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11.
B. N. Noller H. Bloom R. D. Dineen M. G. Johnson R. P. Hammond 《Environmental monitoring and assessment》1993,28(2):169-181
This study considers the effectiveness of the monitoring of toxic trace elements in various media from a polluted river estuary over a period of 15 years, using the same analytical techniques, facilities and, in some cases, the same operators. It shows that reliable comparisons can be made for monitoring waters, sediment and biota from the Derwent River Estuary between 1975 data and that from 1990. Rigorous studies were undertaken before and during 1975 to ensure that reliable data was achieved at that time. Such studies are reviewed and included the evaluation of digestion techniques for a range of heavy metals, specific attention to the reliability of mercury determination in sediments between laboratories, a comparison of direct calibration and standard addition techniques for metals in seawater, recoveries of an organomercury compound from fish, and sources of error arising from sample preparation of biota for subsequent metal analysis. Comparative results for standard reference materials in both 1975 and 1990 show good agreement and are considered reliable except for lead at low concentrations. The long-term retention of the analytical facilities permits a direct comparison of data from 2 monitoring programmes over the space of 15 years. 相似文献
12.
B. N. Noller 《Environmental monitoring and assessment》1991,19(1-3):383-400
Protection from the hazards from radioactivity is of prime importance in the management of uranium mine and mill wastes. Such wastes also contain non-radiological contaminants (heavy metals, acids and neutralising agents) which give rise to potential long-term health and environmental hazards and short-term hazards to the aquatic ecosystem, e.g. as a result of release of waste water. This study seeks to identify non-radiological contaminants (elements) transferred to waste water at the Ranger uranium mine/mill complex at Jabiru, which are likely to hazardous to the aquatic environment. The two principal sources of contaminants are:
- ore and waste rock mobilised from mining; and
- process reagents used in the milling and mineral extraction process.
13.
Violet Diacomanolis Barry N. Noller Jack C. Ng 《Environmental geochemistry and health》2013,35(6):757-766
Arsenic (As) and lead (Pb) are common contaminants found in mine waste materials. For an evidence-based risk assessment, it is important to better understand the potential interaction of mixed contaminants; and this interaction study was investigated in an in vivo rat model. Following co-administration of a fixed dose of AsV as in sodium arsenate and different doses of Pb as lead acetate to Sprague–Dawley rats, blood arsenic concentration and bioavailability decreased. A decrease in As blood concentration when lead was co-administered was observed with increasing lead doses. Pharmacokinetic parameters for As in the blood showed faster absorption and elimination of this metalloid in the presence of Pb. The elimination half-life of As decreased from 67 days in As solo group to 27–30 with doses of Pb. Bioavailability of As was also decreased by 30–43 % in the presence of Pb. Decreased urinary excretion of Pb and tissue accumulation were also observed. It indicates lower absorption of As when co-administered with Pb. A probable explanation for these findings is that As co-administration with Pb could have resulted in the formation of less soluble lead arsenate. However, such an interaction between As and Pb could only explain about one-third of the variation when real mine waste materials containing both of these elements were administered to rats. This suggests that other effects from physical and chemical parameters could contribute to the bioavailability of arsenic in complex real environmental samples. 相似文献
14.
Ecotoxicological assessment of diffuse pollution using biomonitoring tool for sustainable land use in Thailand 总被引:1,自引:1,他引:0
As a developing country, Thailand has a significant issue with diffuse pollution of the soil ecosystem due to an indiscriminate use of agrichemicals and poorly regulated disposal of a wide variety of hazardous wastes. Practical risk assessment tools based on locally-occurring species are needed to assess the effects of diffuse pollutants on the soil ecosystem in Thailand because reliance on soil criteria developed for overseas conditions may provide inadequate protection. Native soil organisms in Thailand may be more or less sensitive to contaminants compared to overseas test species. This article described a biological indicator approach for ecological risk assessment of diffuse pollution in the soil ecosystem of Thailand from pesticide application with the aim of developing standardized protocols using native species and locally generated data to better evaluate the ecological risks of non-point source soil pollution. It was found that ecotoxicological assessment provided a better understanding of the ecological impacts that diffuse pollution induced on Thai environmental conditions. Thai soil biota species were more sensitive to soil contaminants than similar species overseas. Soil series also had an influence on the ecotoxicology of contaminants to soil biota. Collembolan, Cyphoderus sp., was demonstrated as a useful alternative test species to Folsomia Candida (international test species) for terrestrial ecotoxicological testing of Thai soils. In addition, the soil biota activities such as soil respiration and earthworm avoidance including soil biodiversity and the litter bag decomposition technique are also good tools to assess the effects of diffuse pollution by pesticides on the soil ecosystem of Thailand. 相似文献