[pt] Os efluentes líquidos contaminados com metais pesados é uma ameaça ambiental, os íons metálicos tóxicos encontram-se dissolvidos, atingindo eventualmente o topo da cadeia alimentar e assim, tornando-se um fator de risco para a saúde humana e ambiente. Diversos métodos de tratamento de efluentes como precipitação química, coagulação, floculação, flotação, troca iônica e filtração são empregados para remoção dos metais pesados. Entretanto, estes possuem algumas desvantagens quando empregados para tratamento de grandes volumes de efluentes líquidos com baixas concentrações de metais. Neste trabalho foi avaliada a cepa bacteriana Rhodococcus opacus como um potencial biossorvente para a remoção de mercúrio de soluções aquosas através de biossorção. O valor de pH adequado para a biossorção foi em torno de 5 para o metal. Os dados correspondentes à capacidade de captação do Rhodococcus opacus em função da concentração do mercúrio foi bem ajustada ao modelo de Freundlich. A capacidade de captação máxima obtida foi de 37,9 mg.g-1 para o mercúrio, equivalente a uma remoção de 73,42 %. A cinética de biossorção para o mercúrio foi modelada pela equação de pseudo-segunda ordem. Foram avaliadas também as propriedades superficiais dos microorganismos antes e após a interação dos metais para poder determinar os possíveis mecanismos implicados na biossorção mediante medições de espectroscopia de infravermelho. Os resultados apresentados mostram que o Rhodococcus opacus apresenta características adequadas no que tange a flotação biossortiva para remoção de metais. / [en] Heavy metals presence in wastewaters is a common environmental threat, since these toxic metal ions are dissolved, eventually reaching the top of the food chain and thus become a risk factor to human health and the environment. Mercury is considered a pollutant of high risk been regulated by USEPA (United States Environmental Protection Agency). The concern regarding pollution by mercury emerges of the problems to health caused for exposition to methyl mercury found in the aquatic water and foods in normal conditions. Several methods of effluent treatment like chemical precipitation, coagulation, flocculation, flotation, ion exchange, filtration are used to remove heavy metals. These methods have some drawbacks when used for treating large volumes of wastewater with low concentration of the metal. In this study we evaluated the bacterial strain Rhodococcus opacus as a potential biosorbent for mercury removal from aqueous solutions through biosorption. The pH value suitable for the biosorption of the metal was around 5. The data corresponding to the uptake capacity of Rhodococcus opacus depending on the concentration of mercury was well adjusted to the Freundlich model. The maximum uptake capacity was about: 37.9 mg.g-1 for mercury equivalent to a removal of 73.42%. The kinetics of mercury biosorption was representated by a equation of pseudo-second order. We also evaluated the surface characteristics of the microorganism before and after the interaction of metals in order to determine the possible mechanisms involved in biosorption by measurements of infrared spectroscopy. The results demonstrated that Rhodococcus opacus shows good performance as biosorbent for bioaccumulation of Hg (II).

A comprehensive method for the analysis of 11 target pharmaceuticals representing multiple therapeutic classes was developed for biological tissues (fish) and water. Water samples were extracted using solid phase extraction (SPE), while fish tissue homogenates were extracted using accelerated solvent extraction (ASE) followed by mixed-mode cation exchange SPE cleanup and analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS). Among the 11 target pharmaceuticals analyzed, trimethoprim, caffeine, sulfamethoxazole, diphenhydramine, diltiazem, carbamazepine, erythromycin and fluoxetine were consistently detected in reclaimed water. On the other hand, caffeine, diphenhydramine and carbamazepine were consistently detected in fish and surface water samples. In order to understand the uptake and depuration of pharmaceuticals as well as bioconcentration factors (BCFs) under the worst-case conditions, mosquito fish were exposed to reclaimed water under static-renewal for 7 days, followed by a 14-day depuration phase in clean water. Characterization of the exposure media revealed the presence of 26 pharmaceuticals while 5 pharmaceuticals including caffeine, diphenhydramine, diltiazem, carbamazepine, and ibuprofen were present in the organisms as early as 5 h from the start of the exposure. Liquid chromatography ultra-high resolution Orbitrap mass spectrometry was explored as a tool to identify and quantify phase II pharmaceutical metabolites in reclaimed water. The resulting data confirmed the presence of acetyl-sulfamethoxazole and sulfamethoxazole glucuronide in reclaimed water. To my knowledge, this is the first known report of sulfamethoxazole glucuronide surviving intact through wastewater treatment plants and occurring in environmental water samples. Finally, five bioaccumulative pharmaceuticals including caffeine, carbamazepine, diltiazem, diphenhydramine and ibuprofen detected in reclaimed water were investigated regarding the acute and chronic risks to aquatic organisms. The results indicated a low potential risk of carbamazepine even under the worst case exposure scenario. Given the dilution factors that affect environmental releases, the risk of exposure to carbamazepine will be even more reduced.

