reduced by all oil exposures. Sediment spiked with UCM fractions also caused reduced growth and reproduction but no particular fraction was found to be responsible for the observed toxicity. Survivorship was not affected by any oil or fraction. Discussion  The study showed that chronic exposure to sediments contaminated by UCM-dominated oils could have population level effects on amphipods. The observed effects could not be explained by hydrocarbons resolved by conventional GC and effects were similar for both UCM-dominated and weathered oils. All of the fractions appeared to contribute to the observed effects; this is in contrast to previous research which had shown that an aliphatic UCM did not cause adverse effects in mussels. Conclusions  To our knowledge, this is the first study to demonstrate population-level effects arising from exposure to sediments contaminated by realistic environmental concentrations of UCM hydrocarbons. The results are consistent with many compounds, at very low individual concentrations, contributing towards the overall observed toxicity. Recommendations  Risk assessments of contaminated sediments should take into account the contribution towards the potential for toxic effects from UCM hydrocarbons. Studies into sediment contamination should report both aliphatic and aromatic UCM concentrations to aid risk assessments. ESS-Submission Editor: Henner Hollert (hollert@uni-heidelberg.de) This paper has been developed from a presentation at SETAC Europe 16^th Annual Meeting 2006 held at the The Hague, The Netherlands.     

Evaluation of the potential toxicity (acute and chronic) of sediments from abandoned uranium mine ponds

Background, Aim and Scope  

The superficial aquatic system of the Cunha Baixa uranium mine area is comprised by the flooded mine pit (M), which receives the acidic mine effluent resultant from in situ leaching of pore ore, a pond where this effluent is neutralised (T), and a potential reference pond (Ref). As part of the first tiers of an ecological risk assessment that is being performed in this area, the aim of this work was to evaluate the potential sediment toxicity of these ponds.     

NaF和PFOS对斑马鱼肝脏抗氧化能力、非特异性免疫及组织结构的影响

为探讨有机氟化物和无机氟化物单一及联合暴露对斑马鱼(Danio rerio)肝脏的毒性效应,本研究将雄性斑马鱼随机分为对照组、氟化钠(NaF,无机氟)暴露组、全氟辛烷磺酸(PFOS,有机氟)暴露组、NaF+PFOS(无机氟及有机氟联合)暴露组,经15、30 d暴露试验后,检测了血液硝基蓝四氮唑(NBT)阳性细胞数及肝脏...     

Evaluation of extraction methodologies for corn kernel (Zea mays) DNA for detection of trace amounts of biotechnology-derived DNA

Sensitive and accurate testing for trace amounts of biotechnology-derived DNA from plant material requires pure, high-quality genomic DNA as template for subsequent amplification using the polymerase chain reaction (PCR). Six methodologies were evaluated for extracting DNA from ground corn kernels spiked with 0.1% (m/m) CBH351 (StarLink) corn. DNA preparations were evaluated for purity and fragment size. Extraction efficiency was determined. The alcohol dehydrogenase gene (adh1) and the CBH351 (cry9C, 35S promoter) genes in the genomic DNA were detected using PCR. DNA isolated by two of the methods proved unsuitable for performing PCR amplification. All other methods produced some DNA preparations that gave false negative PCR results. We observed that cornstarch, a primary component of corn kernels, was not an inhibitor of PCR, while acidic polysaccharides were. Our data suggest that amplification of an endogenous positive control gene, as an indicator for the absence of PCR inhibitors, is not always valid. This study points out aspects of DNA isolation that need to be considered when choosing a method for a particular plant/tissue type.     

The impact of gas extraction on landfill-generated methane gas levels

The changes measured in landfill-generated CH₄ gas levels in response to continuous pumping from an augered borehole in the refuse are described. The results of statistical analyses of concentration and pressure levels at a series of probes located radially outward from the gas extraction well are used to characterize the temporal and spatial variations. A drawdown curve arising from the continuous pumping is apparent and is quantified as a series of cones of varying impacts on percentages of CH₄. The results are indicative of a fairly free flow of gas through the landfill.     

Geochemistry of stream sediments within the reclaimed coastal floodplain as indicator of anthropogenic impact (River Neretva,Croatia)

Purpose

This study used multi-element signatures of stream sediments to assess both natural and human-induced impact on fluvial system in the River Neretva delta receiving environment over time. The river basin actually comprises several sub-catchments, and the geochemical features of major elements, trace metals radiometric and mineralogical characterisation of river bed sediments were used to assist the interpretation of the environment of deposition and its subsequent modifications caused by various anthropogenic pressures within the river basin.

