The article describes that many countries throughout the world share similar concerns about sediment management. Scientists in several countries have developed a variety of methods for evaluating the de-gree to which sediment-associated chemicals might adversely affect aquatic organisms. The results of ex-periment where consensus approach was used for sediments assessment of Dnieper and Buh estuary and Danube estuary in Ukraine are presented in article

Goncharova, M. T.

Martynova, Y. S.

English

Наукові журнали Національного Авіаційного Університету

Наука і молодь. Прикладна серія  131UDC 504.454 (045) Martynova Y. S., Goncharova M. T. National Aviation University, Kyiv USE OF SEDIMENT QUALITY GUIDELINES FOR THE ASSESSMENT  OF CONTAMINATED SEDIMENTS OF UKRAINIAN ESTUARIES The article describes that many countries throughout the world share similar concerns about sediment management. Scientists in several countries have developed a variety of methods for evaluating the de-gree to which sediment-associated chemicals might adversely affect aquatic organisms. The results of ex-periment where consensus approach was used for sediments assessment of Dnieper and Buh estuary and Danube estuary in Ukraine are presented in article. Environmental scientists, engineers and regula-tory authorities throughout the world have devoted considerable resources to assessment, management, and remediation of chemical contaminants in sedi-ments. Sediment quality has become a serious and potentially costly economical and ecological issue for navigation dredging projects, waterway restora-tion programs, recreational and commercial fisheries management, water quality protection, and natural resources restoration. Numerous scientific and engineering studies have shown that addressing contaminated sediments is a complex undertaking. Complexity arises from the great variability in the physical and biogeo-chemical characteristics of sediments; human and ecological receptors; and the cultural, social and economic values associated with different freshwa-ter, estuarine, and marine environments. In response to the increasing demands from soci-ety for greater environmental protection of aquatic re-sources and the restoration of impaired or degraded rivers and estuaries, scientists in several countries have developed a variety of methods for evaluating the degree to which sediment-associated chemicals might adversely affect aquatic organisms. While some methods have focused on the derivation of nu-meric chemically based sediment concentration lim-its, other methods have focused on less-specific narra-tive statements or bench-marks that frame acceptable and potentially unacceptable sediment quality. The interaction of benthic organisms with sedi-ments environment is complex. The demand for tools to aid decision making is ongoing and intense, and has led to the development of SQGs by a variety of methods. Existing SQGs can be categorized into 3 groups, according to their derivation: 1) empirically based (or “co-occurrence”) guidelines; 2) mechanistically based (e.g., equilibrium-partitioning [EqP]) guidelines; 3) “consensus-based” guidelines. SQGs for assessing sediment quality relative to the potential for adverse effects on sediment-dwelling organisms have been derived using both  mechanistic approaches:  the equilibrium partitioning (EqP) approach;  empirical approaches:  screening-level concentration (SLC) ap-proach;  effects range approach (ERA);  effects level approach (ELA);  apparent effect threshold (AET) approach;  consensus-based approach;  logistic regression modeling approach. These SQGs have been used to interpret histori-cal data, identify potential problem chemicals or ar-eas at a site, design monitoring programs, classify hot spots and rank sites, and make decisions for more detailed studies. Empirical guidelines are derived from databases of sediment chemistry (concentrations of specific sediment contaminants) and observed biological ef-fects (e.g., those derived from sediment toxicity tests and benthic community information). These data are arrayed on a continuum or increasing chemical con-centration. Various analysis approaches are then ap-plied to relate chemical concentrations to the fre-quency of biological effects.  In contrast, mechanistic guidelines are derived from a theoretical understanding of the factors that govern bioavailability of sediment contaminants, and known relationships between chemical exposure or uptake and toxicity. Existing mechanistic SQGs all have their roots in EqP theory, where concentra-tions of chemical in sediment are related to the cor-responding concentrations in pore water.  Consensus-based guidelines aggregate guide-lines developed using different methods, and gener-ate new SQGs from the central tendencies of guide-lines with different intents (e.g., threshold effect, median effect). Екологічна безпека  132The mechanically based sediment quality guide-lines (SQGs) have been developed and tested using laboratory spiked sediments and compared to toxic-ity tests by using field-collected sediments. The em-pirically based SQGs have typically been developed using large databases with matching measures of sediment chemistry and toxicity from field-collected samples. These databases also have been used to evaluate the ability of SQGs to predict sediments to be either toxic or nontoxic in laboratory tests or in benthic community assessments in a variety of freshwater, estuarine, and marine environments. Generally, the results of analysis conducted with these databases in conjunction with field validation studies involving contaminated sediments suggest that some effects-based SQGs can provide reason-able predictions, with associated error rates and un-certainties, for the potential for acute effects or no effects on benthic organisms. Most industrialized countries have to deal with the regulation and management of contaminants in sediments and dredged materials in their waterways. As a consequence, a variety of approaches has been or is being developed. In many cases, sediment qual-ity guidelines form part of these approaches. Many countries throughout the world share simi-lar concerns about sediment management.  