Transfer and effects of 1,2,3,5,7-pentachloronaphthalene in an experimental food chain.

Polychlorinated naphthalenes are environmentally relevant compounds that are measured in biota at concentrations in the µg/kg lipid range. Despite their widespread occurrence, literature data on the accumulation and effects of these compounds in aquatic ecosystems are sparsely available. The goal of this study was to gain insights into the biomagnification and effects of 1,2,3,5,7-pentachloronaphthalene (PeCN52) in an experimental food chain consisting of benthic worms and juvenile rainbow trout. Worms were contaminated with PeCN52 by passive dosing from polydimethylsiloxane silicone. The contaminated worms were then used to feed the juvenile rainbow trout at 0.12, 0.25 or 0.50 µg/g fish wet weight/day, and the resulting internal whole-body concentrations of the individual fish were linked to biological responses. A possible involvement of the cellular detoxification system was explored by measuring PeCN52-induced expression of the phase I biotransformation enzyme gene cyp1a1 and the ABC transporter gene abcb1a. At the end of the 28-day study, biomagnification factors were similar for all dietary intake levels with values between 0.5 and 0.7 kg lipid(fish)/kg lipid(worm). The average uptake efficiency of 60% indicated that a high amount of PeCN52 was transferred from the worms to the fish. Internal concentrations of up to 175 mg/kg fish lipid in the highest treatment level did not result in effects on survival, behavior, or growth of the juvenile trout, but were associated with the induction of phase I metabolism which was evident from the significant up-regulation of cyp1a1 expression in the liver. In contrast, no changes were seen in abcb1a transcript levels.

Fate and effects of ivermectin on soil invertebrates in terrestrial model ecosystems.

The effect of ivermectin on soil organisms was assessed in Terrestrial Model Ecosystems (TMEs). Intact soil cores were extracted from a pasture in England and kept for up to 14 weeks in the laboratory. Ivermectin was applied to the soil surface via spiked cow dung slurry at seven concentration rates ranging from 0.25 to 180 mg/TME, referring to concentrations of 0.19-227 mg ivermectin/kg soil dry weight in the uppermost (0-1 cm) soil layer. After 7, 28 and 96 days following the application soil cores were destructively sampled to determine ivermectin residues in soil and to assess possible effects on microbial biomass, nematodes, enchytraeids, earthworms, micro-arthropods, and bait-lamina feeding activity. No significant effect of ivermectin was found for microbial respiration and numbers of nematodes and mites. Due to a lack of dose-response patterns no effect concentrations could be determined for the endpoints enchytraeid and collembolan numbers as well as total earthworm biomass. In contrast, EC50 values for the endpoint feeding rate could be calculated as 0.46, 4.31 and 15.1 mg ivermectin/kg soil dry weight in three soil layers (0-1, 0-5 and 0-8 cm, respectively). The multivariate Principal Response Curve (PRC) was used to calculate the NOEC(community), based on earthworm, enchytraeid and collembolan abundance data, as 0.33 and 0.78 mg ivermectin/kg soil dw for day 7 and day 96, respectively. The results shown here are in line with laboratory data, indicating in general low to moderate effects of ivermectin on soil organisms. As shown by the results of the bait-lamina tests, semi-field methods such as TMEs are useful extensions of the battery of potential test methods since complex and ecologically relevant endpoints can be included.

Environmental risk assessment of ivermectin: A case study.

The veterinary parasiticide ivermectin was selected as a case study compound within the project ERAPharm (Environmental Risk Assessment of Pharmaceuticals). Based on experimental data generated within ERAPharm and additional literature data, an environmental risk assessment (ERA) was performed mainly according to international and European guidelines. For the environmental compartments surface water, sediment, and dung, a risk was indicated at all levels of the tiered assessment approach. Only for soil was no risk indicated after the lower tier assessment. However, the use of effects data from additional 2-species and multispecies studies resulted in a risk indication for collembolans. Although previously performed ERAs for ivermectin revealed no concern for the aquatic compartment, and transient effects on dung-insect populations were not considered as relevant, the present ERA clearly demonstrates unacceptable risks for all investigated environmental compartments and hence suggests the necessity of reassessing ivermectin-containing products. Based on this case study, several gaps in the existing guidelines for ERA of pharmaceuticals were shown and improvements have been suggested. The action limit at the start of the ERA, for example, is not protective for substances such as ivermectin when used on intensively reared animals. Furthermore, initial predicted environmental concentrations (PECs) of ivermectin in soil were estimated to be lower than refined PECs, indicating that the currently used tiered approach for exposure assessment is not appropriate for substances with potential for accumulation in soil. In addition, guidance is lacking for the assessment of effects at higher tiers of the ERA, e.g., for field studies or a tiered effects assessment in the dung compartment.

