Use Of Biological Indicators Research Articles

Communities of aquatic organisms in the system of ecological monitoring of streams at the Vostochny Cosmodrome (Russia)

The current data on the ecological state of streams at the launch site of the Vostochny Cosmodrome with the use of biological indicators are presented. Recommendations on the surface water biomonitoring of the cosmodrome and the booster rocket drop zones are given. It is shown that the system of biological monitoring of the cosmodrome, as a part of the Roscosmos environmental monitoring, should be coordinated with the Roshydromet monitoring.

Biogeochemical characterization of surface waters in the Aljustrel mining area (South Portugal).

Aljustrel mining area (South Portugal) is a part of the Iberian Pyrite Belt and encloses six sulfide mineral masses. This mine is classified of high environmental risk due to the large tailings' volume and acid mine drainage (AMD)-affected waters generated by sulfides' oxidation. The use of biological indicators (e.g., diatoms) revealed to be an important tool to address the degree of AMD contamination in waters. Multivariate analysis has been used as a relevant approach for the characterization of AMD processes. Cluster analysis was used to integrate the significant amount and diversity of variables (physicochemical and biological), discriminating the different types of waters, characterized by the high complexity occurring in this region. The distinction of two main marked phenomena was achieved: (1) the circumneutral-Na-Cl water type (sites DA, PF, BX, BF, RO, CB), expressing the geological contributions of the Cenozoic sediments of Sado river basin, with high diatom diversity (predominating brackish diatoms as Entomoneis alata); and (2) the acid-metal-sulfated water type (sites BM, JU, RJ, AA, MR, BE, PC, AF), reflecting both the AMD contamination and the dissolution of minerals (e.g., silicates) from the hosting rocks, potentiated by the extremely low pH. This last group of sites showed lower diatom diversity but with typical diatoms from acid- and metal-contaminated waters (e.g., Pinnularia aljustrelica). In addition to these two water types, this hierarchical classification method also allowed to distinguish individual cases in subclusters, for example, treated dams (DC, DD), with alkaline substances (lime/limestone), that changed the physicochemical dynamics of the contaminated waters.

The Bugs Don't Lie.

Sterilization is a critical process in the preparation of many drug products. Its execution and validation are addressed in numerous regulatory, pharmacopeial, and industry documents. EMA Annex 1: Manufacture of Sterile Medicinal Products stands alone in giving clear preference to physical measurements over those obtained from biological indicators. This paper reviews principles behind sterilization processes outlining the differences between physical and biological measurements as well as their relationship to each other. The assumptions associated with the use of physical measurement are explored and their derivation from microbiological results is traced with the intent of reaffirming the primacy of biological evidence. The arguments and objections to the use of biological indicators in sterilization are reviewed and deconstructed.LAY ABSTRACT: Sterilization validation is required by regulatory agencies around the globe. The accepted principles are derived from those originally established in the United States and the United Kingdom during the 1970s. Unfortunately, these have evolved into conflicting expectations. The U.K. placed greater emphasis on physical measurements initially in HTM-10, and this is reflected in the European Medicines Agency's Annex 1 statements for their preeminence over biological data. Practices, primarily in the U.S., give preference to microbiological challenges as confirmation of lethality. This paper reviews sterilization fundamentals and describes the relationship between physical and biological data. It critiques the various arguments for the superiority of physical measurements and supports why microbiological evidence should take precedence.

Applying Soil Health Indicators to Encourage Sustainable Soil Use: The Transition from Scientific Study to Practical Application

The sustainable management of land for agricultural production has at its core a healthy soil, because this reduces the quantity of external inputs, reduces losses of nutrients to the environment, maximises the number of days when the soil can be worked, and has a pore structure that maximises both the retention of water in dry weather and drainage of water in wet weather. Soil health encompasses the physical, chemical, and biological features, but the use of biological indicators is the least well advanced. Sustainability also implies the balanced provision of ecosystem services, which can be more difficult to measure than single indicators. We describe how the key components of the soil food web contribute to a healthy soil and give an overview of the increasing number of scientific studies that have examined the use of biological indicators. A case study is made of the ecosystem service of water infiltration, which is quite an undertaking to measure directly, but which can be inferred from earthworm abundance and biodiversity which is relatively easy to measure. This highlights the difficulty of putting any monitoring scheme into practice and we finish by providing the considerations in starting a new soil health monitoring service in the UK and in maintaining biological monitoring in The Netherlands.

