Base cation (Ca, Mg, Na, K) concentrations in surface waters, pore waters and surface peats were determined along a mineral-poor to mineral-rich fen gradient for 15 south-central Ontario peatlands. Surface waters of the peatlands ranged in pH and alkalinity from 4.5 to 6.3 and 0 to 181 μeqL⁻¹, respectively. Both surface water and pore water Ca and Mg concentrations followed the expected decrease along the mineral-rich to poor-fen gradient. Surface water concentrations of Ca and Mg were significantly lower in the mineral-poor versus the moderately-poor and mineral-rich fens (P <0.05, ANOVA). Pore water concentrations of base cations were 3–5 fold less in mineral-poor vs. mineral-rich fens. In contrast to surface and pore waters, peat base cation concentrations did not decrease along the mineral-rich to mineral-poor fen gradient. Surface peat base cation concentrations were also independent of pore water cation concentrations, and local bedrock geology. Relative concentrations of base cations in surface peats of all peatlands were best described by the exchangeable cation capacity of the surrounding soils.

The anaerobic conditions in landfill leachate-polluted aquifers can lead to trapping of many heavy metals as sulfide precipitates. In laboratory experiments with aqueous systems containing sulfidic solid phases (aquifer solids from a landfill leachate plume or amorphous FeS), cadmium previously trapped as a sulfide precipitate was released to the aqueous phase when conditions were changed from initially slightly anaerobic to aerobic. Cadmium was subsequently removed from solution either by adsorption on Fe oxyhydroxide phases or by precipitation as a carbonate mineral, groundwater pH being the major controlling variable.

The concentrations of As, Br and I were measured in needles, in the material deposited on the needle surface and in the soil. Results from 8 unpolluted and one polluted continental sites and from one maritime site are reported. The mass of al13 elements on the needle surface is similar to that in the needles. Needle concentrations increase linearly with the needle age class, but net accumulation during the first year is larger than during later years. There are significant correlations between the material on the needle surface and the needle concentrations for As and Br, but not between the soil and the needle concentrations. Bromine values are much higher at the polluted and at the maritime site than at the unpolluted sites.

Sediments from 8 river mouths of the Catalonian coast (Spain) were examined for keratinolytic fungi. Out of 1250 river and marine samples examined, 499 (39.9%) were positive for these fungi. Aphanoascus fulvescens (anamorph + teleomorph), Chrysosporium keratinophilum, Ch. tropicum, Ch. an. of Arthroderma curreyi, Ch. pannicola, Ch. europae and Ch. indicum were the predominant species in the sediments. River samples were rich in keratinolytic fungi, whereas in marine beach sediments they occurred sporadically. The results of a preliminary experiment demonstrated that, marine water exerted a dramatical impact on river keratinolytic fungi causing their total or near-total elimination. The qualitative and quantitative compositions of river keratinolytic mycoflora depended on the degree of water contamination with sewage and on natural factors (mainly temperature). The keratinolytic mycoflora of two rivers was possibly altered dramatically by water contaminants, including poisons of industrial origin, and marine salinity. The problem of public health risk resulting from the distribution of keratinolytic fungi within the highly-frequented recreational waters is discussed.

In view of the toxic nature of Beryllium and its compounds the disposal of waste materials containing beryllium needs prior evaluation. The present study was undertaken to obtain information on the leachability and immobilisation of beryllium from solid waste red-mud generated in processing Beryl at the Beryllium Metal Plant at Vashi, New Bombay. The studies showed that 62% of the total beryllium in red-mud can be extracted by water by repeated leaching over a period of 445 d. The mixing of the waste material with cement and casting into cement blocks reduced the leachability of beryllium to 0.11% which got further reduced to 0.02% by thermal curing of cement blocks.

A total of 51 lakes in southern Quebec, Canada, were sampled between 1985 and 1993 to study changes in water chemistry following reductions in SO₂ emissions (main precursor of acid precipitation). Time series analysis of precipitation chemistry revealed significant reductions in concentrations and deposition of SO₄ ²⁻ from 1981 to 1992 in southern Quebec as well as reductions in concentrations and deposition of base cations (Ca²⁺, Mg²⁺), NO₃ ⁻ and H⁺ in the western section of the study area. Reductions in atmospheric inputs inputs of SO₄ ²⁻ have resulted in decreased lakewater SO₄ ²⁻ concentrations in the majority of the lakes in our study, although only a small fraction (9 of 37 lakes used in the temporal analysis) have improved significantly in terms of acidity status (pH, acid neutralizing capacity — ANC). The main response of the lakes to decreased SO₄ ²⁻ is a decrease in base cations (Ca²⁺+Mg²⁺), which was observed in 17 of 37 lakes. Seventeen lakes also showed significant increases in dissolved organic carbon (DOC) over the period of study. The resulting increases in organic acidity as well as the decrease in base cations could both play a role in delaying the recovery of our lakes.

