Variation of leaf gland volatile oil within a population of sweet gale (Myrica gale) (Myricaceae)

Summary The leaf gland volatile oils of ten sweet gale plants from a Scottish population were extracted in early summer. The results differed notably from reports of other populations in respect of the sesquiterpenes, -elemenone and germacrone, which were major components of the volatile oil. Three dihydrochalcones were also detected in the volatile oil. Variation within the population existed, particularly with respect to the relative importance of germacrone. Five plants were resampled in late summer and exhibited a marked reduction in -elemenone, a lesser reduction in germacrone and changes in the proportions of some monoterpenes.     

Development of a diffusive sampling method for determination of methyl isocyanate in air

A diffusive sampling method for determination of methyl isocyanate in air has been developed. A glass fibre filter impregnated with 1-(2-methoxyphenyl)piperazine in a commercially available diffusive sampling device was used to collect methyl isocyanate and the derivative formed was analysed with LC-MS/MS. The sampling rate was determined to be 15.6 ml min(-1), with a relative standard deviation of 7.3%. The sampler was validated for sampling periods from 15 min to 8 h, for relative humidities from 20% to 80% and for concentrations from I to 46 microg m(-3). A field validation was also made and the diffusive sampling results showed no difference compared to a pumped reference method. The impregnated filters have to be stored apart from the diffusive sampler housing and loaded into the sampler prior to each sampling.     

Development and validation of methods for environmental monitoring of cyclophosphamide in workplaces

Methods to monitor contamination of workplaces with antineoplastic drugs have been developed and validated. Cyclophosphamide (CP) was used as a model compound as it is one of the most commonly used antineoplastic drugs. A wipe sampling method to detect contamination with CP at surfaces was developed. A personal air sampling method to sample gas and vapour on solid sorbent tubes and particles with filters was also developed. Wipe and filter samples were extracted and sorbent samples were eluted, all with ethyl acetate. The samples were analysed with liquid chromatography tandem mass spectrometry. (2)H(6)-labelled cyclophosphamide was used as an internal standard. The between-day precision was 2-5% for wipe samples, 4-6% for sorbent samples and 3-8% for filter samples. The limit of detection was 0.02 ng CP per sample for the wipe and filter methods and 0.03 ng CP per sample for the solid sorbent method. Wipe sampling on surfaces made of different materials resulted in mean recoveries between 78-106%. The desorption recovery was between 97-102% for the wipe samples, 97% for the sorbent samples and 101% for the filter samples. Samples were stable for up to 2 months at 5 degrees C and -20 degrees C and for about 2 d at room temperature. The developed methods were applied to the measurement of contamination with CP in a hospital pharmacy. Trace amounts of CP, 1.3 and 1.4 ng, were detected on surfaces in the pharmacy.     

Bioindicator organisms: Heavy metal pollution evaluation in the Ionian Sea (Mediterranean Sea—Italy)

Trace metal concentrations of mercury, cadmium, lead and chromium in Patella caerulea, and Mullus barbatus were investigated to provide information on pollution of Ionian Sea, since these metals have the highest toxic potential. High chromium levels (0.47–0.97 g g^–1 ww) were registered in limpet samples collected from two station near the Gulf of Taranto, while elevated concentration of mercury (0.31–1.50 g g^–1 ww) were found in mullet specimens from Sicily. The metal concentrations recorded at the clean stations may be considered as useful background levels to which to refer for comparison within the Mediterranean area. On the contrary, the high levels of chromium and mercury found respectively in the areas near the Gulf of Taranto and at Capo Passero being of concern in terms of environmental health need frequent monitoring.     

Sulphate, Nitrogen and Base Cation Budgets at 21 Forested Catchments in Canada, the United States and Europe