SURVEY OF INDUSTRIAL WASTEWATER TREATMENT PERFORMANCE WITH BIOLOGICAL MONITORING OF PROTOZOA IN THE INDUSTRIAL PARK OF ABADAN

Industrial wastewater is of particular importance. In most wastewater treatments, physicochemical parameters are used to determine the performances which are costly while protozoa can be used as less expensive biological indicators to determine the efficiency of the treatment plant. The purpose of this study was to investigate the relationship between protozoa and physic-chemical characteristics of the Abadan wastewater treatment industry. Samples were collected from wastewater stabilization ponds in the Abadan industrial park. A total of 66 samples for biochemical and chemical tests and protozoa counts were taken. The sites of sampling were influent of sewage and effluent from maturation pond. For the parameters from influent, first 300 mL of samples was collected in depths of 0.1, 0.35 and 1 m and then mixed to provide a composite sample. 300 mL sample was directly taken from the effluent. The results of this study indicate that there is a positive relationship between the number and population percentage of amoeba and mastigophora (flagellate) with BOD and COD, whereas is the negative relationship between sticking ciliates with BOD and COD. Furthermore there is a positive relation between DO, the percentage, number of ciliates and amoeba population and there is a correlation, with flagellate population. Increase of flagellate numbers is indicative of high effluent Kjeldahl nitrogen. There was also an increase of input TSS and amoeba population percentage and a reduction of free ciliates numbers. The type and abundance of protozoa in industrial wastewater treatment following biological methods is an indicator of the system performance and effluent quality. This study shows the use of biological indicators can be used for monitoring as a much cheaper alternative resulting in a better economy. It is also a good indicator for the detection of toxic materials entering the plant or refinery and also its organic load shocks.

Wetland management using microbial indicators

The use of biological indicators to monitor the health and functioning of wetlands has been an ongoing goal of wetland scientists and managers, and has focused primarily on monitoring the changes in macroorganisms, due to the relative ease of identifying and counting them. In recent years, the establishment of high-throughput sequencing techniques, development of assays for specific functional genes, and better quantitative measures are making it easier to get extensive diversity profiles and more robust abundance estimates of various microbial communities, and empowers us to explore wetland microbiomes and their role in ecosystem function. This heuristic search enables us to illuminate a spot light on minor populations of microbial communities, which were difficult to be scrutinized by more traditional molecular tools. Monitoring microbial indicators in response to nutrient loading, pollutants and redox potential is beneficial for wetland ecosystem management. Microbial populations can serve as the most sensitive and rapid bioindicator in response to various environmental changes. Evaluation of wetland condition and restoration cannot be met effectively by a single physical, chemical or biological parameter but a combination of multiple attributes is effective for robust wetland assessment and management. Various functional groups of microorganisms can be used as wetland assessment tools and provide a more profound understanding of microbial population dynamics and various direct microbial activity measurements. Understanding of the microbial communities controlling biogeochemical cycles in constructed wetlands could support optimizing performance of these promising treatment systems. This review focuses on a potential use of microorganisms as effective biological indicators for wetland management.