Two distinct approaches to SQGs have been adopted in countries outside of North America. Par-ticularly in Europe, the application of guidelines based on reference conditions has been widely prac-ticed. In this context, the reference condition can be defined either as “background concentrations” or as an array of chemical and biological parameters measured at reference sites. This approach has, at least for some time, hampered the application of empirical or mechanistic SQGs that have achieved wide use in North America in recent years. The reference condition approach is, or was, used by Flanders in Belgium, France, Germany, and Italy. However, several of these countries have be-gun to develop effects-based SQGs, which are or will be used instead of, or sometimes in combination with, the reference condition approach. Australia and New Zealand have recently revised their guidelines for fresh and marine water quality and have included, for the first time, a consideration of sediment quality. Australian guidelines for ocean disposal of dredged materials have also been devel-oped recently. Both use a common approach to SQG development: an ecotoxicological effects database. Faced with a paucity of local sediment effects data, the effects range low (ERL) values derived from the North American database were used as the basis for interim Australian and New Zealand guidelines. The application of the Australian and New Zea-land SQGs for both in situ and dredged sediments follows a tiered system, in the form of a risk-based decision tree that progresses through a hierarchy of measurements that get closer to a bioavailable frac-tion, in the same manner as the tiered system has adopted for water quality. For metals, the use of a dilute acid-soluble metals fraction was seen as more useful than a total measurement, although (total con-centrations are used in the North American guide-lines from which the tiered system was adapted). The weak link in the decision tree at this stage is the assessment of impacts by toxicity testing. Often we are dealing with multiple toxicants, where the test species may be especially sensitive to only some classes of toxicants. It is important that tests encom-pass the range of uptake routes and include sensitive species. The expansion of the risk-based approach to include ecological impacts as well as bioaccumu-larion is a logical extension of the framework, along the lines of a WOE approach. This inclusion of eco-logical impacts is already addressed explicitly in the Australian and New Zealand guidelines that recom-mend a combination of biological (biodiversity) and chemical assessments. The adoption of this integra-tion of chemistry and biology for sediments is equally desirable. In Belgium, sediment quality was assessed on the basis of comparisons with reference sites. Ini-tially, 5 locations were chosen as reference sites. Previous ecological studies showed that these sites were in relatively undisturbed areas with a high eco-logical quality. The chemistry at these sites was con-sidered close to reference values used in other Euro-pean countries. Guidelines for dredged material are based on guidelines for the reuse on contaminated soil and differ from the reference values. Walloon and Brussels do not have SQGs yet. Sediment quality assessment in Belgium is based on a triad approach. An equal weight is assigned to each of the 3 measurements. The underlying princi-ple of the classification of sediment quality rests on the comparison with a reference condition. This means that, for each type of measurement (physico-chemical, toxicity tests, invertebrate communities), a desirable reference condition has first to be defined. In France sediment quality assessments are un-dertaken for 2 purposes: 1) the monitoring of water bodies sometimes followed by more detailed diag-nostic at impaired locations, and 2) the management of dredged materials. Sediment quality monitoring Наука і молодь. Прикладна серія  133was until recently based on analyses of priority pol-lutants and application of numerical SQGs. The use of toxicity tests is now seriously envisaged, follow-ing several demonstrative studies. The Federal Republic of Germany does not yet have common national regulations for the manage-ment of contaminated sediments. The management of dredged materials in coastal areas in Germany is driven by the reference values. Two action levels have been defined for coastal sediments. The first reference value is based on prevailing contaminant concentrations in the Wadden Sea (part of the North Sea, mainly along German coast) between 1982 and 1992. The second level is defined as 5× the refer-ence value for metals and 3× this value for organic compounds. Thus, they are derived by convention and are not effect based. Sediment quality issues for Hong Kong were largely focused on marine dredged sediments. These were first managed according to 3 classes of con-tamination. The criteria delineating these classes were considered conservative and were too close to one another, given measurement uncertainty. It was recommended the development of interim sediment quality values (ISQVs), on the basis of published papers combined with the collection of site-specific information (e.g., through biological testing). Thus 2 sets of ISQVs were determined, that is, an ISQV-low, below which