Deciduous shrubs for ozone bioindication: Hibiscus syriacus as an example

Ozone-like visible injury was detected on Hibiscus syriacus plants used as ornamental hedges. Weekly spray of the antiozonant ethylenediurea (EDU, 300 ppm) confirmed that the injury was induced by ambient ozone. EDU induced a 75% reduction in visible injury. Injury was more severe on the western than on the eastern exposure of the hedge. This factor of variability should be considered in ozone biomonitoring programmes. Seeds were collected and seedlings were artificially exposed to ozone in filtered vs. not-filtered (+30 ppb) Open-Top Chambers. The level of exposure inducing visible injury in the OTC seedlings was lower than that in the ambient-grown hedge. The occurrence of visible injury in the OTC confirmed that the ozone sensitivity was heritable and suggested that symptomatic plants of this deciduous shrub population can be successfully used as ozone bioindicators. EDU is recommended as a simple tool for diagnosing ambient ozone visible injury on field vegetation.     

Long-term (1992-2004) record of lead, cadmium, and zinc air contamination in Warsaw, Poland: Determination by chemical analysis of moss bags and leaves of Crimean linden

Between 1992 and 2004, air contamination with lead (Pb), cadmium (Cd), and zinc (Zn) in Warsaw, Poland, was monitored annually with moss (Sphagnum fallax) bags on a network of 230 sites covering the entire city. During the study the highest contamination was near the Warszawa Steel Mill, northwestern Warsaw. Lead concentrations in moss bags decreased in time, while those of Cd and Zn did not show clear trends. Between 1994 and 2004, Pb, Cd, and Zn were also monitored in the Crimean linden (Tilia Euchlora) foliage along the main city avenue and in a northwestern warsaw park. Lead concentrations decreased more near the avenue than in the park, indicating that the phasing-out of leaded gasoline had a major effect on reduced Pb contamination in Warsaw. At the same time, foliar concentrations of Cd and Zn in both areas decreased much less.     

Analyses of platinum group elements in mosses as indicators of road traffic emissions in Austria

The concentrations of platinum group elements (PGE; platinum, palladium, rhodium) and 17 other elements in mosses growing at 32 sampling sites along 12 roads in Austria were analysed. The study included passive monitoring of naturally growing mosses with an experimental design using mosses samples exposed in a tunnel experiment. PGEs (Pt, Pd, Rh) were analysed by ICP-MS (ELAN DRC II, Perkin Elmer SCIEX) according to EN ISO 17294-2 Tl.29. Mean concentrations of PGEs in five moss species were: Pt 7.07±9.97, Pd 2.8±5.2 und Rh 0.6±0.8 ng g⁻¹ dry weight. This is comparable to data derived from measurements of gasoline autocatalyst emissions or airborne particles (<10 μm). Compared to soils and road dust along highways, concentrations in mosses were lower by a factor of ten, compared to grasses they were comparable or somewhat higher. The ratios between the various PGEs were calculated as follows (mean values): Pt/Pd 7.9±10.2, Pt/Rh 12.6±8.3 and Pd/Rh 3.7±2.2. The number of light duty vehicles (<3.5 t) and the distance from the road were the main influential factors for PGE concentrations. Especially strong correlations could be found between Pt and Sb, Cu, Zn, and Cd (in decreasing order), which are all elements derived mainly from road traffic emissions. Cluster analysis (Partioning Around Medoids Method) separated elements derived mainly from soil dust (Ca, Al). An analysis of spatial deposition patterns of PGEs showed a reciprocal decrease of concentrations with increasing distance from the road, reaching background values at distances between 10 and 200 m, sometimes even more, but outside the spatial range of our investigation.     

Settlement seasonality and temporal changes in hard substrate macrozoobenthic communities of Lesina Lagoon (Apulia, Southern Adriatic Sea)

The macrofauna settling on experimental substrates was studied at two sites of the Lesina Lagoon to test its possible role in monitoring ecological variations in a brackish-water ecosystem. The community settlement was seasonally investigated on 3-month-old wooden poles; the development was monitored from 2001 to 2005. Comparisons with benthic assemblages settled on 10-yr-old poles were also performed. The main hydrological parameters were periodically measured during the study. A total of 38 species were collected. The assemblage reached the highest development in the central lagoon, showing relevant carbonate structures which supported a rich vagile fauna. Close to the sea-water inlet species richness and abundance values were lower, with the disappearance of some brackish-water species. A remarkable salinity drop during 2004 produced some faunistic changes in the assemblages, which however maintained different structures between the study sites, thus confirming macrozoobenthos as an efficient bioindicator of different environmental conditions for transition biotopes and a useful investigation tool in monitoring programmes.     