Use of biological indicators of soil health to estimate reactive nitrogen dynamics in long-term organic vegetable and pasture systems

Diverse crop rotations, cover crops and the possibility of integrating livestock make organic systems potentially more sustainable than other agroecosystems. Lower reactive nitrogen (N) in organic systems minimizes the potential for N losses. However, addition of organic manures and residues containing mineralizable N and carbon (C) have the potential to enhance nitrous oxide (N2O) emissions. We conducted a 39 d laboratory incubation to assess key microbiological drivers controlling nitrification and denitrification in long-term organic agroecosystems during simulated freeze-thaw cycles. Soils were collected from two annual organic vegetable systems receiving 1) mixed-compost, or 2) broiler litter and 3) an organic perennial pasture system cropped to vegetables every third year. Soil microcosms amended with 15N labelled sugar beet residue or unamended were maintained at 40, 60 and 80% of water filled pore space (WFPS). Significant N2O was emitted (4287–6138 μg kg−1soil) via denitrification from amended soil microcosms at 3 °C and 80% WFPS. Archaeal (AOA) and bacterial (AOB) nitrifier amoA gene copies were affected by temperature and reactive N species during freeze-thaws. Long-term organic vegetable cropping systems receiving mixed-compost additions had the potential to accumulate C and immobilize excess reactive soil N (particularly nitrates) thereby improving soil health and reducing N2O emissions.

Modern Ecological Condition Of The River Basin Of The Seversky Donets Within The Kharkiv Region

Purpose.The testing the method of environmental assessment of surface water quality in terms of the use of biological indicators. Methods. Biological and hydrobiological. Results. To evaluate used quantitative and structural indicators of zoobenthos (TBI, BBІ), zooplankton (saprobity index) and phytoplankton (saprobity index, biomass and chlorophyll «a»). The results of the environmental assessment of the quality of waters of the river Seversky Donets River and its major tributaries within the Kharkiv region on biological indicators of surface water quality, which are used in the method of environmental assessment of surface water quality (edition of 2012). The values of the generalized biological index (ІБ) of the average values of indicators show that the water researched areas of the rivers belong to the II and III water quality classes and graded as "good" and "moderate" as "clean" and "contaminated" by the degree of purity (contamination). Areas with the worst values of biological indicators summarizing experiencing the greatest anthropogenic load. BBІ more sensitive reacted to anthropogenic pressure and had a larger range of changes than TBI. Conclusions. In assessing the ecological status of water bodies is absolutely necessary to consider the role of the biological component to display the actual state of aquatic ecosystems. In assessing the ecological status of water bodies is absolutely necessary to consider the role of the biological component to display the actual state of aquatic ecosystems, which reflects the degree of wellbeing ecosystem of the water body as a whole.

Integrating geochemical (surface waters, stream sediments) and biological (diatoms) approaches to assess AMD environmental impact in a pyritic mining area: Aljustrel (Alentejo, Portugal)

Aljustrel mines were classified as having high environmental hazard due to their large tailings volume and high metal concentrations in waters and sediments. To assess acid mine drainage impacted systems whose environmental conditions change quickly, the use of biological indicators with short generation time such as diatoms is advantageous. This study combined geochemical and diatom data, whose results were highlighted in 3 groups: Group 1, with low pH (1.9–5.1) and high metal/metalloid (Al, As, Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn; 0.65–1032mg/L) and SO4 (405–39124mg/L) concentrations. An acidophilic species, Pinnularia aljustrelica, was perfectly adapted to the adverse conditions; in contrast, teratological forms of Eunotia exigua were found, showing that metal toxicity affected this species. The low availability of metals/metalloids in sediments of this group indicates that metals/metalloids of the exchangeable fractions had been solubilized, which in fact enables metal/metalloid diatom uptake and consequently the occurrence of teratologies; Group 2, with sites of near neutral pH (5.0–6.8) and intermediate metal/metalloid (0.002–6mg/L) and SO4 (302–2179mg/L) concentrations; this enabled the existence of typical species of uncontaminated streams (Brachysira neglectissima, Achnanthidium minutissimum); Group 3, with samples from unimpacted sites, showing low metal/metalloid (0–0.8mg/L) and SO4 (10–315mg/L) concentrations, high pH (7.0–8.4) and Cl contents (10–2119mg/L) and the presence of brackish to marine species (Entomoneis paludosa). For similar conditions of acidity, differences in diversity, abundance and teratologies of diatoms can be explained by the levels of metals/metalloids.

