RESUMO
Targeting the most relevant organic micropollutants (OMP) in routine analysis appears difficult due to formation of transformation products of unknown concentration or toxicity. Performance assessment of water purification processes is still based upon limited target data. Therefore, we broadened the assessment of the removal efficiencies with combined non-target and effect-directed analysis at four riverbank filtration (RBF) sites in Germany. To assess micropollutant elimination, constancy and formation during different seasons, considering local redox conditions, travel distances and total component number in the river, non-target analysis features were grouped into categories. Furthermore, RBF sites were investigated with four endpoints (baseline toxicity, acetylcholinesterase inhibition, antibiotic effects and estrogenic effects) for thin-layer chromatography - effect-directed analysis for the first time. Results showed elimination or reduction of many features and effects, but also constancy and formation of varying proportions. Fall river samples showed precipitation-caused dilution in both tests. Spring samples showed increased effects only in acetylcholinesterase inhibition and estrogenic effects, probably due to phytoestrogens or algae bloom during vegetation period. Sites were ranked considering the total number of features, group proportions, seasonal variations and intensity and number of effects in abstraction wells. Oxic conditions and low initial component numbers in the river (Ruhr sites) resulted in less effects and fewer formations. Longer travel distances were important for a more efficient reduction of effects and features. Combination of non-target and effect-directed analysis proved to be valuable for a more comprehensive assessment of process performance beyond target analysis as also unknown OMP are observed with both methods.
Assuntos
Poluentes Químicos da Água/análise , Filtração/métodos , Alemanha , Oxirredução , Rios , Estações do Ano , Purificação da Água/métodosRESUMO
Effect-directed analysis (EDA) is increasingly used in environmental monitoring to detect and identify key toxicants. High-performance thin-layer chromatography (HPTLC) has proven to be a very suitable fractionation technique for this purpose. However, HPTLC is limited in its separation efficiency. Thus, separated fractions could still contain many different components and identification of the effective substances remains difficult. Therefore, in this study a workflow for selective EDA with two-dimensional HPTLC in combination with high-performance liquid chromatography-high-resolution mass spectrometry (HPLC-HRMS) was developed. The aim of the workflow was the stepwise reduction of the sample complexity in order to reduce the number of signals that could be responsible for the measured effects. As a consequence, the identification of effective substances should be facilitated. The acetylcholinesterase inhibition assay (AChE assay) for the detection of potential neurotoxic compounds was applied for biotesting. The transfer of effective zones from the first to the second dimension and also to the mass spectrometric measurement was enabled by extraction. A proof of concept was performed by spiking six acetylcholinesterase inhibiting substances into three different water matrices that were investigated with the developed workflow. The successful prioritization of all spiked compounds confirmed the efficiency of the workflow, regardless of the sample matrix. Biotesting of different water samples resulted in numerous potentially neurotoxic effects, which overlapped strongly in the first separation dimension. The higher peak capacity reached by two-dimensional HPTLC, on the other hand, resulted in discrete effective zones and enabled the identification of several compounds. For the substances lumichrome, a derivate of riboflavin and paraxanthine as well as for linear alkylbenzene sulfonates that were applied as anionic surfactants in detergents, the inhibiting effect to the AChE could be confirmed.
Assuntos
Inibidores da Colinesterase/análise , Cromatografia em Camada Fina/métodos , Espectrometria de Massas/métodos , Água/química , Acetilcolinesterase/metabolismo , Ensaios Enzimáticos , Fluorescência , Processamento de Sinais Assistido por Computador , Poluentes Químicos da Água/análiseRESUMO
There are thousands of organic trace substances in the environment that are not fully characterized, and evaluation of their relevance to the ecosystem is difficult. Effect-directed analysis (EDA) is a suitable tool to assess the effects of a substance via in-vitro bioassays, which can provide information about the relevance of the substance. High-performance thin-layer chromatography (HPTLC) has been shown to be a good method for fractionation. Environmental samples, however, often have high complexity, which is why the peak capacity of HPTLC is not sufficient. Therefore, this study focused on the development of selective two-dimensional (2D) HPTLC-EDA to increase the peak capacity and facilitate the identification of effective compounds. Thus, only effective zones were selected in the first dimension in terms of heart-cutting and were transferred to the second dimension through elution head-based extraction. Three 2D approaches were developed and validated. The best results in terms of peak capacity and orthogonality were achieved when the retardation factors of the first dimension were used to adjust the mobile phase (MP) for the second dimension. Applying the acetylcholinesterase (AChE) inhibition assay as an example EDA, analysis of spiked surface water by 2D HPTLC-EDA allowed zones with neurotoxic effects to responsible substances to be assigned. The 2D separation reduced the complexity of effective zones and thus facilitated the subsequent identification of effective compounds. Knowledge about a substancés effects enabled assessment of its relevance to the environment.
Assuntos
Fracionamento Químico/métodos , Cromatografia em Camada Fina , Compostos Orgânicos/isolamento & purificação , Bioensaio , Inibidores da Colinesterase/análise , Inibidores da Colinesterase/farmacologia , Colinesterases/metabolismo , Meio Ambiente , Ativação Enzimática/efeitos dos fármacosRESUMO
BACKGROUND: The incidence of cardiovascular disease (CVD) is increasing in industrialized countries. Preventive action is an important factor in minimizing CVD-associated morbidity and mortality. However, it is not known whether gender differences affect CVD or risk factor awareness influencing self-assessment of personal risk and preventive action. OBJECTIVE: This study was performed to assess individual CVD and risk factor awareness, preventive action taken, and barriers to cardiovascular health. METHODS: The study included 573 women and 336 men, randomly chosen to complete an anonymous questionnaire to assess individual CVD and risk factor awareness, preventive action taken, and barriers to cardiovascular health. The data were analyzed using SAS software. RESULTS: Cardiovascular disease was identified in 75% of patients, in both sexes, as the leading cause of death; however, both groups showed significant lack of knowledge about CVD risk factors. Type 2 diabetes was identified correctly in only 27.5%. Preventive action was linked more often to family members in 66.5% of women and 62.8% of men. The primary barrier to cardiovascular health in adults was incorrect assessment of personal CVD risk. More than half of female respondents (56.4%) and male respondents (52.7%) underestimated their risk of CVD. CONCLUSION: Knowledge about risk factors for CVD needs to be improved in members of both sexes. Because women, in particular, have difficulty in correctly assessing their personal CVD risk, future education programs are warranted to inform both women and men about CVD and its risk factors, thereby helping them to correctly assess their individual risk. However, greater effort is needed to inform men, compared with women, about the various ways in which to prevent CVD and to motivate them to take preventive action.