Direct and indirect effects of pollutants on algae and algivorous ciliates in an aquatic indoor microcosm.

An aquatic indoor microcosm was used to study effects of the pesticides parathion-methyl and prometryn on phototrophic flagellates (Cryptomonas sp.) and predatory ciliates (Urotricha furcata). Parathion-methyl caused effects to flagellates and ciliates at the range of low mg L(-1), regardless of whether the organisms were exposed separately or combined in the multi-species test system. Prometryn caused effects on the flagellates at low microg L(-1) concentrations, resulting in a NOEC of 6.9 microg L(-1) in the single-species test and a NOEC of 15.2 microg L(-1) in the multi-species microcosm. For ciliates the NOEC decreased by factor 145 in the multi-species test compared to the NOEC of 2.2 mg L(-1) in the single-species test when exposed to prometryn. The lower NOEC for ciliates exposed to prometryn in the microcosm was most likely caused by an indirect effect due to reduced availability of flagellates as food. The measurement of nutrient concentrations in the test media and organisms facilitated the modelling of effects. The presented aquatic indoor microcosm is considered as a tool which could be standardised and applied as an instrument to provide data for higher tier risk assessment.

Eco-labelling of shampoos, shower gels and foam baths.

GOAL, SCOPE AND BACKGROUND: Environmental issues of personal care products have been met with little attention in the past. Monitoring data as well as preliminary environmental risk assessments indicate that some ingredients in personal care products might be relevant pollutants in the environment. Following the precautionary principle, eco-labelling is proposed as an effective tool for source control of one major group of personal care products, shampoos, shower gels and foam baths (SSBs). Eco-labelling is a soft, but effective market driven and product specific approach to lower discharge of environmentally detrimental substances. Products that fulfil the criteria proposed help to minimise the impact of SSBs on the environment. METHODS: Available assessment tools for dangerous substances (e.g. current legislation on environmental risk assessments and classification, and labelling, eco-labelling criteria for similar products, the calculation of the critical dilution volume) were adapted and integrated into the criteria for the eco-labelling of SSBs. RESULTS AND DISCUSSION: A short outline of the eco-labelling criteria developed for SSBs is provided. The basic criteria concern the effects of the substances discharged into the waste water during and after use. Products with an eco-label award may exclusively contain substances for which basic information about their effects on the environment is available. They may not contain persistent, bioaccumulating, toxic or ecotoxicological substances. In addition, the basic criteria include requirements for the container and consumer information. CONCLUSION: The basic criteria for eco-labelling SSBs are based on the actual state of science and are at the same time as simple and transparent as possible to ensure the best applicability. SSBs that comply with the described basic criteria can contribute to a lower chemical burden of waste water treatment plants and surface water. RECOMMENDATION AND OUTLOOK: The proposal for basic criteria described should stimulate discussion on eco-labelling of SSBs. It should help to pass valid criteria supported by authorities, producers and consumer groups for a national or international eco-label, e.g. for the European Flower or the German Blue Angel. In future, the successful introduction of labelled SSBs into the market will raise the awareness of the general public about the environmental effects of personal care products and it will help to promote environmentally compatible products.

Evaluation of measured and predicted environmental concentrations of selected human pharmaceuticals and personal care products.