Identification of sensitive indicators to assess the interrelationship between soil quality, management practices and human health

Abstract. Soil quality (SQ) assessment has long been a challenging issue, since soils present high variability in properties and functions. This paper aims to increase the understanding of SQ through the review of SQ assessments in different scenarios providing evidence about the interrelationship between SQ, land use and human health. There is a general consensus that there is a need to develop methods to assess and monitor SQ for assuring sustainable land use with no prejudicial effects on human health. This review points out the importance of adopting indicators of different nature (physical, chemical and biological) to achieve a holistic image of SQ. Most authors use single indicators to assess SQ and its relationship with land uses – soil organic carbon and pH being the most used indicators. The use of nitrogen and nutrient content has resulted sensitive for agricultural and forest systems, together with physical properties such as texture, bulk density, available water and aggregate stability. These physical indicators have also been widely used to assess SQ after land use changes. The use of biological indicators is less generalized, with microbial biomass and enzyme activities being the most selected indicators. Although most authors assess SQ using independent indicators, it is preferable to combine some of them into models to create a soil quality index (SQI), since it provides integrated information about soil processes and functioning. The majority of revised articles used the same methodology to establish an SQI, based on scoring and weighting of different soil indicators, selected by means of multivariate analyses. The use of multiple linear regressions has been successfully used for forest land use. Urban soil quality has been poorly assessed, with a lack of adoption of SQIs. In addition, SQ assessments where human health indicators or exposure pathways are incorporated are practically inexistent. Thus, further efforts should be carried out to establish new methodologies to assess soil quality not only in terms of sustainability, productivity and ecosystem quality but also human health. Additionally, new challenges arise with the use and integration of stable isotopic, genomic, proteomic and spectroscopic data into SQIs.

Impacts and indicators of change in lotic ecosystems

Fresh waters have seen the largest decline in biodiversity of any ecosystem, with lotic ecosystems particularly impacted by human activities. The main drivers of environmental change relate primarily to agriculture, urbanization, and industrial production that have resulted in severe habitat degradation in streams and rivers worldwide. The increasing impact of climate change and invasive species has put further pressure on these systems. For more than a century, status of rivers and streams has been assessed using biological indicators and represents a prime example of applying ecological knowledge to address societal issues. Today, legislative regulations and water management rely primarily on measurements of ecological status through the assessment of biotic communities. There has been a continuous development of these biological indicators but primarily based on fundamental approaches that date back to the original assessment systems. The indicators used today ignore large parts of what is occurring in the ecosystem and cannot, in most cases, diagnose the cause of degradation with a reasonable precision. There is clearly a need to improve existing assessment systems through new and innovative approaches that, as an example, include ecosystem processes and can be linked more closely to the services that lotic ecosystems provide. This article critically reviews the use of biological indicators in the context of inherent properties of lotic ecosystems and types of degradation, and suggests how assessment could be refined through applying a number of additional approaches to those already used. WIREs Water 2014, 1:513–531. doi: 10.1002/wat2.1040This article is categorized under: Water and Life > Conservation, Management, and Awareness Water and Life > Stresses and Pressures on Ecosystems Science of Water > Water and Environmental Change

Skin conductance rises in preparation and recovery to psychosocial stress and its relationship with impulsivity and testosterone in intimate partner violence perpetrators

Intimate partner violence (IPV) perpetrators were categorized into 2 groups using Gottman et al.'s (1995) typology depending on their skin conductance (SC) reactivity to stress. Overall, type I perpetrators tend to show autonomic underarousal, whereas type II perpetrators present a preparatory hyperreactivity to confront stress. Moreover, impulsivity traits and testosterone (T) levels may modulate SC responses to increase the risk of proneness to violence. In this study, SC response to stress was assessed by comparing IPV perpetrators with non-violent controls while performing a modified version of the Trier Social Stress Test (TSST). Subjects with a history of IPV demonstrated higher non-specific SC responses during the recovery period than the non-violent controls. Nonetheless, there were no differences between groups in the case of mean SC levels. Furthermore, impulsivity and baseline T levels were associated with higher SC level reactivity during a preparation period only in IPV perpetrators, with both relationships being mediated by anger expression. Our results confirm that the IPV perpetrators correspond physiologically to type II and support the validity of SC as a diagnostic indicator for IPV classification. Our findings contribute to the development of effective treatment and prevention programs that could benefit from the use of biological indicators for analyzing the risk of recidivism in IPV perpetrators.