O objetivo geral do trabalho foi avaliar a distribuição e os efeitos tóxicos dos metais Cr e Cu sobre os ecossistemas aquáticos lênticos, incluindo seus componentes bióticos e abióticos, utilizando-se sistemas com diferentes níveis de complexidade e organização. Os sistemas utilizados na avaliação da toxicidade de Cr e Cu foram: a) testes uniespecíficos com Selenastrum capricornutum (microalga), Daphnia similis e Ceriodaphnia dubia (Cladocera), Chironomus xanthus (Diptera, Chironomidae), Oreochromis niloticus (peixe) e Pistia stratiotes (macrófita); b) experimentos em microcosmos (testes multiespecíficos) com as comunidades naturais da represa do Lobo; c) experimentos em mesocosmos, contando com água, sedimento, plâncton, bentos, peixes e macrófitas naturais da represa do Lobo. Nos testes de toxicidade todas as espécies foram mais sensíveis ao Cu que ao Cr, e a sequência de sensibilidade foi D. similis> C. dubia> S. capricornutum> C. xanthus > P. stratiotes > O. niloticus. Nos experimentos em microcosmos e mesocosmos, as concentrações-teste foram definidas como o valor máximo permitido pela Resolução nº 20/1986 do CONAMA para Cr6+ e Cu2+ para corpos dágua Classe 2 (50 µg.L-1 e 20 µg.L-1, respectivamente). Em todos os experimentos a concentração de clorofila foi reduzida significativamente após a adição dos metais. Os efeitos sobre a densidade e riqueza de espécies das comunidades zooplanctônicas foram mais severos para o Cr que para o Cu; porém Cladocera foi mais sensível ao Cu. Cromo provocou uma maior inibição na produção primária em abril de 2002, enquanto que em novembro/dezembro de 2002 a produção primária sofreu maior decréscimo após a adição de Cu. Ambos os metais estudados apresentaram efeitos significativos sobre um grande número de variáveis da água, como oxigênio dissolvido, amônio, distribuição das formas fosfatadas, clorofila e material em suspensão, sendo os efeitos do Cr mais severos que os do Cu, em relação ao número de variáveis afetadas e ao tempo de restauração do sistema. Os sedimentos não apresentaram alterações após a adição de metais. Foi observada a ocorrência de bioacumulação de Cr e Cu pelo plâncton, bentos, macrófitas e peixes. A toxicidade dos metais estudados foi reduzida após a inclusão de peixes e macrófitas, principalmente para Cu. Apesar das concentrações de Cr e Cu relativamente baixas empregadas, os metais provocaram efeitos nos compartimentos bióticos e abióticos do sistema. Os resultados obtidos no presente trabalho podem ser úteis como subsídio para a avaliação dos valores máximos permitidos pela Resolução nº 20/1986 do CONAMA para os metais estudados. / The general aim of this work was to evaluate the distribution and the toxic effects of the metals Cr and Cu on lenthic aquatic ecosystems, using systems of different complexity and organization levels. The systems used for Cr and Cu toxicity evaluations were: a) single-specific tests with Selenastrum capricornutum (microalgae), Daphnia similis e Ceriodaphnia dubia (Cladocera), Chironomus xanthus (Diptera, Chironomidae), Oreochromis niloticus (fish) and Pistia stratiotes (macrophyte); b) microcosms experiments (multi- specific tests) with the Lobos reservoir natural communities; c) mesocosms experiments, with natural water, sediment, plankton, benthics, fishes and macrophytes from Lobos reservoir. In the toxicity tests, all the species were more sensitive to Cu than to Cr, and the sensitiviness sequence was D. similis> C. dubia> S. capricornutum> C. xanthus > P. stratiotes > O. niloticus. In the microcosms and mesocosms experiments, the test-concentrations were the maximum value allowed by the CONAMA Resolution nº 20/1986 to Cr6+ and Cu2+ to Class 2 water bodies (50 µg.L-1 and 20 µg.L-1, respectively). In all experiments the chlorophyll concentration was significantly reduced after the metal addition. The effects on the Zooplankton density and richness were stronger to Cr than to Cu; however Cladocera was more sensitive to Cu. Chromium caused higher inhibition in primary production in April/ 2002, but in November/ December 2002 the primary production suffered higher inhibition by Cu addition. Both studied metals showed significant effects on several water variables, as dissolved oxygen, ammonium, phosphate forms distribution, chlorophyll and suspended material, being the Cr effects stronger than the Cu effects, in relation to the number of affected variables and the system restoration time. The sediments didnt show alterations after the metal addition. Chromium and Cu bioaccumulation was observed by plankton, benthic invertebrates, macrophytes and fishes. The toxicity of the studied metals was reduced by the fish and macrophyte inclusion, mainly to Cu. Although the concentration of Cr and Cu were low, toxic effects were observed on both biotic and abiotic system compartments. The results obtained in this work may be useful as subsidy to evaluation of the maximum value allowed by the CONAMA Resolution nº 20/1986 to the studied metals.