To assess the concern over declining base cation levels in forest soils caused by acid deposition, input-output budgets (1990s average) for sulphate (SO₄), inorganic nitrogen (NO₃-N; NH₄-N), calcium (Ca), magnesium (Mg) and potassium (K) were synthesised for 21 forested catchments from 17 regions in Canada, the United States and Europe. Trend analysis was conducted on monthly ion concentrations in deposition and runoff when more than 9 years of data were available (14 regions, 17 sites). Annual average SO₄ deposition during the 1990s ranged between 7.3 and 28.4 kg ha⁻¹ per year, and inorganic nitrogen (N) deposition was between 2.8 and 13.8 kg ha⁻¹ per year, of which 41–67% was nitrate (NO₃-N). Over the period of record, SO₄ concentration in deposition decreased in 13/14 (13 out of 14 total) regions and SO₄ in runoff decreased at 14/17 catchments. In contrast, NO₃-N concentrations in deposition decreased in only 1/14 regions, while NH₄-N concentration patterns varied; increasing at 3/14 regions and decreasing at 2/14 regions. Nitrate concentrations in runoff decreased at 4/17 catchments and increased at only 1 site, whereas runoff levels of NH₄-N increased at 5/17 catchments. Decreasing trends in deposition were also recorded for Ca, Mg, and K at many of the catchments and on an equivalent basis, accounted for up to 131% (median 22%) of the decrease in acid anion deposition. Base cation concentrations in streams generally declined over time, with significant decreases in Ca, Mg and K occurring at 8, 9 and 7 of 17 sites respectively, which accounted for up to 133% (median 48%) of the decrease in acid anion concentration. Sulphate export exceeded input at 18/21 catchments, likely due to dry deposition and/or internal sources. The majority of N in deposition (31–100%; median 94%) was retained in the catchments, although there was a tendency for greater NO₃-N leaching at sites receiving higher (<7 kg ha^-1 per year) bulk inorganic N deposition. Mass balance calculations show that export of Ca and Mg in runoff exceeds input at all 21 catchments, but K export only exceeds input at 16/21 sites. Estimates of base cation weathering were available for 18 sites. When included in the mass balance calculation, Ca, Mg and K exports exceeded inputs at 14, 10 and 2 sites respectively. Annual Ca and Mg losses represent appreciable proportions of the current exchangeable soil Ca and Mg pools, although losses at some of the sites likely occur from weathering reactions beneath the rooting zone and there is considerable uncertainty associated with mineral weathering estimates. Critical loads for sulphur (S) and N, using a critical base cation to aluminium ratio of 10 in soil solution, are currently exceeded at 7 of the 18 sites with base cation weathering estimates. Despite reductions in SO₄ and H⁺ deposition, mass balance estimates indicate that acid deposition continues to acidify soils in many regions with losses of Ca and Mg of primary concern. The U.S. Government's right to retain a non-exclusive, royalty free licence in and to any copyright is acknowledged. The Canadian Crown reserves the right to retain a non-exclusive, royalty free licence in and to any copyright.     

Higher Plants As Bioindicators Of Sulphur Dioxide Emissions In Urban Environments

The evaluation of certain vascular plants that grow in the city of Madrid as biomonitors of SO₂ air pollution in urban environments has been carried out. Total concentration of sulphur in leaves of the chosen higher plants as well as other parameters in close relation to this contaminant (visible injury symptoms, chlorophyll a- and b-content and peroxidase activity) have been determined in order to study the spatial distribution and temporal changes in SO₂ deposition. Results obtained show that coniferous species such as Pinus pinea, were more sensitive to SO₂ atmospheric concentration than leafy species as Quercux ilex subspecies ballota and, in the same way, bush species, such asPyracantha coccinea and Nerium oleander, were more sensitive than wooded species, such as Cedrus deodaraandPinus pinea, respectively. There is a higher accumulation of sulphur in vegetable species located near highways and dense traffic incidence roads and near areas with high density of population. The minimum values for accumulation of SO₂ were registered in winter and spring seasons (from January to April) due to the vegetative stop; while maximum values are obtained during the summer season (from June to September), due to the stoma opening. The highest increments in sulphur concentration, calculated as the difference between two consecutive months, are obtained in May and June for all considered species except forCedrus deodara and Pyracantha coccinea, both species have few seasonal changes during the whole year. Some species are more sensitive to natural washing than others, showing a decrease in sulphur concentration after rainfall periods.     

Interlaboratory evaluation of endotoxin analyses in agricultural dusts--comparison of LAL assay and mass spectrometry

Endotoxin exposure is associated with wheeze and asthma morbidity, while early life exposure may reduce risk of allergy and asthma. Unfortunately, it is difficult to compare endotoxin results from different laboratories and environments. We undertook this study to determine if lipopolysaccharide (LPS) extraction efficiency could account for differences among laboratories. We generated and collected aerosols from chicken and swine barns, and corn processing. We randomly allocated side-by-side filter samples to five laboratories for Limulus assay of endotoxin. Lyophilized aliquots of filter extracts were analyzed for 3-hydroxy fatty acids (3-OHFAs) as a marker of LPS using gas chromatography-mass spectrometry. There were significant differences in endotoxin assay and GC-MS (LPS) results between laboratories for all dust types (p < 0.01). Patterns of differences between labs varied by dust type. Relationships between assay and GC/MS results also depended on dust type. The percentages of individual 3-OHFA chain lengths varied across labs (p < 0.0001) suggesting that each lab recovered a different fraction of the LPS available. The presence of large amounts of particle associated LPS and absence of a freezing thawing cycle were associated with lower correlations between LPS and bioactivity, consistent with an absence of Limulus response to cell-bound endotoxin. These data suggest that extraction methods affect endotoxin measurements. The LAL methods may be most suitable when comparing exposures within similar environments; GC-MS offers additional information helpful in optimizing sample treatment and extraction. GC-MS may be of use when comparing across heterogeneous environments and should be considered for inclusion in future studies of human health outcomes.     

