Biomonitoring zur wirkungsbezogenen Ermittlung der Schadstoffbelastung in terrestrischen Ökosystemen

Biomonitoring programmes provide relevant information, which may supplement ambient air pollution monitoring or modelling around emission sources. As a prerequisite, assessment scales for biomonitoring data have to be derived based on an objective evaluation of available data, as well as on a scheme of presentation, which is suggestive and easily understandable even for laymen. Based on an evaluation of numerous monitoring programmes, assessment scales for biomonitoring results are derived for plant biomonitoring, which also serve as a basis for the graphical presentation of monitoring results. This study is focussed on bioindicator plants like mosses (passive biomonitoring) and exposed lichens (active biomonitoring), in which 14 metal elements are investigated. As an example, data from a local biomonitoring network around a cement plant were used to demonstrate the use of the assessment scales derived and the presentation scheme developed. Data sets from about 15 moss and 24 lichen biomonitoring programmes, comprising more than 1000 specimens, were sorted by their pollutant characteristics in order to form the database. Data on the metal contents of species demonstrating similar values with respect to growth characteristics and habit, and representing background or low pollution levels, are aggregated and their statistical distributions are evaluated. Spacing of the assessment scales and their colour designations are derived from the 50-, 75-, 90- and 95-percentile values. Graphical presentation allows a comparison of the absolute values of metal contents and a relative association of measured values. Exemplary results from moss and lichen monitoring around a cement plant are generally below or slightly above the median values at background and low-pollution sites. Metal contents are higher in lichens compared to mosses for 7 elements (Cd, Cu, Hg, Pb, Sb, Sn, Zn), and are lower in lichens only for thallium. The assessment scheme presented is mainly aimed at the practitioner in the field of biomonitoring in order to provide a reliable and sound scale of assessment by comparison on an absolute scale rather than presenting the basis of ecological risk assessment. Differences in metal content of co-located samples of various moss species and possible correction procedures are briefly discussed- as well as the consequences of pooling monitoring data across various moss species for the quality of assessment scales. Further evaluations shall focus on species-specific rather than on pooled databases and will investigate the consequences of the use of correction factors when extrapolating metal data from one monitoring species to another.     

Photocatalytic reduction of carbon dioxide over Cu/TiO<Subscript>2</Subscript> photocatalysts

The photocatalytic reduction of CO₂ with H₂O was investigated using Cu/TiO₂ photocatalysts in aqueous solution. For this purpose, Cu/TiO₂ photocatalysts (with 0.2, 0.9, 2, 4, and 6 wt.% of Cu) have been synthesized via sol-gel method. The photocatalysts were extensively characterized by means of inductively coupled plasma optical emission spectrometry (ICP-OES), N₂ physisorption (BET), XRD, UV-vis DRS, FT-IR, Raman spectroscopy, TEM-EDX, and photoelectrochemical measurements. The as-prepared photocatalysts contain anatase as a major crystalline phase with a crystallite size around 13 nm. By increasing the amount of Cu, specific surface area and band gap energy decreased in addition to the formation of large agglomeration of CuO. Results revealed that the photocatalytic reduction of CO₂ decreased in the presence of Cu/TiO₂ in comparison to pure TiO₂, which might be associated to the formation of CuO phase acting as a recombination center of generated electron-hole pair. Decreasing of photoactivity can also be connected with a very low position of conduction band of photocatalysts with high Cu content, which makes H₂ production necessary for CO₂ reduction more difficult.     

Occurrence and behavior of wastewater indicators in the Santa Ana River and the underlying aquifers.

The occurrence and behavior of wastewater indicator compounds in the Santa Ana River (SAR) water and the underlying aquifer recharged by the SAR has been studied. The SAR contains a high proportion of tertiary treated wastewater effluents, up to 100% during summer and fall. The following water quality parameters were quantified: four specific wastewater indicator compounds, ethylene diaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), a naphthalene dicarboxylate (NDC) isomer, alkylphenol polyethoxy carboxylates (APECs), and selected haloacetic acids (HAAs), nitrate, dissolved oxygen (DO), DOC, total carbohydrate, and phenolic substances. Statistical analysis indicated that normal distribution was adequate to describe the probability distribution of the constituents in most cases. In the river, the concentrations of wastewater indicator compounds decreased as the fraction of storm runoff increased. EDTA and NDC were detected in a monitoring well near the river and in two production wells 1.8 and 2.7 km down gradient with little apparent attenuation. By contrast, NTA, APECs, bromochloro- and dibromoacetic acids appeared to be attenuated significantly during infiltration of river water and groundwater transport.     