Materials and methods

Five sites were chosen for sediment sampling at key locations within the study area with assumed undisturbed, continuous sedimentation process. At each of the sites, three representative cores were taken by scuba divers. Sample sites were selected in order to reflect the influence of different sub-catchments they belong to and the land-use pattern of the surrounding area. Samples were analysed for pH, redox-potential, granulometry, mineralogy, thermogravimetry, major and trace element concentrations and radionuclide activities. The univariate and multivariate statistics were applied. The geochemical normalisation of data was done using Al, the procedure based on calculation of the regression line of the metal on the normaliser followed by testing the ratios metal/normaliser on all data-points.

Results and discussion

All studied sediments are classified as silt, ranging from clayey silt to silt and sandy silt. Mineralogically, the sediments were dominated by carbonates and quartz. The chemical contaminant data are generally of good quality, mostly below guideline levels. Sedimentation rates were estimated using vertical distribution of ¹³⁷Cs activities. Normalisation of TMs done by using Al shows strong R ² _adj values for the regressions of Al and V, Al and Cr, and Al and Ni. However, Al cannot fairly explain the fluctuation of the concentrations of Cd, Cu, Pb and Zn in sediment cores from all of the sampling sites. Generally, inorganic scavengers such as clay minerals followed by Fe and Mn oxides and S (pyrite and gypsum) seem to be dominant factors controlling TMs in studied sediments.

Conclusions

Although the River Neretva delta occupies a rather small area, the geochemical features of major and trace elements and ¹³⁷Cs activities show complex sediment provenances. Each of the sampling sites reflect exactly different effects of anthropogenic intervention that particularly refer to the changes in river morphology and ecology, along with the altered flow regimes within the catchment on sediment loads and quality.

     

The dioRAMA project: assessment of dioxin-like activity in sediments and fish (Rutilus rutilus) in support of the ecotoxicological characterization of sediments

Introduction

Given the complex interactions of re-suspension processes and bioavailability of sediment-bound pollutants such as dioxin-like chemicals, there is need for a better integrative understanding of the cause–effect relationship of these pollutants. Currently, the majority of studies investigating potential risks of these chemicals only focus on characterizing sediment extracts via in vitro bioassays, thereby disregarding bioavailability, uptake, metabolism, and elimination rates of these compounds in vivo. To determine to which extent mechanism-specific effects in vitro reflect possible adverse effects in vivo, the research project dioRAMA, involving partnership between the Institute for Environmental Research of RWTH Aachen University and the Department Biochemistry/Ecotoxicology of the German Federal Institute of Hydrology, was established.

Methods

Animals from an elevated trophic level—common roach (Rutilus rutilus)—will be exposed to sediments from two major German rivers. Exposure will be performed in a system that enables a concurrent monitoring of environmental parameters. In parallel, in vitro studies will be conducted to determine dioxin-like potentials of sediment and fish extracts from the in vivo exposure experiments using different cell lines with varying endpoints. Moreover, extract fractionation procedures, using the strategy of effect-directed analysis, will enable the detection of specific contaminant groups responsible for the biological activity observed.

Conclusion

A closer interconnection between applied ecotoxicological science and regulatory needs will facilitate the improved assessment of dioxin-like compounds in sediment and biota. Consequently, this will enable their application in sediment management programs, which is one of the main goals of the dioRAMA project.     

Evaluation of toxicity risk of polycyclic aromatic hydrocarbons (PAHs) in crops rhizosphere of contaminated field with sequential extraction

Purpose

The assessing bias of rhizosphere effect on polycyclic aromatic hydrocarbons (PAHs) degradation in soils would come out from formation of nonextractable PAHs and extractability difference of various solvents. The aim of this study was to evaluate the role of rhizosphere effect in long-term PAHs polluted soils by using sequential extraction approach.

Material and methods

The scheme of sequential extraction included methanol/water extractable PAHs, butanol extractable PAHs, DCM extractable PAHs, humic acid-bound PAHs, crude humin-bound PAHs, and organic-C enriched humin-bound PAHs. PAHs in plant tissues were extracted by dichloromethane after saponifying. The correlations between PAHs in plant tissues and sequentially extracted fractions were generated by partial least squares regression.

