Lead in the diet and body tissues of dunlins, Calidris alpina, from the Bristol Channel, UK

Lead concentrations were determined in the organs of a shorebird, the dunlin, in its main invertebrate prey, and in sediments collected from five sites in the Bristol Channel. The highest sediment concentrations were found in the Taff Estuary (97 microg g(-1) dry mass). The highest concentrations in invertebrates were found in the upper Severn Estuary (45 microg g(-1) dry mass in Nereis diversicolor). In dunlins, the highest concentrations were found in the sternum (25 microg g(-1) dry mass in males), followed by the beak, legs, kidney, liver and pectoral muscle. Adult males contained significantly higher concentrations (ca 20%) than adult females, and in some cases adults had significantly higher concentrations than first year birds (36% higher in the case of the sternum). Lead concentrations tended to increase throughout the winter, being 37-115% higher in the spring. Birds were able to purge themselves of a substantial portion of their body lead burdens, probably during the autumn moult.     

Qualitative and quantitative effects of ozone and/or sulfur dioxide on field-grown potato plants

Solanum tuberosum L. cv Norchip plants were grown in open-top chambers in the summer of 1986. Plants were treated with charcoal-filtered air, nonfiltered air, or nonfiltered air supplemented with 33, 66, or 99% of the ambient ozone (O3) concentrations from 1000 to 2000 h eastern daylight time daily. In addition, plants received charcoal-filtered air plus 0, 0.15 (393 microg m(-3)), 0.34 (891 microg m(-3)), or 0.61 (1598 microg m(-3)) ppm sulfur dioxide (SO2) from 0900 to 1200 h once every 14 d for a total of four treatments. Ozone induced a linear reduction in number and weight of Grade One (> 6.35-cm diameter) potato tubers and in total weight of tubers. Ozone also induced linear reductions in the percentage of dry matter of tubers and linear decreases in glucose and fructose content of Grade One tubers. Sulfur dioxide induced a stimulation and then decline of the number, percentage of dry matter, and sucrose content of Grade One tubers. The SO2 response best fit a quadratic curve. No O3 x SO2 interactions were detected for any of the yield or quality functions measured.     

Volatile organic compounds in the surface waters of northern Greece

An investigation into the occurrence of volatile organic compounds (VOCs) was conducted for a period of two years in the surface waters of Northern Greece. Samples from four rivers and five lakes were taken seasonally and analyzed for VOCs. The analysis has been performed by purge-and-trap (PAT) gas chromatographic-mass spectrometric (GC-MS) technique. The most commonly encountered VOCs in surface waters were chloroform, carbon tetrachloride, trichloroethylene, dichlorobromomethane, tetrachloroethylene, and chlorodibromomethane.     

Polychlorinated dibenzo-p-dioxins and dibenzofurans in sediment, soil, fish, shellfish and crab samples from Tokyo Bay area, Japan

Concentrations of tetra- to octa-chlorinated dibenzo-p-dioxins and dibenzofurans in samples collected in or near Tokyo Bay, Japan, with a densely inhabited catchment area, were congener-specifically determined and discussed. Analyzed in this study were samples of surface sediment covering the whole bay area, reference soil representing atmospheric impact, and fish, shellfish and crab commonly consumed as food. The range of concentrations were comparable to or higher than those in other parts of Japan. The origins of these compounds in the catchment area of the bay were investigated in terms of homolog and isomeric compositions in the sediment samples. Biota-sediment accumulation factors for benthic species declined as the degree of chlorination increased.     

Effects of five insecticides used in apple orchards on Hyaliodes vitripennis (Say) (Hemiptera: Miridae)

Azinphos-methyl, carbaryl, dimethoate, phosmet and phosalone were used in apple orchards to manage apple aphid, apple maggot, woolly apple aphid and leaf eating caterpillars. Among the five insecticides evaluated, dimethoate, carbaryl and azinphosmethyl were the most toxic to the nymphs and adults of Hyaliodes vitripennis (Say) from two regions. Phosalone was the least toxic. Nymphs were more resistant than the adults. While the LC50 for dimethoate was 130 ppm for nymphs, it was 3 ppm for adults from St. Jean-Baptiste-de-Rouville. There were also significant differences in the level of resistance between the two regions where the H. vitripennis were collected. At St. Alexandre the LC50 for phosalone on nymphs was 19,250 ppm whereas, at St. Jean-Baptiste-de-Rouville it was 160,000 ppm.     