The mental health of expatriate and Kosovar Albanian humanitarian aid workers

The mental health consequences of exposure to traumatic events and the risk factors for psychological morbidity among expatriate and Kosovar Albanian humanitarian aid workers have not been well studied. In June 2000, we used standardised screening tools to survey 285 (69.5%) of 410 expatriate aid workers and 325 (75.8%) of 429 Kosovar Albanian aid workers from 22 humanitarian organizations that were implementing health programmes in Kosovo. The mean number of trauma events experienced by expatriates was 2.8 (standard deviation: 2.7) and by Kosovar staff 3.2 (standard deviation: 2.8). Although only 1.1% of expatriate and 6.2% of Kosovar aid workers reported symptoms consistent with the diagnosis for post-traumatic stress disorder, 17.2% and 16.9%, respectively, reported symptoms satisfying the definition of depression. Regression analysis demonstrated that the number of trauma events experienced was significantly associated with depression for the two sets of workers. Organisational support services may be an important mediating factor and should be targeted at both groups.     

Concentrations and specific loads of brominated flame retardants in sewage sludge

Many substances related to human activities end up in wastewater and accumulate in sewage sludge. The present study focuses on two classes of brominated flame retardants: polybrominated diphenyl ethers (BDE28, BDE47, BDE49, BDE66, BDE85, BDE99, BDE100, BDE119, BDE138, BDE153, BDE154, BDE183, BDE209) and hexabromocyclododecane (HBCD) detected in sewage sludge collected from a monitoring network in Switzerland. Mean concentrations (n=16 wastewater treatment plants) were 310, 149, 95 and 17microg per kg dry matter for decaBDE, HBCD, penta- and octaBDE, respectively. These numbers correspond well with other studies from European countries. DecaBDE, HBCD, penta- and octaBDE showed average specific loads (load per connected inhabitant per year) in sludge of 6.1, 3.3, 2.0 and 0.3mgcap(-1)yr(-1), respectively. This is in line with consumption and storage of the compounds in the environment and the anthroposphere. Discrepancies observed for octaBDE and HBCD can be explained by the release from materials where these compounds are incorporated in and/or their degradation during anaerobic sludge treatment. Loads from different types of monitoring sites showed that brominated flame retardants ending up in sewage sludge originate mainly from surface runoff, industrial and domestic wastewater.     

Impact of a NO₂-regenerated diesel particulate filter on PAH and NPAH emissions from an EURO IV heavy duty engine

In this study the emissions of polycyclic aromatic hydrocarbons (PAH) and their nitro-derivates (NPAH) from a modern heavy duty engine were analysed. Focus was on the effects of the aftertreatment system. It consisted of an oxidation catalyst coupled to a diesel particulate filter (DPF). In such systems the process of PAH and NPAH degradation may compete with the NPAH formation. Scope of the study was to explain to which extent modern DPF could support the formation of highly mutagenic NPAH by nitration of pre-existing PAH. It was found that the diesel trap reduced the total amount of PAH and NPAH emitted both at low load and high load. Nevertheless, at low load the lower temperatures and the higher NO(2) concentration furnished better conditions for PAH nitration while they were more adverse to NPAH degradation. These effects were NPAH-specific. For these reasons, some NPAH like 3-nitrophenanthrene were still efficiently degraded but others were newly formed. For instance emissions of the highly toxic 1-benzo(a)pyrene and 6-nitrobenzo(a)pyrene where increased by a factor 15 at low load and, even if in lower amount, were formed also at high load. The super-mutagen 1,6-dinitropyrene, which was not present in raw exhaust, could be found only after the DPF, indicating a new formation. In regard to emissions from the active regeneration mode, tremendous high emissions of 1-nitropyrene were reported. More accurate investigation of such a regeneration mode would be of great interest for the future.     

Detecting diclofenac in livestock carcasses in India with an ELISA: a tool to prevent widespread vulture poisoning

Diclofenac, a non-steroidal anti-inflammatory drug (NSAID), has caused catastrophic vulture declines across the Indian sub-continent. Here, an indirect ELISA is used to detect and quantify diclofenac in 1251 liver samples from livestock carcasses collected across India between August 2007 and June 2008, one to two years after a ban on diclofenac manufacture and distribution for veterinary use was implemented. The ELISAs applicability was authenticated with independent data obtained using LC-ESI/MS. Of 1251 samples, 1150 (91.9%) were negative for diclofenac using both methods, and 60 (4.8%) were positive at 10-4348 and 10-4441 μg kg(-1) when analysed by ELISA and LC-ESI/MS, respectively. The residue level relationship in the 60 positive samples was highly significant (p < 0.001, r(2) = 0.644). Data suggest that this immunological assay could be used not only for cost effective sample screening, but also for residue level semi-quantification.