O objetivo geral do trabalho foi avaliar a distribuição e os efeitos tóxicos dos metais Cr e Cu sobre os ecossistemas aquáticos lênticos, incluindo seus componentes bióticos e abióticos, utilizando-se sistemas com diferentes níveis de complexidade e organização. Os sistemas utilizados na avaliação da toxicidade de Cr e Cu foram: a) testes uniespecíficos com Selenastrum capricornutum (microalga), Daphnia similis e Ceriodaphnia dubia (Cladocera), Chironomus xanthus (Diptera, Chironomidae), Oreochromis niloticus (peixe) e Pistia stratiotes (macrófita); b) experimentos em microcosmos (testes multiespecíficos) com as comunidades naturais da represa do Lobo; c) experimentos em mesocosmos, contando com água, sedimento, plâncton, bentos, peixes e macrófitas naturais da represa do Lobo. Nos testes de toxicidade todas as espécies foram mais sensíveis ao Cu que ao Cr, e a sequência de sensibilidade foi D. similis> C. dubia> S. capricornutum> C. xanthus > P. stratiotes > O. niloticus. Nos experimentos em microcosmos e mesocosmos, as concentrações-teste foram definidas como o valor máximo permitido pela Resolução nº 20/1986 do CONAMA para Cr6+ e Cu2+ para corpos dágua Classe 2 (50 µg.L-1 e 20 µg.L-1, respectivamente). Em todos os experimentos a concentração de clorofila foi reduzida significativamente após a adição dos metais. Os efeitos sobre a densidade e riqueza de espécies das comunidades zooplanctônicas foram mais severos para o Cr que para o Cu; porém Cladocera foi mais sensível ao Cu. Cromo provocou uma maior inibição na produção primária em abril de 2002, enquanto que em novembro/dezembro de 2002 a produção primária sofreu maior decréscimo após a adição de Cu. Ambos os metais estudados apresentaram efeitos significativos sobre um grande número de variáveis da água, como oxigênio dissolvido, amônio, distribuição das formas fosfatadas, clorofila e material em suspensão, sendo os efeitos do Cr mais severos que os do Cu, em relação ao número de variáveis afetadas e ao tempo de restauração do sistema. Os sedimentos não apresentaram alterações após a adição de metais. Foi observada a ocorrência de bioacumulação de Cr e Cu pelo plâncton, bentos, macrófitas e peixes. A toxicidade dos metais estudados foi reduzida após a inclusão de peixes e macrófitas, principalmente para Cu. Apesar das concentrações de Cr e Cu relativamente baixas empregadas, os metais provocaram efeitos nos compartimentos bióticos e abióticos do sistema. Os resultados obtidos no presente trabalho podem ser úteis como subsídio para a avaliação dos valores máximos permitidos pela Resolução nº 20/1986 do CONAMA para os metais estudados. / The general aim of this work was to evaluate the distribution and the toxic effects of the metals Cr and Cu on lenthic aquatic ecosystems, using systems of different complexity and organization levels. The systems used for Cr and Cu toxicity evaluations were: a) single-specific tests with Selenastrum capricornutum (microalgae), Daphnia similis e Ceriodaphnia dubia (Cladocera), Chironomus xanthus (Diptera, Chironomidae), Oreochromis niloticus (fish) and Pistia stratiotes (macrophyte); b) microcosms experiments (multi- specific tests) with the Lobos reservoir natural communities; c) mesocosms experiments, with natural water, sediment, plankton, benthics, fishes and macrophytes from Lobos reservoir. In the toxicity tests, all the species were more sensitive to Cu than to Cr, and the sensitiviness sequence was D. similis> C. dubia> S. capricornutum> C. xanthus > P. stratiotes > O. niloticus. In the microcosms and mesocosms experiments, the test-concentrations were the maximum value allowed by the CONAMA Resolution nº 20/1986 to Cr6+ and Cu2+ to Class 2 water bodies (50 µg.L-1 and 20 µg.L-1, respectively). In all experiments the chlorophyll concentration was significantly reduced after the