Isolating the impact of sediment toxicity in urban streams

Several factors can contribute to the ecological degradation of stream catchments following urbanization, but it is often difficult to separate their relative importance. We isolated the impact of polluted sediment on the condition of an urban stream in Melbourne, Australia, using two complementary approaches. Using a rapid bioassessment approach, indices of stream condition were calculated based on macroinvertebrate field surveys. Urban stream reaches supported impoverished macroinvertebrate communities, and contained potentially toxic concentrations of heavy metals and hydrocarbons. Using a field microcosm approach, a bioassay was carried out to assess sediment pollution effects on native macroinvertebrates. Sediment from urban sites substantially altered the microcosm macroinvertebrate community, most likely due to elevated heavy metal and hydrocarbon concentrations. Macroinvertebrate surveys combined with a bioassay approach based on field microcosms can help isolate the effect of stream pollutants in degraded ecosystems.     

Can behavioural responses of Lumbriculus variegatus (Oligochaeta) assess sediment toxicity? A case study with sediments exposed to acid mine drainage

The São Domingos mine (Portugal) is, potentially, a good site for ecotoxicological studies, due to a pH and metal gradient of acid mine drainage. In this study, the toxicity of several mine sediments was evaluated using the aquatic oligochaete Lumbriculus variegatus as a test organism. Our hypothesis was that exposure to contaminated sediments would cause behavioural early warning responses in L. variegatus. Five sites, with pH ranging from 2.5 to 6.5, and with associated metals, were investigated. The results showed poor sediment quality in most of the collected sediments and Fe, S and As were the dominant elements in the samples. High mortalities were observed, ranging from 32.6 to 100%, indicating severe contamination. The collected sediments did not support good L. variegatus growth and significantly changed its behaviour. Early warning responses consisted of decreased locomotion and decreased peristaltic movements. A behaviour inhibition will affect the ecosystem balance by limiting the organisms' ability to avoid capture, which leads to a higher risk of predation.     

Pilot study on road traffic emissions (PAHs,heavy metals) measured by using mosses in a tunnel experiment in Vienna,Austria

BACKGROUND, AIMS AND SCOPE: Over the last few years there has been extensive research for new indicators providing information about deposition resulting from road traffic and tunnel experiments received special attention in emission research. Mosses have been used for the estimation of atmospheric heavy metal and PAH depositions for more than three decades, although they were used only a few times for estimating ambient air pollution caused by traffic. In the current study, the suitability of using a moss species for monitoring road traffic emissions inside a tunnel was evaluated. This was a first-time ever attempt to use plants (mosses) as bioindicators in a tunnel experiment. Specifically, two relevant questions were examined: 1) Do mosses accumulate toxic substances derived from road traffic emissions under the extremely adverse conditions which can be found in a tunnel, and 2) Which substances can mainly be attributed to road traffic emissions and therefore be taken as efficient and reliable indicators for motor vehicles? METHODS: For the first time a biomonitor (the moss species Hylocomium splendens (Hedwig) B.S.G.) was used in a road tunnel experiment to analyse emissions from road traffic. Moss samples were exposed for four weeks in wooden frames (size 10 cm x 10 cm), covered by a thin plastic net with a mesh size of 1 cm x 1 cm. 17 elements, mainly heavy metals, and the 16 EPA-PAHs together with coronene were analysed by ICP-AES, AAS and GC-MSD. RESULTS: Enrichment factors, calculated by comparing post-experiment concentrations to those of a background site, were high for most PAHs, especially benzo(g,h,i)perylene (150.7), coronene (134.7), benzo(a)anthracene (125.0), indeno(1,2,3-c,d)pyrene (79.8), chrysene (78.1), pyrene (69.6) and benzo(b)-fluoranthene (67.4), and among the other elements for Sb (73.1), Mo (59.6), Cr (33.9), As (24.1), Cu (19.6), and Zn (17.1). All these substances can thus be taken as indicators for road traffic pollution. Concentrations were also significantly higher in the tunnel mosses for all investigated substances than along busy roads outside tunnels. Cluster analysis revealed groups of substances which could sensibly be attributed to various sources (abrasion processes, Diesel combustion) and enrichment in the various particle size classes. DISCUSSION: The extreme high concentrations in the analysed moss samples from inside the tunnel were due to higher concentrations in the ambient tunnel air, and the fact that already deposited chemical substances are not lost by rain, as well as efficient uptake capacities even under the extremely adverse conditions in a tunnel. In accordance with previous studies our results suggest that PAHs are better indicators for emissions from the burning process than heavy metals. CONCLUSIONS: As in open fields, mosses are suitable indicators for monitoring traffic emissions in tunnels. In addition to biomonitoring in open fields, in tunnel experiments mosses are even better indicators, because the confounding effects of other sources of pollution and the 'noise' in the accumulation process (e.g. washout through wet deposition) are minimised. The results of our study demonstrate the usefulness of mosses for surveying heavy metals and PAH emissions and deposition arising from road traffic sources, even under the extremely adverse conditions of the tunnel environment. RECOMMENDATION: It can be considered that biomonitors like mosses are a suitable alternative to technical particle filters inside tunnels. They are easy to handle, low in costs and valuable information regarding traffic emissions can be obtained. PERSPECTIVE: The results of this pilot-study proved the feasibility of the method, however, should be corroborated by further investigations based on a sample set that allows for generalization of the findings and might even include other moss species. A comparison of technical measurements with the biomonitoring method could lead to a more general acceptance of the results.     