GOAL, SCOPE AND BACKGROUND: In the past few years, there was an increasing awareness of the occurrence of pharmaceuticals and personal care products (PPCPs) in surface water and drinking water resources, and measurements in surface water, sediment or waste water were done for a number of PPCPs. In the regulatory context, an environmental risk assessment (ERA) has become essential for new PPCPs. Reliably predicted or measured environmental concentrations (PECs or MECs) of chemicals are essential for the exposure assessment, which is one of the two main pillars of environmental risk assessment (ERA). This paper reports on measured data of selected PPCPs in surface waters and compares the measured values with predicted environmental concentrations from exposure models. Such models have been proposed by the European Agency for the Evaluation of Medicinal Products (EMEA) and the Technical Guidance Document on Risk Assessment for New Notified and Existing Chemical Substances (TGD). METHODS: Four pharmaceuticals and one personal care product were in the scope of the investigation reported here: 17alpha-ethinylestradiol, carbamazepine, sulfamethoxazole and iopromide as well as tonalide. Measured environmental concentrations in surface waters for these PPCPs were reviewed in the scientific literature. The appropriateness of these data was evaluated according to criteria for monitoring data recommended by the TGD. A total of 38 references were evaluated with emphasis on the adequacy of chemical analysis and the representativeness of sampling. Measurements of concentrations in surface water (MECsw), which were found to be adequate for use in exposure assessment according to the monitoring quality criteria, were averaged and compared with respective PECs in surface water (PECsw) derived from exposure modelling (cf. EMEA and TGD). RESULTS AND DISCUSSION: Measured environmental concentrations adequate for use in exposure assessment were found in 20 out of 38 references. Several of the measurements from Germany could be used for a comparison with calculated PECs. Average MECs(sw) in Germany were < 0.58 ng/L for 17alpha-ethinylestradiol, 454 ng/L for carbamazepine, 126 ng/L for sulfamethoxazole, 1105 ng/L for iopromide and 311 ng/L for tonalide. In comparison to the measured concentrations, PECs calculated with the model proposed by the EMEA in 2001 were in the same range, but slightly higher than the MECs. The EMEA model from 2001 is based on a production/use volume of the PPCPs. The more recent EMEA model (2003/2005) overestimated the PECs by more than one order of magnitude for carbamazepine and sulfamethoxazole, but underestimated the concentration of 17alpha-ethinylestradiol by a factor of almost 5 compared to the MECs. This model is based on maximum daily doses and the assumption that 1% of the population is consuming the pharmaceutical (default value). Calculations with the European Union System for the Evaluation of Substances (EUSES), which is part of the TGD describing the risk assessment of chemicals and biocides, resulted for the investigated pharmaceuticals in almost the same PECs as derived by the older EMEA model (2001). For the PCP tonalide, to which the recent EMEA model (2003/ 2005) cannot be applied, the PEC was overestimated by a factor of 3 with the older EMEA model (2001), but underestimated with EUSES by a factor of 5 compared to the averaged MECsw in Germany. Conclusions. It was shown that PEC calculations with exposure models provided by EMEA and the TGD, resulted in PECs very close to the corresponding MECs in most cases. However, environmental concentrations can be underestimated by models in cases, where, e.g. due to high lipophilicity, sorption to sewage sludge is assumed which does not occur to that extent under real conditions. Thus, it appears that the exposure models do not come up to the complexity of the real environment. However, the main factor with the highest impact on predicted environmental concentrations and a high degree of uncertainty is the production volume. Recommendations and Outlook. References and their data evaluated as not adequate for use in exposure assessment were mainly rejected due to missing or insufficient specifications related to the sampling procedure and/or representativeness of the samples. Several of the evaluated studies aimed at the introduction and establishment of a new analytical methodology. A detailed description of sampling frequency and pattern, for example, was therefore neglected. Often, a more accurate description of analytical procedure, sampling pattern and statistical analysis of data would be sufficient to provide an adequate basis for exposure assessment and hence establish confidence in environmental risk assessment procedures. For new substances, an exposure assessment is solely based on estimations using environmental fate models. To avoid unacceptable risks for the environment, PECs should not underestimate actual environmental concentrations. Since it was shown that under specific conditions the models applied in this study underestimated measured environmental concentrations, further development of the calculation models appears to be necessary.

Bioaccumulation of 14C-17alpha-ethinylestradiol by the aquatic oligochaete Lumbriculus variegatus in spiked artificial sediment.

A bioaccumulation study was performed with the endobenthic freshwater oligochaete Lumbriculus variegatus MULLER exposed to the radiolabelled synthetic steroid 17alpha-ethinylestradiol (14C-EE2) in a spiked artificial sediment. Concentration of total radioactivity increased constantly and almost linearly during 35 days of exposure. The accumulation factor normalised to worm lipid content and sediment TOC (AFlipid/OC) was 75 at the end of the uptake period, but a steady state was not reached. Uptake kinetics were calculated fitting the measured AFs to a kinetic rate equation for constant uptake from sediment using iterative non-linear regression analysis. After 10 days of elimination in contaminant-free sediment 50% of the accumulated total radioactivity was excreted by the worms. Extracts from L. variegatus sampled at the end of the uptake phase were analysed by thin layer chromatography (TLC). The results showed that 6% of the total radioactivity incorporated by the worms was 14C-EE2. After treatment of extracts with beta-glucuronidase the amount of 14C-EE2 increased to 84%. These results suggest that L. variegatus has the potency to accumulate high amounts of conjugated EE2. Hence, a transfer of EE2 to benthivores and subsequent secondary poisoning of predators might be possible.