Persistent organochlorines in beluga whales (Delphinapterus leucas) from the St Lawrence River estuary--II. Temporal trends, 1982-1994

Blubber samples from 16 dead beluga whales (Delphinapterus leucas) collected during 1993-1994 in the St Lawrence River estuary were analysed for PCB congeners and other persistent organochlorines (DDT-group, chlorinated bornanes (toxaphene, CHB), chlordane SigmaCHL), hexachloro-cyclohexanes (SigmaHCH), chlorobenzenes (SigmaCBz), tris(p-chlorophenyl methane (TPMe) and mirex). Concentrations and relative proportions of major individual organochlorine components were within the same range as previous results for this population. Temporal trends were studied by combining the results with data from the analysis of 44 samples (1986-1990) and (for DDT and Aroclor PCBs only) with 20 samples (1982-1985) reported by Martineau et al., 1987. Results were lipid normalized and then age-adjusted by an ANCOVA model. Significant relationships between age and concentrations of most organochlorine groups were found for females but not for males. Significant declines were observed in SigmaDDT, and Aroclor PCBs (1.5- and 1.9-fold, respectively) in males between the 1982-1985 and 1993-1994 collection periods. Significant declines were also observed for SigmaHCH and SigmaCBz in males between 1986-1988 and 1993-1994. Mean concentrations of CHBs were significantly higher in 1993-1994 than in earlier years while dieldrin, SigmaCHL, mirex, and TPMe showed no trend. Declines in concentrations of major organochlorine groups were not observed in females possibly because of higher year to year, and within year, variation. The temporal trend in DDT and PCB concentrations in male beluga blubber paralleled trends in seals, eels, and seabirds in the St Lawrence estuary observed during the 1980s.     

The monitoring of cadmium,zinc and copper in the kidneys and liver of humans deceased in the region of Cracow (Poland)

Cadmium, zinc and copper levels were determined in the renal cortex and liver of 60 inhabitants of Cracow, Poland. Cadmium levels in the renal cortex were contained in broad limits of 5–176 g/g, mean 50.6 g/g (wet weight). Maximum levels were found in the age group of about 50–60 years. The levels were slightly higher in men (53 g/g) than in women (45 g/g), with no effect of location within the region. The levels in smokers (62 g/g) were much higher than in non-smokers (32 g/g). The above relations were less pronounced for cadmium levels in the liver. Whole body retention of cadmium followed the pattern of cadmium in renal cortex. The level of zinc in renal cortex reflected those of cadmium. A significant proportion of the population (54% in smokers, 9% in non-smokers) showed cadmium levels in renal cortex exceeding the reference level of 50 g/g recently accepted for general population. In the view of the authors the exposure to cadmium of the population of Cracow is excessive and calls for attention.The study was performed under a KBN grant No 40106 91 01.     

Long-term trends and sources of organochlorine contamination in Canadian tundra Peregrine Falcons, Falco peregrinus tundrius

Levels of eggshell thinning, and organochlorine residues in egg contents, blood plasma of adults and juveniles, tissue samples, and prey species were determined for a population of migratory Peregrine Falcons (Falco peregrinus tundrius) breeding in the Canadian Arctic. Temporal trends were assessed by comparing data collected during 1991-1994, with data from 1982-1986, for the same population. Shells (n=54) from 1991-1994 averaged 15% thinner than eggs produced prior to the introduction of DDT. No improvement in shell thickness was detected between decades. Mean DDE residue levels in eggs showed a decline from 7.6 mg kg (1982-1986) to 4.5 mg kg (1991-1994), but there was no significant change in SigmaPCB residues. Moreover, the proportion of clutches with eggs exceeding critical SigmaPCB, DDE, and dieldrin residue levels (10%) did not change between decades. Relative to Greenland and Alaskan populations, F. p. tundrius at Rankin Inlet show high levels of organochlorine contamination and little reduction in residues over the last decade. These Tundra Peregrines continue to be exposed to organochlorines in Latin America; however, results also link relatively high levels in the study population with waterfowl species that do not leave Canada in winter.     

Fluorosis - a case study from the Sambher Salt Lake region in Jaipur, Rajasthan, India

Assistant Professor in Human Ecology, in the Indira Gandhi Centre for Human Ecology, Environment and Population Studies at the University of Rajasthan. Although fluorine is an essential element for human growth and development, its intake in excessive amounts beyond the permissible limits can be very harmful. Dental and skeletal fluorosis are some of the common afflictions of fluorine poisoning and it can even have crippling effects in aged individuals. With the rise in industrialization fluoride contamination is increasing in the human environment as it is a basic component of the ground water. Certain regions of India, particularly the arid zones of Rajasthan, have serious fluoride problems and it has become a serious health hazard in several villages of Rajasthan.     

Effects of the insect growth regulator (S)-methoprene on survival and reproduction of the freshwater cladoceran Moina macrocopa

This study examines the acute and chronic effects of the insecticide (S)-methoprene on the survival and reproduction of the freshwater cladoceran Moina macrocopa. In laboratory toxicity tests, the 24- and 48-h LC50 values for (S)-methoprene were 0.51 and 0.34 mg litre(-1), respectively. Survival, longevity and fecundity were reduced at 0.05 mg litre(-1) and higher concentrations. At 0.005 and 0.01 mg litre(-1), longevity and fecundity increased slightly as compared to control animals. If environmental concentrations of methoprene do not exceed 0.05 mg litre(-1), as is generally the case, application of this insecticide is unlikely to induce detrimental effects on natural cladoceran populations. The stimulatory effect of very low levels of methoprene on reproductive performance is consistent with the hypothesis of a regulatory role of juvenile hormone-like compounds in crustacean reproduction.     