metal addition. The effects on the Zooplankton density and richness were stronger to Cr than to Cu; however Cladocera was more sensitive to Cu. Chromium caused higher inhibition in primary production in April/ 2002, but in November/ December 2002 the primary production suffered higher inhibition by Cu addition. Both studied metals showed significant effects on several water variables, as dissolved oxygen, ammonium, phosphate forms distribution, chlorophyll and suspended material, being the Cr effects stronger than the Cu effects, in relation to the number of affected variables and the system restoration time. The sediments didnt show alterations after the metal addition. Chromium and Cu bioaccumulation was observed by plankton, benthic invertebrates, macrophytes and fishes. The toxicity of the studied metals was reduced by the fish and macrophyte inclusion, mainly to Cu. Although the concentration of Cr and Cu were low, toxic effects were observed on both biotic and abiotic system compartments. The results obtained in this work may be useful as subsidy to evaluation of the maximum value allowed by the CONAMA Resolution nº 20/1986 to the studied metals.

No description available.

Philosophiae Doctor - PhD / The increasing evidence of chemicals of emerging concern (CECs) in water bodies is causing major concern around the world because of their toxicological effects upon humans and aquatic organisms. The release of wastewater to the aquatic environment is most likely to introduce some trace levels of organic contaminants, some of which may be toxic, carcinogenic, or endocrine disruptors, as well as, persistent in the environment. These compounds are often persistent but not regularly monitored because they are mostly still excluded from environmental legislation. Their fate and persistence in the environment are not well understood. / 2022-02-24

Pyrethroid insecticides applied on crops and in urban areas are being found in aquatic ecosystems due to natural processes, such as run-off. Although highly toxic to invertebrates and fish, populations of Hyalella azteca have become resistant to some of these compounds, which pose risks to not only their populations, but higher trophic level populations via bioaccumulation (in this thesis, the Inland silverside (Menidia beryllina)). Concurrently, the impact of global climate change (GCC) is impacting environmental water parameters, such as temperature and salinity. The objective of this thesis was to analyze the relationship between varying water parameters due to GCC on the fate of permethrin (a type of pyrethroid) in resistant H. azteca (by measuring toxicokinetic rates) and in M. beryllina (by measuring bioaccumulation after consuming permethrin-dosed resistant H. azteca). Permethrin bioconcentration testing used two distinct populations (Mosher Slough and Escondido Creek) of pyrethroid-resistant H. azteca and showed that temperature and salinity affected toxicokinetic rates. Statistical differences in metabolite formation rates (km) across temperatures were found between and within populations. Salinity also exhibited statistical differences in the elimination of parent compound (kep). No statistically significant differences in uptake rates (ku) were found for either population. In the M. beryllina testing, the ability for the fish to bioaccumulate permethrin via a dietary route of exposure was confirmed, contradicting previous findings. Statistically significant bioaccumulation was found across salinities, whereas no statistically significant temperature effects were observed. With the predicted increased use of pyrethroids over the course of the next century, the emergence of resistant populations of H. azteca may increase, simultaneously increasing the risk for bioaccumulation by higher trophic species. With rates of biotransformation in H. azteca affected by changing water parameters due to GCC change, the ratio of parent and metabolite compound transferred to fish will also be altered. Pyrethroid metabolites in fish act as endocrine disruptors rather than inhibit nerve function like the parent compound, which can significantly affect fish development. Overall, this thesis demonstrates important potential effects of GCC on the rates and biological transfer of pyrethroids by aquatic species, and the potential combined effects of these multiple stressors on two trophic levels of aquatic organisms.