adverse effects were unlikely, and an ISQV-high, above which severe adverse effects were very likely. Only the ISQV-low was proposed for decision-making. Implementation of the ISQV-high values would follow the incorporation of re-gional data (toxicity test results and chemical con-centrations). In Italy, there are no national SQGs, although some work has been undertaken on the development of guidelines for freshwater sediments, dredged ma-terial, and sediments for marine disposal. Environ-mental quality is evaluated on the basis of ecological and chemical status of a given water body compared to a reference one, and water bodies are classified in 5 classes of quality. The ecological status is assessed on the basis of the diversity and abundance of cer-tain types of living organisms and morphological conditions, while the chemical status is based on the occurrence and concentrations of dangerous sub-stances (priority list) in compliance with environ-mental quality standards (EQSs). The list of priority substances was selected from other lists issued by organizations such as the US Environmental Protec-tion Agency (USEPA), the United Nations Envi-ronment Programme (UNEP), and the European Commission. Other hydrological and morphological variables are also included in the monitoring re-quirements because of the potential impacts of hu-man activity and water uses and the affinities of con-taminants for sediments. It is recommended, in case of further investigations, that toxic effects be as-sessed using a multispecies approach, short- and long-term toxicity tests on sediment extracts, whole sediments, or pore water with test organisms. In Netherlands the approach adopted for sedi-ment quality consisted of calculating quality criteria for water and sediment from existing ecotoxicity test data (usually concentrations of toxicants in water) or product standards (in food) based on EqP theory. In theory, alternative approaches might be applied for the derivation of SQGs, either by applying assess-ment factors to spiked tests results or by statistical extrapolation. Nevertheless, the criteria should then be harmonized among water and sediment compart-ments by applying EqP theory. In the Netherlands, most of the published SQGs are obtained by EqP. Numerical effects-based sediment quality guide-lines (SQGs) have been developed by federal, pro-vincial, or state agencies in the United States (US), Canada, Australia, Italy, the Netherlands, and Hong Kong. The approaches that have been selected by different jurisdictions for different management situations depend on the receptors to be protected (e.g., sediment-dwelling organisms, wildlife, or hu-mans), the degree of protection that is to be afforded, the geographic area to which the SQGs are intended to apply, and their intended uses.  In Ukraine there are no adopted standards for sediments quality assessment. For assessment of sediment quality in Ukraine there can be used stan-dards adopted in North America, for example. We conducted the assessment of two water eco-systems – Dnieper and Buh estuaries and water ob-jects of Danube estuary. The content of many toxi-cants was researched (heavy metals, PAH, PCBs, pesticides, etc.) in sediments of these water objects. We applied consensus approach and calculated threshold effect concentration (TEC) of toxicants in each water object. TEC was proposed by Environ-mental Protection Agency (EPA) in USA and were used in researches because of absence of norms in our country. The data are presented as correlation of toxicants content in sediments with TEC. The experiments were conducted on whole tests with test organism Chironomus riparius and on wa-ter elutriates with test organisms Daphnia Magna. We observed the difference between researched water objects in character of correlation between Екологічна безпека  134levels of sediments pollution, their structure, and de-velopment of toxic effect on test organisms. For Dnieper and Buh estuary a high correlation between level of pollution and toxic effect in whole sediment tests for both Chironomus riparius and Daphnia Magna was observed. At the same time, for Danube estuary correlation was observed only in experi-ments on water elutriates with Daphnia Magna.  R2 = 0,72070,05,010,015,020,025,030,035,040,045,00 20 40 60 80 100Sum TECSurvival, %  а R2 = 0,05640,010,020,030,040,050,060,00 20 40 60 80 100Sum TECSurvival, %  b Pic. 1. Dependence of toxic effect from the content of toxic substances (whole tests): a – Dnieper and Buh estuary; b – Danube estuary Obtained results give us the opportunity to conclude that at standardization of polluting substances content in sediments it is necessary to take into account regional specific of each researched water object that are different by hydrological, hydrochemical regimes, and genesis of sediments. Such approach is coordinated with Water Framework Directive of EU, that establishes main principles of water resources management. One of the main principles stated by Water Framework Directive of EU is integrated river basin model of water resources management.  Scientific supervisor – Krot Y. G., assistant professor 

USE OF SEDIMENT QUALITY GUIDELINES FOR THE ASSESSMENT OF CONTAMINATED SEDIMENTS OF UKRAINIAN ESTUARIES

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USE OF SEDIMENT QUALITY GUIDELINES FOR THE ASSESSMENT OF CONTAMINATED SEDIMENTS OF UKRAINIAN ESTUARIES

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Наукові журнали Національного Авіаційного Університету

USE OF SEDIMENT QUALITY GUIDELINES FOR THE ASSESSMENT OF CONTAMINATED SEDIMENTS OF UKRAINIAN ESTUARIES

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Наукові журнали Національного Авіаційного Університету

Наукові журнали Національного Авіаційного Університету