Accumulation of metals in the soil of an overland flow wastewater treatment system

Accumulation of Co, Cu, Cr, Mo, Ni, Pb and Zn was evaluated in a soil profile of an overland flow system used for the post-treatment of urban wastewater. A pilot version of the overland flow system received urban wastewater from five up-flow anaerobic filters filled with bamboo (Bambusa tuldoides) rings. The anaerobic effluent was applied as feed over 18 months at rates varying from 7 to 28 L min(-1), to a vegetated slope length covered with Tifton 85 (Cynodon) sp. grass. Soil and plant samples were collected in triplicate from the top to the bottom of the slope. In addition, the soils were sampled at the depths 0-20 and 20-40 cm. The metal concentrations found in the overall system were compared to those obtained in a control area located at the beginning of the slope onto which nothing was applied. A month of monitoring the urban wastewater of Limeira City (S?o Paulo State, Brazil) showed a drastic change in metals concentration due to the irregular discharge of industrial waste. This irregular discharge introduces Cr, Cu, Ni, Pb and Zn into the system used to treat domestic wastewater. The mass balance indicates the accumulation of metals in the soil and the translocation to the plants; also that they could be evapotranspirated, percolated and discharged.     

Hydropower production and river rehabilitation: A case study on an alpine river

Despite the numerous benefits of hydropower production, this renewable energy source can have serious negative consequences on the environment. For example, dams act as barriers for the longitudinal migration of organisms and transport of particulate matter. Accelerated siltation processes in the receiving river reduce the vertical connectivity between river and groundwater. Hydropeaks, caused by short-term changes in hydropower operation, result in a negative impact on both habitat and organisms, especially during winter months when natural discharge is low and almost constant. In this study, we report the current deficits present in the River Rhone from two different scientific perspectives – fish ecology and hydrology. Potential rehabilitation solutions in synergy with flood protection measures are discussed. We focus on the effects of hydropeaking in relation to longitudinal and vertical dimensions and discuss local river widening as a potential rehabilitation tool. The fish fauna in the Rhone is characterized by a highly unnatural structure (low diversity, impaired age distribution). A high correlation between fish biomass and monotonous morphology (poor cover availability) was established. Tracer hydrology provided further details about the reduced permeability of the riverbank, revealing a high degree of siltation with K values of about 4.7 × 10^?6 m s^?1. Improving the hydrologic situation is therefore essential for the successful rehabilitation of the Rhone River. To this end, hydropeaks in the river reaches must be attenuated. This can be realized by a combination of different hard technical and soft operational measures such as retention reservoirs or slower up and down ramping of turbines.     

Indicators of ecosystem health at the species level and the example of selenium effects on fish

Chemical monitoring of aquatic ecosystems describes the chemical exposures of aquatic biota and measures the success of pollution control. However, meeting water quality criteria cannot assure that aquatic biota are protected from the effects of unexpected chemicals, mixtures and interactions between toxicity and environmental stressors.Biological monitoring is an obvious solution since aquatic biota integrate spatial and temporal variations in exposure to many simultaneous stressors. Top predators, typical of specific ecosystems (e.g. lake trout in cold water oligotrophic lakes) indicate whether environmental criteria have been met. The presence of naturally reproducing, self-sustaining and productive stocks of edible fish demonstrates a high quality environment. If these conditions are not met, there is a clear sign of environmental degradation. Specific changes in population structure and performance may also diagnose which life stage is affected and the nature of the stressor.Unfortunately, environmental managers cannot rely solely on populations, communities or ecosystems to indicate chmical effects. The lag between identifying a problem and finding a cause may destroy the resource that we wish to protect, particularly where chemicals are persistent.A solution to this dilemma is the measurement of primary or secondary responses of individual organisms to chemical exposure. Since toxicity at any level of organization must start with a reaction between a chemical and a biological substrate, these responses are the most sensitive and earliest sign of chemical exposure and effect.Application of this idea requires research on molecular mechanisms of chemical toxicity in aquatic biota and adaptation of existing mammalian diagnostic tools. Since relevance of biochemical responses to populations and ecosystems is not obvious, there is a need to study the links between chemical exposure and responses of individuals, populations and ecosystems.The recognition of chemical problems and cause-effect relationships requires the integration of chemical and biological monitoring, using the principles of epidemiology to test the strength of relationships and to identify specific research needs. The contamination of a reservoir with selenium and impacts on fish populations provide an excellent example of this approach.