Polycyclic aromatic compounds (PACs) are a group of chemicals encompassing thousands of different aromatic, alkyl aromatic and heterocyclic hydrocarbons (i.e.- containing N, S, or O- atoms); 16 of which have been designated as priority pollutants due to their toxicity and prevalence. Several studies have highlighted increases in the concentrations of C1-C4 alkylated PACs and heterocyclic aromatic hydrocarbons such as dibenzothiophenes in the atmosphere, water, soil and sediments, plants, wildlife and fish in the Athabasca Oil Sands Region (AOSR). Although there has been considerable research attention related to the toxic, carcinogenic and mutagenic properties of PACs, there is an increasing awareness that these chemicals may also have profound endocrine disrupting properties in wildlife. North American river otter (Lontra canadensis) are good indicators of ecosystem health due to their ecology and sensitivity to environmental pollutants. In this thesis, we first demonstrated the utility of adopting paleotoxicological frameworks in defining environmental baseline levels of PACs and likely biological effects from exposure to these complex environmental mixtures. These methods allowed us to reconstruct historical PAC deposition patterns to impacted areas while simultaneously determining likely biological effects such as endocrine disruption. Next, we showed how PACs exhibited trophic dilution in a Boreal food chain dominated by river otters. Snails, prey and predator fish, as well as river otters were collected from four main study areas in the AOSR in northeastern Alberta, Canada. Bioaccumulation factors such as biota-sediment accumulation factors (BSAF) and trophic magnification factors (TMF) were used to evaluate the partitioning behavior of PACs in the environment and subsequent risks to biota. Our results revealed localized enrichment of certain PACs and subsequent metabolism in higher order vertebrates. Finally, we successfully combined ecotoxicological and physiological analyses paired with population genetic estimates to investigate endocrine disruption and population-level responses to exposure to PACs. River otters are known for their habitual use of latrine sites. Latrine sites represent a unique opportunity for biomonitoring programs to study river otters using indirect sampling methods. In this thesis, PACs were characterized and evaluated in sediment, lower and higher trophic biota with demonstrated impacts on endocrine processes and river otter population health. Effects-based assessments such as the ones presented in this thesis are more powerful for environmental monitoring programs than stressor-based assessment methods (such as describing presence/absence or levels of contaminants) as they provide greater biological context to monitoring data. In turn, these are helpful in selecting triggers for environmental effects monitoring or adaptive management programs.

No description available.

Sediments can act as both reservoir and source of legacy organic contaminants such as polychlorinated biphenyls (PCBs). Due to their chemical stability and ubiquity, these contaminants remain as model class of compounds in the field of sediment contamination. Whole sediment and organism concentrations have been often used as exposure metrics for ecological risk assessments. However, whole sediment concentrations often overestimate the potential for exposure to contaminants; while organism concentrations based on bioassay provide a better estimate of exposure, bioassays can also be labor intense, time consuming and expensive. Alternatively, accessiblity-based techniques such as Tenax extractions have been gaining ground, in the last few decades, as a rapid, reliable, and cost-effective approach to estimate exposure to organic contaminants from sediments. Tenax extractions measure the bioaccessible fraction of the contaminant that desorbes from sediment. Despite the simplicity, accuracy and robustness of the Tenax technique to estimate bioaccessibility of organic contaminants, there are still some remaining questions regarding the methodological standardization, and the applicability of the technique in sediments containing diverse carbonaceous sorbents associated adsorption/desorption of the contaminant. Therefore, the chapters of this dissertation were designed to address these questions. To this end, PCBs were chosen as a model compound class to represent a wide range of physicochemical properties of persistent organic contaminants, and because these compounds remain a worldwide legacy contamination problem. The dissertation goals were to: determine the best operational conditions for Tenax technique (Chapter 2); monitor the changes in bioaccessibility of field-collected sediments with different holding time conditions (Chapter 3); examine the effects of the type and quantity of organic carbon on bioaccessibility (Chapter 4); and evaluate the applicability of the Tenax technique to assess remediation success in contaminated marine sediments (Chapter 5). To address the methodological