Biomonitoring environmental contaminants near a municipal solid-waste combustor

Tetrachlorodibenzo-p-dioxin (TCDD), tetrachlorodibenzofuran (TCDF) and selected metal concentrations were measured in eggs and nestlings of anhingas (Anhinga anhinga) and white ibises (Eudocimus albus) collected from a colony next to a municipal solid-waste (MSW) combustor and ash landfill. Most of the measured residues, including TCDD, TCDF, arsenic, beryllium, cadmium and nickel, remained at pre-operational levels during the first five years of facility operation. Selenium (in anhingas) and mercury (in both anhingas and ibises) occurred at their lowest concentrations in samples collected during the fifth year of facility operation (Year-5). Alternatively, concentrations of lead in ibis nestlings were highest in Year-1 and Year-5 compared to Year-0. The MSW combustor could neither be ruled out nor confirmed as the source of this lead.     

The influence of particle surface characteristics on pollutant metal uptake by cells

The phosphatic mineral, hydroxyapatite, and two ion exchange resins have been used as artificial sediment particles. The surface properties of these materials have been studied using the Langmuir adsorption isotherm to calculate the binding capacity (B(max)) and the adsorption constant (K(L)) for zinc and cadmium ions. Mussels (Mytilus edulis) were fed on the particles and their digestive glands were subsequently removed and subjected to cell fractionation. The supernatant fraction was used to determine cytosol metal levels as a measure of the materials absorbed from the ingested particles. The level of cytosol zinc and cadmium was correlated with the K(L) values of the artificial sediments. It is suggested that phagocytosis of sediment particles plays an important part in transferring pollutants into benthic organisms and that the efficiency of this process is related to the adsorption coefficient of the particle surfaces.     

Book reviews

Rebuilding the City: Property‐led Urban Regeneration

P. Healey, S. Davoudi, M. O'Toole, S. Tavsanoglu & D. Usher (Eds)

London, E. & F. N. Spon, 1992, 312 pp., £30

Der Wert stadtnaher Wälder als Erholungsraum: Eine ökonomishce Analyse am Beispiel von Lugano (Value of Urban Forests as Recreational Areas: An Economic Analysis on the Case of Lugano)

Claudia Nielsen

Chur (Switzerland), Verlag Rüegger, 1992, 261 pp., SFr 48

Urban Planning under Thatcherism: The Challenge of the Market

A. Thornley

London, Routledge, 1991, 253 pp., £14.99

Sustainable Development and Urban Form, European Research in Regional Science 2

M. J. Breheny (Ed)

London, Pion, Limited, 1992, 292 pp., £28.00.

Tourism, Museums and the Local Economy: The Economic Impact of the North of England Open Air Musuem at Beamish

Peter Johnson & Barry Thomas

Cheltenham, Edward Elgar, 1992, 160 pp., £29.50     

Effects of air pollutants on the growth and antioxidative system of Norway spruce exposed in open-top chambers

Grafted Norway spruce trees were subjected to exposure beginning in April 1988, to one of four different air treatments in open-top chambers: Charcoal filtered air (CF), non-filtered air (NF), non-filtered air with the addition of O(3) during summer (NFO), and SO(2) plus NO(2) during winter (NFOSN). CF trees were considered as the reference group. No effects on growth parameters were observed. Samples of the two youngest needle year classes were taken late in November 1989 for enzyme determinations. The activity of ascorbic acid peroxidase (A-POD) increased the same level in all treatments, and activities of catalase and dehydroascorbic acid reductase (DHA-R) increased only in NF and NFO treatments. A higher level of activity in the NFOSN treatment was observed only for glucose-6-phosphate-dehydrogenase (Glc-6-P-DH) and non-specific peroxidase (POD). Isoelectric focusing of POD showed a changed pattern in the NFOSN treatment. Neither activity nor isoelectric focusing of superoxidase dismutase (SOD) was changed in any of the treatments.     

The fate of endosulfan in aquatic ecosystems

Endosulfan, one of the major pesticides used in cotton-growing, is of environmental concern because of its toxicity to fish and its apparent persistence in the environment. This study examines the distribution and degradation pathways for endosulfan in an aquatic system and the processes by which it is removed. In the alkaline waters of the cotton region, hydrolysis is the dominant degradation process. By this mechanism alone, the expected half-lives for the alpha- and beta-endosulfan isomers were found to be 3.6 days and 1.7 days, respectively. Partitioning studies showed, however, that the major proportion of endosulfan would associate with the sediments (log Koc(alpha) 3.6 and log Koc(beta) 4.3). Field studies confirmed the presence of high concentrations in sediments. Microcosm experiments showed that loss of endosulfan was slower than predicted from hydrolysis rates. Models are presented to explain how desorption from sediment limits the loss of endosulfan from a system.