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For analysing element input into ecosystems and associated risks due to atmospheric deposition, element concentrations in moss provide complementary and time-integrated data at high spatial resolution every 5 years since 1990. The paper reviews (1) minimum sample sizes needed for reliable, statistical estimation of mean values at four different spatial scales (European and national level as well as landscape-specific level covering Europe and single countries); (2) trends of heavy metal (HM) and nitrogen (N) concentrations in moss in Europe (1990-2010); (3) correlations between concentrations of HM in moss and soil specimens collected across Norway (1990-2010); and (4) canopy drip-induced site-specific variation of N concentration in moss sampled in seven European countries (1990-2013). While the minimum sample sizes on the European and national level were achieved without exception, for some ecological land classes and elements, the coverage with sampling sites should be improved. The decline in emission and subsequent atmospheric deposition of HM across Europe has resulted in decreasing HM concentrations in moss between 1990 and 2010. In contrast, hardly any changes were observed for N in moss between 2005, when N was included into the survey for the first time, and 2010. In Norway, both, the moss and the soil survey data sets, were correlated, indicating a decrease of HM concentrations in moss and soil. At the site level, the average N deposition inside of forests was almost three times higher than the average N deposition outside of forests.

Background, Aim and Scope: Nonylphenol (NP) can be detected in the aquatic environment all over the world. It is applied as a technical mixture of isomers of which 353-NP is the most relevant both in terms of abundance (about 20% of total mass) and endocrine potential. 353-NP is metabolised in sewage sludge. The aims of the present study were to determine and to compare the acute toxicity of t-NP, 353-NP and its metabolites as well as to discuss if the toxicity of 353-NP changes during degradation., Materials and Methods: 353-NP and two of its metabolites were synthesised. The zebrafish embryo test was performed according to standard protocols. Several lethal and non-lethal endpoints during embryonal development were reported. NOEL, LOEL and EC50 were calculated., Results: All tested compounds caused lethal as well as non-lethal malformations during embryo development. 353-NP showed a higher toxicity (EC50 for lethal endpoints 6.7 mg/L) compared to its metabolites 4-(3.5-dimethyl-3-heptyl)-2-nitrophenol (EC50 13.3 mg/L) and 4-(3,5-dimethyl-3-heptyl)-2-bromophenol (EC50 27.1 mg/L)., Discussion: In surface water, concentrations of NP are far below the NOEC identified by the zebrafish embryo test. However, in soils and sewage sludge, concentrations may reach or even exceed these concentrations. Therefore, sludge-treated sites close to surface waters should be analysed for NP and its metabolites in order to detect an unduly high contamination due to runoff events., Conclusions: The results of the present study point out that the toxicity of 353-NP probably declines during metabolisation in water, sediment and soil, but does not vanish since the major metabolites exhibit a clear toxic potential for zebrafish embryos., Recommendations and Perspectives: Metabolites of environmental pollutants should be included in the ecotoxicological test strategy for a proper risk assessment.

Goal, Scope and Background: Ethoxyresorufin-O-deethylase (EROD) is a well-accepted marker for biological effects in fish and is, therefore, part of numerous monitoring programmes. EROD activity was measured in livers of dab (Limanda limanda) from the German Bight (North Sea) from 1995 to 2003. The aim of the present long-term study was (a) time trend monitoring of EROD activity of dab from the German Bight and (b) to elucidate the needs for a successful application of EROD activity as an early warning system., Methods: EROD activities were determined fluorimetrically in dab liver microsomes, using resorufin as an external standard. The limit of detection (LD) and the limit of quantification (LQ) were calculated. Results were referred to protein concentrations., Results and Discussion: EROD activities of 610 female dab caught in different seasons between January 1995 and August 2003 were analyzed individually. Activities varied from < LD to 1768 pmol/(min mg protein) and showed an annual cycle as well as significant differences between the years. Highest EROD activities were observed in early summer and lowest activities during the winter period. In autumn 2002, significantly elevated EROD activities were detected, possibly related to effects of the River Elbe flood event. Two scenarios with different EROD baseline data are presented to discuss the prerequisites for the use of EROD as a monitoring tool. The comparison of these scenarios underlines the importance of appropriate season-specific baseline data., Conclusion: The use of EROD as an early warning tool for contaminant effects in dab in the German Bight has different prospects during the year, because, due to the high background variability, elevated EROD activities are less easy to detect in spring/ summer than during the remaining times of the year., Recommendation and Outlook: The availability of site-specific data on the EROD baseline level, its random variation and its annual cycle is a necessary prerequisite for monitoring. If monitoring is to be carried out only for a limited time period of the year, a season with low background variability in EROD activity (autumn) should be chosen to avoid the need for a compensation of the temperature-triggered shift in sexual cycles and the resulting changes in EROD activity.