Results and discussion

The profiles of sequentially extracted PAHs varied with plant species. The discrepancy of toxicity equivalency concentrations between rhizosphere and bulk soils was much more significant than that of total PAHs concentrations. In partial least squares regression models, the concentration of PAHs in plant tissues was correlated with fractions strongly associated with soil.

Conclusions

The novelty of this study is the evaluation of concentration and toxicity equivalency concentration of PAHs in rhizosphere of crops sampled in a field polluted with PAHs for long term. This study has highlighted more significant role of rhizosphere in cleanup of cancerogenic toxicity of soil than amount of PAHs in polluted soils.     

Magnetic spherules in sediments of the karstic Dobra River (Croatia)

Purpose

The paper describes an unusual finding of magnetic particles in stream sediments of the karstic Dobra River (Croatia). It aims to investigate the magnetic susceptibility properties of river sediments and to find links with their mineralogical and chemical composition. The goal of our research was to suggest the possible origin of magnetic particles in the river sediments within the Dinaric karst region, which to our knowledge was not exposed to metal manufacturing processes.

Materials and methods

A preliminary, exploratory sediment sampling programme was undertaken. Sediments were collected near the channel bank (from the top layer) at 16 representative stations distributed along the length of the Dobra River (110 km). Sediments were air-dried and passed through 2-mm and 63-μm sieves, and analysed for magnetic susceptibility (and Curie temperature), isothermal remanent magnetism (IRM), stereo-microscopy of separated magnetic grains, mineralogical analysis (using X-ray diffraction), and chemical analysis (using inductively coupled plasma–mass spectrometry).

Results and discussion

Increased magnetic susceptibility and IRM values were observed mostly in the sediments of the Upper Dobra. Thermomagnetic curves show a distinctive Curie-point of magnetite at 580 °C. Additional transformation observed at 520–560 °C derives from titanomagnetite. There was no significant correlation between magnetic susceptibility and Fe. Magnetic particles from the Dobra River sediments contain pyroxene, plagioclase, hematite and quartz, in addition to magnetite. White spherules within magnetic grains are also present. The major constituent of five separated magnetic spherules is Fe; the minor constituents are Al, Ca, Mg and Si, and there are numerous trace elements (Ba, Cr, K, Mn, Na, Ni, Ti and V). The ratio Ni/ Fe versus Cr/Fe suggests that the magnetic spherules are impactites.

Conclusions

Magnetic spherules were discovered for the first time in stream sediments of the sinking karstic Dobra River, a region where anthropogenic sources for that contribution are absent. Preliminary results point to a possible impactite, formed either by a shock event caused by a meteorite impact or by volcanic processes. The presence of magnetic spherules in the fluvial sediments of the Upper Dobra River represents a new and exciting finding and deserves further field work and laboratory research.     

The bioavailability and toxicity of ZnO and Ni nanoparticles and their bulk counterparts in different sediments

Purpose

The intensive development of nanotechnology raises a question of the potential consequences of the presence of nanoparticles (NPs) in the different components of the environment, including sediments. The aim of this study was to evaluate the toxicity of nanoparticles of ZnO and Ni and their bulk counterparts in bottom sediments (SD1, SD2) with different properties collected from the Vistula River in Poland.

Materials and methods

Sediment samples with NPs at a concentration of 100 mg kg^?1 were incubated for 17 months in the dark or under a photoperiod of 12 h light/12 h dark. The Microtox^® (bacteria, Vibrio fischeri) and OSTRACODTOXKIT F^? (ostracods, Heterocypris incongruens) tests were used to evaluate toxicity. In addition, the contents of Zn and Ni were determined in extracts (H₂O and CaCl₂) of the bottom sediments.

Results and discussion

The Zn concentration was much lower in the SD1 sediment with the addition of NPs/bulk particles (30–230 μg kg^?1) compared to the SD2 sediment (280–1140 μg kg^?1). The toxicity of ZnO and Ni was determined by the type of bottom sediment and the parameter studied. Both nano- and bulk-ZnO and Ni caused the mortality of H. incongruens at a level of 13.3–53.3 %. The influence of ZnO and Ni on the growth of H. incongruens was observed to be the opposite. ZnO resulted in growth stimulation, while Ni resulted in growth inhibition of H. incongruens. Both ZnO and Ni stimulated V. fisheri luminescence. In most cases, the incubation of ZnO and Ni under the photoperiod increased the toxicity or decreased the stimulation of V. fisheri bioluminescence and H. ingongruens growth compared to the dark-incubated sediments.