standardization of the Tenax technique, the operational parameters of solvent extract volume, Tenax sorption rate from water, and Tenax:OC (Tenax:Organic Carbon) ratios were investigated in Chapter 2. The highest efficiency of extraction of sorbed PCBs from Tenax resulted from using a 10 mL per each solvent wash during Tenax extraction procedure. For the Tenax sorption, it was found that 0.01 g of Tenax cleared PCB in 40 mL of water in 30 min, thus it would clear the water 48 times in 24 h. When this is extrapolated to the 0.5 of Tenax, typical amount used, it was found that the amount should clear the typical volume of water used on Tenax extraction about 2400 times. This represents unequivocal evidence that the Tenax resin would remove PCBs dissolved in the liquid phase (e.g., overlying or interstitial water) present in the sediment sample and be limited only by compound desorption and not by the Tenax sorption capacity. The results examining the impact of the relationship between the amount of Tenax required and the amount of organic carbon in the sediment extraction indicated that a minimum of 5:1 Tenax:OC ratio be used to conduct Tenax extractions. This will reduce (eliminate) the possibility of re-adsorption by the native OC in the sediment in competition with the Tenax. After ascertaining the best operational conditions for Tenax extractions, two additional methodological uncertainties, the effect of storage time after collection and the preservation method associated with the handling of collected sediment samples were investigated in Chapter 3. The effect of holding time and the preservation method on PCB concentrations from field-collected sediments was examined for a period of 196 d. All samples were held at 4 ºC in the dark and several holding times were chosen. The parameters to track the changes in PCB concentration in two sediments used three exposure metrics: exhaustive solvent extraction, tissue concentrations and Tenax extractions (Chapter 3). The results showed that the total exhaustive concentrations representing the whole sediment concentrations did not significantly change (ANOVA, p> 0.05) in either sediment over the course of 196 d. Similar results were also found for the total Tenax concentrations that represented the bioaccessible sediment concentrations, and for the total organism tissue concentrations representing exposure. The likely equilibrium of PCB in the sediment, their chemical stability of PCB and slow degradation can be underlined as the main factors leading to these results. The long time that legacy contaminants such as PCBs have been in contact with contaminated sites (e.g., Superfund sites) might have contributed to an equilibrium to be reached between the sediment particles and PCB molecules. The significance of this chapter is that sediments collected from PCB-contaminated sites can be stored longer than the 14 d as recommended by current standard protocols without disturbing the measures of bioavailability. The role of organic carbon composition within sediment on contaminant sorption was also investigated to ascertain the effects of type and quantity of OC from different origins on the bioaccessibility of PCBs in contaminated sediments (Chapter 4). Changes in PCB bioaccessibility in sediments amended at either 3 or 6% by dry weight with black carbon (BC), humic acid (HA) or sawdust (SD), showed that the lowest and highest PCB bioaccessibilities were observed in the BC and SD amendments, respectively. Specifically, the total amount of PCBs desorbed ranges from 3 to 27% for BC amendments, 12 to 55% for HA amendments and 16 to 80% for SD amendments. The results showed the influence of OC quantity on bioaccessibility having a much slower desorption of PCBs in 6% amendments compared to 3% amendments, and this finding was most evident in HA and BC amendments. The results also showed that the Tenax technique can be applied to tract the variation in type of carbon and quantity of OC in contaminated sediment to estimate exposure. Finally, the applicability of the Tenax technique as tool to assess the remediation success of PCB-contaminated marine sediments upon AC amendment at either 4.3 or 0.026% AC by dw was examined in Chapter 5. The results showed that bioaccessibility of PCBs was greatly reduced in sediment amended at the higher AC dose (4.3%); while, reduction was also observed even in the sediment amended at 0.026% AC. Furthermore, the results revealed that Tenax concentrations reflected the PCB reduction among AC amended sediments in the same direction as the PCB reduction in the organism bioaccumulation. Overall, this dissertation provides further evidence that the Tenax technique is a rapid, reliable, and cost-effective tool for estimating exposure to recalcitrant organic contaminants such as PCBs from contaminated sites. The applicability of the technique to estimate bioaccessible compound from both freshwater and marine aquatic sediments underline the robustness of the technique to widen its use among risk ecological assessor and researchers.