Long-term trends in Swiss rivers sampled continuously over 39 years reflect changes in geochemical processes and pollution

Environmental Science and Pollution Research - Long-term changes of 14 water constituents measured in continuously and water discharge proportionally collected samples of four Swiss rivers over a...     

Interested consumers’ awareness of harmful chemicals in everyday products

Background

Everyday products can contain a multitude of harmful substances unnoticed by most consumers, because established risk communication channels reach only part of the society. The question is, whether at least interested and informed consumers are able to use risk communication tools and assess harmful chemicals in products.

Results

An online survey investigated the awareness of 1030 consumers on harmful substances in everyday items. Participating consumers’ education level, knowledge in chemistry, and motivation were above society’s average. Although a large number of responses showed that survey participants were familiar with several aspects of the issue, the results revealed that knowledge in chemistry helped, but was not enough. Many participants assumed that products with an eco-label, natural personal care products, products without hazard pictograms or products produced in the European Union would not contain harmful substances. Most participants indicated to use hazard pictograms, information on the packaging, reports in the media, and environmental and consumer organizations as information sources, while information by authorities and manufacturers were not named frequently and did not receive high confidence. Smartphone applications were not indicated by many participants as information sources. The information sources most trusted were environmental and consumer organizations, hazard pictograms, and lists of ingredients on the containers. The declared confidence in certain risk communication instruments did not always correspond to the use frequencies indicated. Nearly all participants considered legislators as responsible for the reduction of harmful substances in consumer products.

Conclusions

Misconceptions about harmful substances in products can be dangerous for the personal health and the environment. The survey indicates that motivation, educational level, and chemical expertise do not automatically provide an appropriate understanding of harmful substances in products. If well-informed consumers are not sufficiently capable to use risk information elements as revealed in this study, then this will be even more the case for the general public. Consumer awareness should be stipulated by an improved information strategy about chemical risks in consumer products with an extensive participation of the target groups and by more efforts by authorities and manufactures to build trust and to provide easily understandable information.

     

Determination of trace perchlorate in water: a simplified method for the identification of potential interferences

Background

Perchlorate contamination of water and food poses potential health risks to humans due to the possible interference of perchlorate with the iodide uptake into the thyroid gland. Perchlorate has been found in food and drinking, surface, or swimming pool waters in many countries, including the United States, Canada, France, Germany, and Switzerland, with ion chromatography (IC) being the preferred analytical method. The standardization of a robust ion chromatographic method is therefore of the high interest for public health and safety. This article summarizes the experiments and results obtained from analyzing untreated samples, considering the sample’s electrical conductance as guidance for direct sample injection as described in EPA 314.0.

Results

The suitability of ion chromatography with suppressed conductivity detection was tested for water samples in order to check the influence of matrix effects on the perchlorate signal of untreated samples. A sample injection volume of 750 μL was applied to the selected 2 mm?IC?column. The IC?determination of perchlorate at low µg/L levels is challenged by the presence of high loads of matrix ions (e.g., chloride, nitrate, carbonate, and sulfate at 100 mg/L and above). Perchlorate recovery is impaired with the increasing matrix ion concentrations, and its chromatographic peak is asymmetric particularly at low perchlorate concentrations. The identification of the individual maximum concentration of interfering anions like chloride, nitrate, and sulfate that influence perchlorate recovery helps to reduce the number of sample preparation steps or an obligatory measurement of the electrical conductivity of the sample. Within the scope of this study, samples containing less than 125 mg/L of either anion did not need sample preparation.

Conclusion

The identification of the maximum concentration of interfering anions like chloride, nitrate, and sulfate influencing perchlorate recovery provides a simplified alternative to the EPA 314.0 method. This approach reduces unnecessary sample preparation steps while allowing a reliable prognosis of possible interferences and maintaining result quality. This study was performed to support the development of a respective international standard, which is being established by the International Organization for Standardization (ISO). The results of the study are also intended to be used as guidance for interested laboratories to optimize the analytical workflow for trace perchlorate determination.