Conclusions

The study provides new and important information on the ecotoxicological effects of ZnO and Ni nanoparticles in different sediments and under various environmental conditions that may be useful for the risk assessment of this new group of contaminants.

     

Effect of fermentation on Sweetpotato (Ipomoea batatas) toxicity in mice

Unfortunate bovine fatalities occurring after ingestion of mold-damaged sweetpotatoes preclude the use of the culled tubers in livestock feed. In cattle, mold-damaged sweetpotatoes induce an acute respiratory distress syndrome resulting in asphyxiation. Because of this potential toxicity and the general abundance of culled sweetpotatoes, the detoxification efficacy of ensiling was explored since it is an easy and economically viable technique often applied to preserve livestock feed. Sweetpotato slices with or without mold damage were stored either frozen (to represent unfermented samples) or fermented for 6 weeks at room temperature. Following fermentation, organic extracts were generated for administration to mice. Thirty hours following administration of the extracts, mice were evaluated for gross and microscopic lesions affecting the lungs, liver, and kidneys. Fermentation of 6 weeks duration was observed to inadequately eliminate the lung, liver, and kidney toxicity caused by mold-damaged sweetpotatoes. In fact, fermentation exacerbated the hepatotoxicity of mold-damaged sweetpotatoes. This is also the first demonstration that sweetpotato regions lacking visible mold damage can induce lung and kidney injury, which, however, is preventable by fermentation.     

DNA content in embryo and endosperm of maize kernel (Zea mays L.): impact on GMO quantification

PCR-based techniques are the most widely used methods for the quantification of genetically modified organisms (GMOs) through the determination of the ratio of transgenic DNA to total DNA. It is shown that the DNA content per mass unit is significantly different among 10 maize cultivars. The DNA contents of endosperms, embryos, and teguments of individual kernels from 10 maize cultivars were determined. According to our results, the tegument's DNA ratio reaches at maximum 3.5% of the total kernel's DNA, whereas the endosperm's and the embryo's DNA ratios are nearly equal to 50%. The embryo cells are diploid and made of one paternal and one maternal haploid genome, whereas the endosperm is constituted of triploid cells made of two maternal haploid genomes and one paternal haploid genome. Therefore, it is shown, in this study, that the accuracy of the GMO quantification depends on the reference material used as well as on the category of the transgenic kernels present in the mixture.     

The use of a microbial contact toxicity test for evaluating cadmium bioavailability in soil

Background, Aims and Scope

Bioavailability of toxic compounds in soil can be defined as the fraction able to come into contact with biota and to cause toxic effects. The contact toxicity tests may detect the total toxic response of all bioavailable contaminants present in a sample. The objectives of this study were to evaluate the use of microbial contact toxicity tests for cadmium bioavailability assessment and to evaluate the relationship between sorption, soil characteristics and cadmium bioavailability.

Methods

A test soil bacterium,Bacillus cereus, was put in direct contact with the solid sample. Four unpolluted soils were selected to provide solid samples with a variety of physicochemical characteristics. The toxicity and sorption behaviour of cadmium spiked to the soil samples were determined.

Results, Discussion and Conclusions

A significant correlation between contact toxicity test results and partitioning of cadmium in the soil samples (r²= 0.79, p <0.05; n = 26) was found. The results confirm that the bioavailability of cadmium in soil depends on its sorption behaviour. Cadmium sorbed to the cation exchange sites associated with fulvic acids is non-bioavailable in the toxicity test employed in this study. It is concluded that the microbial contact toxicity test is a suitable tool for detecting cadmium bioavailablity in the soils used in this study.

Outlook

The application of microbial contact toxicity tests for bioavailability assessment can be very useful for the risk identification and remediation of soil-associated contaminants.     

