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In this paper, the releasing characteristics and biological toxicity of Tl, Hg, As and Sb in waste of Lanmuchang mercury-thallium mine were studied. The results indicated that strong acidity can significantly promote the release of Tl from waste. With the increase of pH, the release of Sb grew steadily, while Hg and As showed a trend of first increasing and then decreasing. Fe2(SO4)3 contributed less to the release of As and Sb than to that of Hg and Tl. FeCl3 significantly inhibited the release of As, Sb and Tl. In the leaching experiments of litter and root exudates, the lixiviums appeared neutral, and the litter and root exudates solution significantly reduced the release of Tl, and showed less toxicity to luminescent bacteria. However, they promoted the release of Hg, As and Sb at different levels.

In this paper, toxicity values of alkylpolyglucosides have been determined by applying the 24-h immobilization test with Daphnia magna, the LumiStox(®) 300 test which employs the luminescent bacteria Photobacterium phosphoreum and the test with Selenastrum capricornutum. Three alkylpolyglucosides with different alkyl chain and degree of polymerisation have been tested. For all tests, the results indicated that Vibrio fischeri was more sensitive to toxic effects from alkylpolyglucosides than was D. magna or S. capricornutum. The results demonstrate considerable variation in toxicity responses within structurally related glucose-based surfactants regardless of the species tested. The toxicity increased as the critical micelle concentration decreased, and as the alkyl chain length and resultant hydrophobicity increased.

Acute toxicity (EC₅₀₋₃₀ min) and chronic toxicity (EC₅₀₋₂₄ h) of 21 antibiotics on Photobacterium phosphoreum was observed and Quantitative structure-activity relationship (QSAR) models were developed, respectively. By comparing these two QSAR models, the following model was established, log(1/EC₅₀₋₂₄ h) = 1.8283 + 1.1503log(1/EC ₅₀₋₃₀ min) + 0.2872Elomo - 0.0901DM + 0.0003PMIZ + 0.0088PSA - 0.0382SD, r² = 0.8513, where Elomo is lowest occupied molecular energy, DM is dipole moment, PMIZ is principal moment of inertia Z, PSA is polar surface area, and SD is sum of degrees. It provides a good way for us to obtain EC₅₀₋₂₄ h from EC₅₀₋₃₀ min, because the later is far easier to observe than the former.

Two short-term bacterial toxicity tests that have received a great deal of attention during the last few years are the Microtox and Spirillum volutans assays. The former involves monitoring changes in the light output from luminescent bacteria (Photobacterium phosphoreum) in a temperature controlled photometer when exposed to various concentrations of toxic substances. In the S. volutans assay, motility patterns of this large aquatic bacterium are used as the test endpoints. As part of the authors' program in assembling and establishing a battery of short-term bacterial toxicity tests, they examined the use of Microtox and S. volutans for determining the toxicity of a wide variety of environmental samples. Samples examined included potable and surface waters, industrial effluents, soil/sludge extracts and landfill leachates. Some of the results are presented in this paper.