Tropical Coastal Organisms as Qualitative Indicators of Mercury and Organomercury for Sustainable Use of Living Resources

Organisms sensitive to ambient environment are used as bioindicators in monitoring pollution. The present investigation is designed to measure the extent of mercury and organomercury levels in selective biota of different trophic levels inhabiting in the coastal environment of Sunderban Biosphere Reserve, eastern part of India. The primary objective of this work is to provide baseline data for future environmental quality programme and to ascertain the suitability of these organisms to be used as bioindicator species of pollution. The seagrass (Porterasia coarctata), macrobenthos (polychaetes, gastropods and bivalve molluscs) and pelagic finfishes were collected from sites of different physiochemical characteristics. Concentration of total mercury was determined by cold vapour atomic absorption spectrophotometry technique (CVAAS) using a Perkin-Elmer 2380 AAS equipped with MHS 10.Both mercury and organomercury levels showed considerable interspecific and regional variations which reflected the feeding strategy of these animals and also the location of stations. The bivalve molluscs showed a high degree of organ-specificity in accumulation which might be attributed to the ion exchange activity of mucous membrane covering gill and mantle. Mercury levels in various compartments did not reveal any regular temporal variations but showed a slight increase in the late monsoon months indicating the apparent influence of river run-off and reduction in salinity in the ambient medium. A continuous monitoring programme is recommended in order to clarify the present trend and to establish the studied organisms as indicator species.     

Seasonal comparison of moss bag technique against vertical snow samples for monitoring atmospheric pollution

This is the first study seasonally applying Sphagnum papillosum moss bags and vertical snow samples for monitoring atmospheric pollution.Moss bags,exposed in January,were collected together with snow samples by early March 2012 near the Harjavalta Industrial Park in southwest Finland.Magnetic,chemical,scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDX),K-means clustering,and Tomlinson pollution load index(PLI)data showed parallel spatial trends of pollution dispersal for both materials.Results strengthen previous findings that concentrate and slag handling activities were important(dust)emission sources while the impact from Cu–Ni smelter's pipe remained secondary at closer distances.Statistically significant correlations existed between the variables of snow and moss bags.As a summary,both methods work well for sampling and are efficient pollutant accumulators.Moss bags can be used also in winter conditions and they provide more homogeneous and better controlled sampling method than snow samples.     

Heavy metals accumulation in tree leaves from urban areas

Higher plants may be used as biomonitors for the assessment of atmospheric heavy metal pollution by means of their bioaccumulative properties. We evaluated the reliability of biomonitoring heavy metal pollution by horse chestnut and linden leaves, common species found in Belgrade city parks. The results show that the highest concentrations of heavy metals were found in horse chestnut leaves at Studentski Park site, amounting to 110.2, 20.3 and 4.9 g g^–1 dry weight for Cu, Pb and Cd, respectively, which are considered above toxic levels for plants.Selected article from the Regional Symposium on Chemistry and Environment, Krusevac, Serbia, June 2003, organised by Dr. Branimir Jovancicevic.