A comparison of nickel toxicity to pre-exposed earthworms (Eisenia fetida, oligochaeta) in two different test substrates

Earthworms are soil living organisms of high ecological importance. For that reason, earthworms can be considered as feasible biological indicators for many pollutants in soils. Soils are extremely complex and dynamic systems influenced by a number of different abiotic and biological factors determining the effects of potentially toxic substances. To be able to evaluate the toxicity of a single substance to soil living organisms such as earthworms, soil-related influences and interactions need to be excluded. For that purpose, the use of defined, artificial soil free substrates has been widely established. In this study, a new artificial substrate based on the knowledge gained by the application of different methods, in particular the exposure in reconstituted water resembling natural ground water and an agar medium initially developed to void the guts of earthworms, is proposed. Eisenia fetida have been exposed for 96 h to a medium consisting of 1.5% normal melting agarose added to reconstituted ground water. For validation of the substrate, the effects of nickel toxicity, a substance known to be toxic to E. fetida, were evaluated. In addition, to investigate the possible establishment of resistance or adaptation, as well as cross-resistance, E. fetida individuals with a history of previous exposure (more than 10 generations) to nickel and manganese were exposed to different concentrations of nickel. Both media, one consisting of reconstituted ground water [Kiewiet, A.T., Ma, W.-C., 1991. Effect of pH and calcium on lead and cadmium uptake by earthworms in water. Ecotoxicology and Environmental Safety 21, 32-37] and the other of reconstituted ground water plus agar, seemed equally suited for the evaluation of intrinsic effects of nickel and manganese on E. fetida. With regard to the possible development of resistance, E. fetida did not show an increased tolerance towards nickel in spite of being exposed to elevated levels for more than 10 generations; to the contrary, worms with a history of exposure to nickel showed an increased sensitivity towards nickel. No indications of cross-resistance between manganese and nickel pre-exposed worms were detected.     

Chemical patterns in sediments of ancient Theodosius Harbour (Istanbul)

Purpose

The use of fossil fuels, cement production and the reduction of forest areas cause a high amount of CO₂ emissions to the atmosphere which in turn causes the ocean to be acidified. Acidity of seawater can directly change sediment properties. It is expected that the average pH value of the ocean surface water will decrease between 0.3 and 0.5 pH units according to the projection to year 2100. This study aimed to make a contribution to the understanding of long-term pollution trends. In the study, sediment samples from Neolithic Era, Early Byzantine Era and Byzantine Era from archaeological excavations jointly conducted by Istanbul Archaeological Museums and the Istanbul University Department of Conservation of Underwater Cultural Heritages were investigated.

Materials and methods

The sediment samples were taken from ancient Theodosius Harbour (5000 BC). Major elements (Si, Al, Fe, Mg, Ca, K, Na, Mn, Ti), rare earth elements (Tb, Yb, Eu, Dy, Tm) and toxic elements (As, Cr, Co, Cu, Ni, Pb and Zn) in sediment samples were determined by X-ray fluorescence spectrometer. The chemical abundance of the ancient sediments was evaluated with the ecological risk factor and geo-accumulation index.

Results and discussion

The sediment samples from the Neolithic Era reflect the contribution of both parent rock and also anthropogenic pollution. In the Early Byzantine and Byzantine Era, the development of the industry has increased the basic element concentrations in the environment and potential ecological risk and geo-accumulation indices. As, Cu, Cr, Zn, Ni and Co contents of Neolithic Era samples were found to be lower than Early Byzantine and Byzantine Era.

Conclusions

The obtained the results showed that the toxic elements in the Neolithic Era, which the industry never developed, started to rise and increased concentrations of Ni by about two and a half times, Zn four times, Pb two times, Cr two times, Co six times and As three times in the Early Byzantine and Byzantine Eras. The concentrations of major elements (Al, Ba, Ca, Fe, K, Mg, Mn, Na, Si) did not show any significant difference during these three eras.

     

The influence of soil characteristics on the toxicity of four chemicals to the earthworm Eisenia fetida andrei (Oligochaeta)

Summary The acute toxicity of Cd (chloride), chloroacetamide, 3,4-dichloroaniline and pentachlorophenol to the earthworm Eisenia fetida andrei was determined using the OECD (1984) artificial soil and contact testing procedures. To investigate the influence of two soil characteristics (pH and organic-matter content), the toxicity of the chemicals was also determined in two natural sandy soils. It is concluded that the filter-paper contact test cannot be recommended to predict earthworm toxicity of these chemicals in soil. Toxicity in soil was influenced by both pH and organic-matter content. Differences between LC₅₀ values in the high-organic-matter artificial soil and in an acid, low-organic-matter sandy soil were, however, not greater than a factor of 3–4. The results of this study therefore support the use of a well-defined artificial soil substrate for standardized earthworm toxicity tests.     

Erratum to: Evaluation of toxicity risk of polycyclic aromatic hydrocarbons (PAHs) in crops rhizosphere of contaminated field with sequential extraction

Journal of Soils and Sediments -