Virus detection in drinking water is very important to protect human health. The different methodologies for analysing human pathogenic virus are very time consuming and expensive, so until now only a few specialised laboratories carried out this analysis. Detection of bacteriophages may be possible by examining the aquatic virus, with advantages of easy and cheap. The bacteriophages ofBacteroides fragilis have been proven as specifically present in human faeces and have relationships with water contaminated by enterovirus. Our study, for the first time in France, discovered theB. fragilis phages present in sample of sewage, Seine river and raw water for water supply. Our results also presented thatB. fragilis phages may be a better indicator for water bacteriology compared with classical bacteriological indicators in water treatment. On the other hand, our results demonstrated that MPN method (Most Probable Number) has more advantages than that of PFU (Plaque Forming Units).

Certain blood morphology parameters: red blood cell (RBC) sizes; percentage of polymorphonuclear leukocytes and ratio polychromatocyte/RBC in Brown trout (Salmo trutta L.) from acidified water (mean pH value 4.94) and limed water (mean pH value 5.66) were investigated. The sizes of RBC long axises were significantly larger in fish from acidic environment than from limed condition (14.37 and 12.96μm respectively). The percentage of polymorphonuclear cells (7.86 and 3.32) and polychromatocyte/RBC ratio (0.079 and 0.019) were also significantly larger in fish from the acidified environment. Blood morphology parameters are concluded to be usefull for testing and detection of long-term acidic stress in fish in nature.

Distributions of Mn, Zn, Cu, Ni, Cr, Pb, As, and Cd in Finnish surface waters were studied by comparing two data sets: samples from 154 headwater lakes collected by the Water and Environment Administration in 1992 and samples from 1165 headwater streams collected during the environmental geochemical mapping program of the Geological Survey of Finland in 1990. It was expected that headwater lakes with catchments smaller than 1 km²; and high lake percentage (ratio of lake area to catchment size) would be more influenced by atmospheric trace metal deposition than the streams, with average catchment size of 30 km²;.The lakes with highest arsenic concentrations lie in an area with greenstones and arsenic-rich black schists. The same lakes have high copper concentrations, which evidently are derived from the Cu-rich greenstones of the catchment. The high copper concentrations of streams and lakes in the industrialized region of the southwest coast are due to several anthropogenic sources.The highest concentrations of chromium occur in brown stream and lake waters rich in humic matter, while manganese and zinc concentrations, which are controlled by acidity, tend to be elevated in low-pH waters. The high nickel concentrations in lakes in southwestern Finland probably are due to anthropogenic input, while Ni anomalies in stream and lake water in eastern Finland are correlated with high Ni contents of glacial till. The lead concentrations in lakes are mainly of airborne anthropogenic origin.The pattern of atmospheric deposition is reflected in the concentrations of Cd, As, Cu, Zn, and Ni in headwater lakes, but land-use, the natural distribution of metals in the overburden, water acidity, and the amount of humic substances influence the distribution of trace metals in both lakes and streams. Thus the trace metal distribution in headwater lakes cannot be used alone to estimate the contribution of anthropogenic atmospheric deposition to metal anomalies in Finnish surface waters.

A greenhouse experiment using soil was conducted to investigate the effects of the addition of different forms of either nickel or lead, together with an acidifying agent, on the distribution of Ni, Pb, Zn, Cu and Mn in wheat plants, and on the post-harvest extractability of these elements in the soil. Two treatments consisting of soil alone or soil mixed with sewage sludge at a rate of 200 Mg ha⁻¹ were used as controls. Nickel (400 mg kg⁻¹) or lead (1600 mg kg⁻¹) was added to the soil as an inorganic salt or mixed previously with sewage sludge. Six further treatments including an acidifying agent (wastewater from olive oil processing: alpechin) were also prepared. Wheat (Triticum aestivum L. var. Mesa) plants were harvested 75 d after germination. Dry matter yield of wheat was increased by the addition of sewage sludge. No reductions in yield were observed after the addition of nickel or lead. Nickel concentration and uptake by wheat, and extractability from soil, were higher when the sewage sludge enriched in nickel was added to soil. This effect was enhanced when the acidifying agent was also added. In contrast, lead availability was higher after the addition of inorganic Pb to soil. The addition of both forms of Ni enhanced Zn, Cu and Mn uptake by the plant, whereas the addition of lead increased Zn and Cu. After harvesting, increases in extractable Zn and Cu in the soil were observed only in treatments with sewage sludge, and not after the addition of Ni or Pb, or after the addition of the acidifying agent. Decreasing the pH of the soil with the acidifying agent tended to increase Mn uptake by wheat, and Mn extractability from the soil after harvesting.