Algal and Cyanobacterial communities in two rivers of the province of San Luis (Argentina) subjected to anthropogenic influence

AIM: The use of biological indicators of pollution has increased in recent years as an alternative to the monitoring of water quality. Phytoplankton community selectively respond to different anthropogenic disturbances, such as water dams and the increase of nutrients coming from city centers, which leads to the eutrophication of the aquatic environment. The objective of this work was to evaluate the composition and the structure of the algal and Cyanobacterial communities in order to prove human influences by the presence of reservoirs with some degree of eutrophication and the impact of urbanization in two rivers at the Bebedero basin in San Luis province (Argentine). METHODS: Four sites were sampled: two of them were placed before dams and villages (V1) and (P1) and two after them (V2) and (P2). Each site was visited in every season of the year: summer, autumn, winter and spring. Qualitative and semi-quantitative phytoplankton samples were taken, and the frequency of occurrence was determined. Variations between pairs of sampling stations were analyzed through the Jaccard similarity and complementarity indices. RESULTS: Ninety two taxa were identified, of which diatoms were the most frequent. The most affected station was P2 with high abundance, less diversity and equitability, whereas the species more tolerant to the presence of organic matter were Melosira varians, Navicula tripunctata, Oscillatoria limosa, Gomphonema parvulum and Coelastrum microporum, and some species of euglenophytas. CONCLUSION: Therefore, the structure and composition of the algal and Cyanobacterial communities allowed us to identify sections more sensitive to human-induced alterations.

A Quality Assurance Project to Track Compliance with Autoclave Maintenance and Use of Biological Indicators in Outpatient Physician Offices

percent). In 2004, a targeted assessment of HCWs compliance with HH was conducted in our facility identifying a similar compliance rate to the nation. In order to improve compliance, the HH Program was created comprising of the Hand Hygiene Compliance Team. Project: Our Program was based on the Institute of Healthcare Improvement (IHI) “How to Guide: Improving Hand Hygiene.” The four IHI components to improve compliance were implemented: 1) education of staff was conducted through employee training and multi-component publicity campaigns, 2) improvement of HH technique using several methods, 3) increase availability of alcoholbased hand rubs(ABHRs) throughout the facility, 4) HH observations performed using Center for Disease Control and Prevention (CDC) guidelines. Results: 1) Education of staff was conducted through orientation, annual training and section specific training. Twomulti-component campaigns were implemented-first one in 2006, and the second in 2008. Campaigns included: HH posters, life size figure of facility leader, HH pamphlets, quarterly HH articles, HH trophy, incentives for patients/staff and HH surveys for the second campaign. Survey results (2009-2011) reveal that staff awareness of the campaign increased with each year and was above 90% and patient awareness was above 80%. 2) Correct techniques for using an ABHR and handwashing were discussed during educational sessions, 2 videotape Presentations, and using fluorescent dye-based training methods. 3) Pocket-size ABHRswere distributed and a survey of the facility was conducted to maximize the availability of ABHR wall units in patient care areas. 4) HH compliance checklist was created for use by trained observers. Targeted areas were surveyedmonthly with a minimum of 30 opportunities for HH observed, immediate feedback given, and compliance rates reported to leadership. Results: 24,840 observations were performed from 2006 to 2011, with the most observations done in 2006 (5,369) and the least in 2011 (2,991). The facility goal was set at 90% compliance rate and was reached in the latter part of 2008.The lowest overall compliance rate was 77% in 2006/2007, and the highest compliance rate was 94% in 2011. Physicians/Respiratory Therapy technicians improved the most.