Analysis and simulation of wintertime light scattering by the urban aerosol in Dallas-Fort Worth

Wintertime atmospheric light scattering in Dallas, TX, was estimated through the use of aerosol models. Input data for the aerosol models were provided by measurements of aerosol chemistry, physical particle size distributions, and distributions of particulate sulfur by particle size, and by predictions by an atmospheric simulation model. Light scattering measurements provided a basis for testing the aerosol models. The SCAPE thermodynamic equilibrium model was used to estimate the amount of liquid water associated with particles and the ELSIE Mie scattering model was applied to estimate the resulting light scattering. The calculations were based on aerosol properties measured in Dallas during December 1994 and February 1995, and changes in scattering due to hypothetical changes in the aerosol were predicted. The predicted light scattering was compared to scattering measured by an Optec nephelometer; agreement was within 20% in every case.     

Stratospheric ozone depletion, UV-B radiation and crop disease

Ultraviolet-B radiation (UV-B: 290-315 nm) is expected to increase as the result of stratospheric ozone depletion. Within the environmental range, UV-B effects on host plants appear to be largely a function of photomorphogenic responses, while effects on fungal pathogens may include both photomorphogenesis and damage. The effects of increased UV-B on plant-pathogen interactions has been studied in only a few pathosystems, and have used a wide range of techniques, making generalisations difficult. Increased UV-B after inoculation tends to reduce disease, perhaps due to direct damage to the pathogen, although responses vary markedly between and within pathogen species. Using Septoria tritici infection of wheat as a model system, it is suggested that even in a species that is inherently sensitive to UV-B, the effects of ozone depletion in the field are likely to be small compared with the effects of variation in UV-B due to season and varying cloud. Increased UV-B before inoculation causes a range of effects in different systems, but an increase in subsequent disease is a common response, perhaps due to changes in host surface properties or chemical composition. Although it seems unlikely that most crop diseases will be greatly affected by stratospheric ozone depletion within the limits currently expected, the lack of a detailed understanding of the mechanisms by which UV-B influences plant-pathogen interactions in most pathosystems is a significant limit to such predictions.     

Biodeterioration of cardboard-based liquid containers collected for fibre reuse

Liquid packaging board (LPB) collected in Germany is processed in Finland as recycled fibre and as plastic reject for incineration. The chemical, biological and physical changes occurring in recycled LPB bales were monitored during storage of six and 18 months. The moisture content in the core of the bales ranged from 7% to 53%, and pH values varied from 6.0 to 8.5. The average amount of mesophilic bacteria per container was 1.5 x 10(7) - 5 x 10(8), which means that recycled LPB pulp cannot be recommended for sanitary use. The concentration of CO2 inside the bale is an indicator of the activity of aerobic microorganisms and might be suitable for identifying deteriorated bales and removing them from the production line. Insects were found in some bales and the more deteriorated the bale was the more species of insects were found. The results showed the conversion of cellulose into humic acids to be clearly underway in some recycled LPB bales. The bale samples were extracted into hot water and into fulvic acids and humic acid (HA) fractions. The concentration of the humic acid fraction varied in the range 0.3-0.6% of the organic matter in fresh bales and 2.2% in one old bale. During aging nitrogen was enriched in all fractions.     

Off-site forensic determination of waterborne elemental emissions: a case study at a secondary lead smelter

A multi-element, multi-media analysis of waterborne sediments downstream from a secondary lead smelter is presented. Sediments were collected from a closed municipal storm water drain, an open private storm water conveyance, and a channelized river. Characteristic ratios of lead, antimony, arsenic, and cadmium were found in the samples, which were similar to air and soil samples taken at the same site. Additional elements, some associated with lead-acid batteries and some not, were also found. Significant correlation was found among the concentrations of the majority of these elements.     

Responses of indicator bacteria to forest soil amended with municipal sewage sludge from aerated and non-aerated ponds

The survival of faecal and total coliform bacteria and Streptococcus faecalis (indicator bacteria) were monitored in experimental plots receiving various amounts of biological or dephosphatation municipal sewage sludge. Biological sludge was applied on coniferous and mixed regenerative forest soils. The results show that except for total coliforms, there was little significant treatment effect on the indicator bacteria numbers in all of the sites. In most cases, there was a significant time effect, indicating that bacterial populations vary over time, according to environmental factors such as temperature, moisture or nutrient level conditions. In total coliform bacteria, populations varied over time but also in function of treatment levels. The present study suggests that even if the standards of Québec (Canada) for sludge application are respected, there may be some risk for bacterial contamination depending on the types of sewage sludge and forest habitat. Although there is only a short-term effect, high slopes can influence the movement of the indicator bacteria and may potentially cause some contamination problems.