     

Methane and nitrous oxide emissions from a subtropical coastal embayment (Moreton Bay,Australia)

Surface water methane (CH₄) and nitrous oxide (N₂O) concentrations and fluxes were investigated in two subtropical coastal embayments (Bramble Bay and Deception Bay, which are part of the greater Moreton Bay, Australia). Measurements were done at 23 stations in seven campaigns covering different seasons during 2010–2012. Water–air fluxes were estimated using the Thin Boundary Layer approach with a combination of wind and currents-based models for the estimation of the gas transfer velocities. The two bays were strong sources of both CH₄ and N₂O with no significant differences in the degree of saturation of both gases between them during all measurement campaigns. Both CH₄ and N₂O concentrations had strong temporal but minimal spatial variability in both bays. During the seven seasons, CH₄ varied between 500% and 4000% saturation while N₂O varied between 128 and 255% in the two bays. Average seasonal CH₄ fluxes for the two bays varied between 0.5 ± 0.2 and 6.0 ± 1.5 mg CH₄/(m²·day) while N₂O varied between 0.4 ± 0.1 and 1.6 ± 0.6 mg N₂O/(m²·day). Weighted emissions (t CO₂-e) were 63%–90% N₂O dominated implying that a reduction in N₂O inputs and/or nitrogen availability in the bays may significantly reduce the bays' greenhouse gas (GHG) budget. Emissions data for tropical and subtropical systems is still scarce. This work found subtropical bays to be significant aquatic sources of both CH₄ and N₂O and puts the estimated fluxes into the global context with measurements done from other climatic regions.     

Two‐Stage Ditch Floodplains Enhance N‐Removal Capacity and Reduce Turbidity and Dissolved P in Agricultural Streams

Two‐stage ditches represent an emerging management strategy in artificially drained agricultural landscapes that mimics natural floodplains and has the potential to improve water quality. We assessed the potential for the two‐stage ditch to reduce sediment and nutrient export by measuring water column turbidity, nitrate (NO₃^?), ammonium (NH₄⁺), and soluble reactive phosphorus (SRP) concentrations, and denitrification rates. During 2009‐2010, we compared reaches with two‐stage floodplains to upstream reaches with conventional trapezoid design in six agricultural streams. At base flow, these short two‐stage reaches (<600 m) reduced SRP concentrations by 3‐53%, but did not significantly reduce NO₃^? concentrations due to very high NO₃^? loads. The two‐stage also decreased turbidity by 15‐82%, suggesting reduced suspended sediment export during floodplain inundation. Reach‐scale N‐removal increased 3‐24 fold during inundation due to increased bioreactive surface area with high floodplain denitrification rates. Inundation frequency varied with bench height, with lower benches being flooded more frequently, resulting in higher annual N‐removal. We also found both soil organic matter and denitrification rates were higher on older floodplains. Finally, influence of the two‐stage varied among streams and years due to variation in stream discharge, nutrient loads, and denitrification rates, which should be considered during implementation to optimize potential water quality benefits.     

Occurrences and potential risks of 16 fragrances in five German sewage treatment plants and their receiving waters

Fragrances are used in a wide array of everyday products and enter the aquatic environment via wastewater. While several musk compounds have been studied in detail, little is known about the occurrence and fate of other fragrances. We selected 16 fragrance compounds and scrutinized their presence in Bavarian sewage treatment plants (STP) influents and effluents and discussed their ecological risks for the receiving surface waters. Moreover, we followed their concentrations along the path in one STP by corresponding time-related water sampling and derived the respective elimination rates in the purification process. Six fragrance substances (OTNE, HHCB, lilial, acetyl cedrene, menthol, and, in some grab samples, also methyl-dihydrojasmonate) could be detected in the effluents of the investigated sewage treatment plants. The other fragrances under scrutiny were only found in the inflow and were eliminated in the purification process. Only OTNE and HHCB were found in the receiving surface waters of the STP in congruent concentrations, which exceeded the preliminary derived environmental thresholds by a factor of 1.15 and 1.12, respectively, indicating potential risks. OTNE was also detected in similar concentration ranges as HHCB in muscles and livers of fish from surface waters and from ponds that are supplied with purified wastewater. The findings show that some fragrance compounds undergo high elimination rates, whereas others—not only musks—are present in receiving surface water and biota and may present a risk to local aquatic biota. Hence, our results suggest that the fate and potential effects of fragrance compounds in the aquatic environment deserve more attention.     