Response of different benthic indices to diverse human pressures

The interest in benthic indicators for soft-bottom marine communities has dramatically increased after a rather long period of relative stagnation due to the need for new tools to assess the status of marine waters, called for by the Clean Water Act and the Water Framework Directive. Our expertise on benthic communities has permitted us to gather a vast amount of data from diverse water bodies under unpolluted and polluted conditions (e.g., accidental oil spill, sewage, long-term anthropogenic estuarine constraints) in tidal estuaries, harbours, and on the coastal shelf from Atlantic Ocean and Mediterranean Sea. We compared the results of four biotic indices on the various available datasets: Shannon-Wiener H′ diversity, AMBI and BO2A, which divide the species into Ecological Groups, and ITI, which divides the species into trophic groups, and the agreement of Best Professional Judgement (BPJ) on the assessment of ecological conditions. Benthic indicators as “ sentinel species”, which is a particular species that by its presence or its relative abundance warns of possible unbalances in the surrounding environment or distortions in community functions, was also tested. Indicators, BPJ and opportunist sentinel species gave similar ECoQS for the different sampling sites. We discuss the use of Biological Indicators as ‘objective’ or ‘subjective’ alternatives for assessing soft-bottom communities, and propose to employ simple methods such as BPJ and taxonomy sufficiency in such diagnostic approaches.

Recuperação de solos degradados na exploração mineral de cassiterita: biomassa microbiana e atividade da desidrogenase

A avaliação da qualidade ambiental assume grande importância em programas de recuperação de áreas degradadas, razão pela qual se faz necessário o desenvolvimento de sistemas quantitativos, com base em combinação de indicadores que melhor representem as condições de degradação ou recuperação em curso. O presente trabalho utiliza-se de parâmetros biológicos do solo como a biomassa microbiana e a atividade de desidrogenase, além da análise do material vegetal, para verificar a influência do plantio sucessivo de leguminosas em um solo minerado em processo de recuperação. A atividade microbiana foi determinada a partir da quantificação do carbono e o nitrogênio da biomassa microbiana (BMC e BMN respectivamente), da atividade da desidrogenase e da hidrólise do FDA avaliadas em uma área de piso de lavra após um, dois e três anos de plantio consecutivos de leguminosas e de uma área de deposição de rejeito após um ano de plantio de um mistura de leguminosas: feijão guandu, mucuna preta e crotalária juncea, comparados com o solo sob mata e com áreas sem plantio. O uso dos indicadores biológicos: biomassa microbiana e atividade de desidrogenase, e da análise do material vegetal na avaliação das técnicas e estratégias de recuperação adotadas revelaram que o plantio de leguminosas e sua posterior incorporação vêm promovendo alterações graduais positivas no solo degradado, principalmente em relação à BMC em áreas após o plantio consecutivo de três anos de leguminosas.

Use of biological indicators to assess water quality of the Ul River (Portugal)

Diatoms and macroinvertebrates have been extensively used as water quality indicators in Europe for the last two decades. In Portugal, the use of biological indicators to assess water quality in rivers has increased greatly. The aim of this work was to assess the water quality and ecological status of the Ul River in order to evaluate its ability for the establishment of a fluvial beach, using periphytic diatoms and macroinvertebrates as indicators. Four sites were selected along the Ul River. At each site, biological, physical, and chemical parameters were investigated. Epilithic diatoms and macroinvertebrates were sampled. The Specific Polluosensitivity Index and the Biological Diatom Index were applied to diatom data, while for macroinvertebrates, the Iberian Biological Monitoring Working Party (IBMWP) was used. According to the results obtained, it was possible to conclude that up to now, this river does not possess the ideal conditions for the establishment of a fluvial beach. We concluded that epilithic diatoms and macroinvertebrates provided consistent information on water quality assessment and can be used as biological indicators of the water quality in Ul River.