Kosovo-Konflikt: Ökologische Auswirkungen

10 years ago, the WWF (World Wide Fund for Nature) began to support the work of environmental protection in the countries of Eastern Europe. A main topic is the Danube-Carpathian Program. With the beginning of the bombardements, connected with great amounts of chemicals released directly and as clouds from the fires and explosions, the question raises: What are the consequences for mankind and nature? Is there a risk for the Danube-Carpathian Program? The WWF feels responsible for reporting about these consequences. In July 1999, a group of two Oil Experts and two scientists (each a chemist and a toxicologist) visited Belgrad, Pan?evo and Novi Sad, took samples of soil and water, and estimated the contents of dangerous substances. The first findings and the first consequences for nature and human health are described.     

Fragrances in the Environment: Pleasant odours for nature? (9 pp)

Goal, Scope and Background Fragrance preparations or perfumes are used in an increasing variety of applications, as for example washing, cleansing, personal care products, consumer goods or in applications to modify indoor air. However, up to now, little is known to the general or scientific public about their chemical identity and the use pattern of single substances, not even for high production volume chemicals. Some toxicological data are published for a comparatively small number of substances with a focus on sensitisation and dermal effects, while other effects are neglected. Information on ecotoxicity and environmental fate are rare, especially for long-term exposure. Data for a detailed hazard and risk analysis are available in exceptional cases only. According to the current legal situation, fragrance industry is self-regulated, which means that pre-market risk evaluation is not required for most fragrances. Odour and the ability to smell play a major role for wildlife for all taxonomic groups. Reproductive and social behaviour, defence, communication and orientation depend on volatile compounds which can be identical to those used in fragrance preparations. Our interdisciplinary approach leads to the question of whether and, if so, to what extent anthropogenic fragrances may influence life and reproduction of organisms in the environment. Main Features Information from literature on use, exposure and biological effects was combined to analyse the state of knowledge. Following an overview of the amounts of fragrances used in different consumer products and their release into the environment, the roles of odours in nature are shown for a selection of compounds. Existing regulation was analysed to describe the data basis for environmental risk evaluation. Finally, recommendations for further action are derived from these findings. Results Three main results were elaborated: First, fragrance substances are continuously discharged in large amounts into the environment, especially via the waste water. Second, there are some indications of negative effects on human health or the environment, although the data basis is very thin due to the self regulation of the fragrance industry and the regulatory situation of fragrance substances. Third, many odoriferous substances used by man are identical to those which are signal substances of environmental organisms at very low concentrations, thus giving rise to specific mode of actions in the ecosystem. Recommendations For the adequate risk assessments of fragrances, test results on their unspecific as well as their specific effects as signal substances are needed. This would imply prioritisation methods and development of useful test methods for specific endpoints for appropriate risk assessments. Before a comprehensive testing and evaluation of results has been finished, a minimization of exposure should be envisaged. Eco-labelling of products containing acceptable fragrance ingredients could be a first step and provide consumers with the respective information. Transparency concerning the fragrance ingredients used and their biological potency will help to build up confidence between producers and consumers. Conclusions and Perspectives The interdisciplinary approach, bringing together chemical, biological, toxicological and ecotoxicological data with information provided by manufacturers and with legal and consumer aspects, offers new insights into the field of fragrance substances used in consumer products. The amounts and application fields of fragrance substances increases while fate and effects in the environment are hardly known. The current legal situation is not suited to elucidate the effects of fragrances on human health and the environment sufficiently, especially as it was shown that fragrances may play a considerable role in the ecosystem on the behaviour of organisms. According to the precautionary principle, the lack of knowledge should best be tackled by reducing exposure, especially for compounds such as fragrance substances where no ethical reasons object a substitution by less hazardous chemicals. ESS-Submission Editor: Dr. Thomas Knacker (th-knacker@ect.de)