Biological indicators of soil quality in organic farming systems

AbstractThe health of the soil, recognized by its active role in the linked processes of decomposition and nutrient supply, is considered as the foundation of agriculture by the organic farming movement. Nutrient management in organically managed soils is fundamentally different from that of conventional agricultural systems. Crop rotations are designed with regard to maintenance of fertility with a focus on nutrient recycling. Where nutrients are added to the system, inputs are in organic and/or non-synthetic fertilizer sources that are mostly slow release in nature. Hence a greater reliance is placed on soil chemical and biological processes to release nutrients in plant-available forms. In this respect, nutrient availability in organically farmed soils is more dependent upon soil processes than is the case in conventional agriculture. The development and use of biological indicators of soil quality may therefore be more important in organic (and other low input) farming systems. The aim of this paper is to evaluate current evidence for the impact of organic farming systems on soil biological quality and consider the identification of appropriate biological indicators for use by organic farmers and their advisors. Organic farming systems are generally associated with increased biological activity and increased below-ground biodiversity. The main impacts on biological fertility do not result from the systemsper sebut are related to the amount and quality of the soil organic matter pool and disruptions of soil habitat via tillage. Even within the constraints of organic farming practices it is possible for farmers to make changes to management practices which will tend to improve soil biological quality. It is, however, by no means clear that distinct indicators of soil biological quality are needed for organic farming systems. It is important not only to identify the most appropriate indicators but also to ensure that farmers and land managers can understand and relate to them to support on-farm management decisions.

Toxicity of Polycyclic Aromatic Hydrocarbons to the Nematode Caenorhabditis elegans

The presence of polycyclic aromatic hydrocarbons (PAHs) in the environment has attracted much concern owing to their mutagenic and carcinogenic properties. Regulatory authorities have favored the use of biological indicators as an essential means of assessing potential toxicity of environmental pollutants. This study aimed to assess the toxicity of acenaphthene, phenanthrene, anthracene, fluoranthene, pyrene, and benzo[a]pyrene to Caenorhabditis elegans by measuring LC50 and EC50 values for growth and reproduction. The exposure to all chemicals was carried out in aqueous medium. All PAHs showed a low acute toxicity to C. elegans. There was no significant mortality in C. elegans after 24 h of exposure at PAH concentrations within (and indeed above) their respective solubility limits. Prolonged exposure (72 h) at high concentrations for acenaphthene (70,573 μg/L), phenanthrene (3758 μg/L), anthracene (1600 μg/L), fluoranthene (1955 μg/L), pyrene (1653 μg/L), and benzo[a]pyrene (80 μg/L) produced mortality. Results also showed that reproduction and growth were much more sensitive parameters of adverse response than lethality, and consequently may be more useful in assessing PAH toxicity using C. elegans. In comparison with previous studies, C. elegans was found to be approximately 2-fold less sensitive to acenaphthene, 5-fold less sensitive to phenanthrene, and 20-fold less sensitive to fluoranthene than Daphnia magna. However, the 48-h LC50 for benzo[a]pyrene (174 μg/L) reported in the present study with C. elegans was similar to that reported elsewhere for Daphnia magna (200 μg/L). Although C. elegans indicated greater sensitivity to benzo[a]pyrene than Artemia salina (174 μg/L vs. 10000 μg/L), the organism showed less sensitivity to pyrene (8 μg/L vs. 2418 μg/L), fluoranthene (40 μg/L vs. 2719 μg/L), and phenanthrene (677 μg/L vs. 4772 μg/L) than Artemia salina. Caenorhabditis elegans, while not the most sensitive of species for PAH toxicity assessment, may still hold applicability in screening of contaminated soils and sediments.

Is Ocypode quadrata (Fabricius, 1787) a useful tool for exposed sandy beaches management in Bahia State (Northeast Brazil)?

Universidade Federal da Bahia - Instituto de Geociencias landim@ufba.br Despite the existing proposals for sustainable use of the Brazilian coast, there are few mechanisms for quantification and qualification of anthropogenic impacts. For instance, the Projeto Orla (MMA, 2006) defines typologies of coastline classification, taking into account aspects of the landscape such as originality, human population density and levels of occupation. Nevertheless, the effects of urbanization on resident biota are not considered in this classification. Furthermore, there is a need for studies to validate the use of biological indicators that take into account the spatial and temporal variation of the biota, so as to arrive at a complete assessment of the urbanization impacts on exposed sandy beach. The genus