Acute toxicity of olive mill wastewaters (traditional and continuous processes) collected from different regions of Portugal was evaluated using three test species (Vibrio fischeri formerly Photobacterium phosphoreum, Thamnocephalus platyurus, and Daphnia magna) and correlated with several physical and chemical parameters. Acute toxicity of these effluents, expressed in LC50 or EC50, ranged from: 0.16 to 1.24% in Microtox test, 0.73 to 12.54% in Thamnotoxkit F test, and 1.08 to 6.83% in Daphnia test. These values reflect the high toxicity of the olive mill wastewaters to all test species. Statistical analysis of the results shows a high correlation between the two microcrustacean bioassays. Microtox test did not correlate significantly with the other bioassays used. A significative correlation (p≤0.05) could also be established between L(E)C50 obtained in the microcrustacean tests and some physicochemical parameters of the effluent.  ©1999 John Wiley & Sons, Inc. Environ Toxicol 14: 263–269, 1999

The mycelium of Fusarium flocciferum was assayed for its ability to degrade aromatic compounds, namely, gallic, protocatechuic, vanillic, syringic, caffeic, and ferulic acids and syringic aldehyde, commonly found in agro-industrial wastes. The biodegradation assays were performed in liquid medium with the phenolic compounds as single substrates and as a synthetic mixture containing the seven aromatic compounds. The results with single substrates indicated that in 24 hrs of incubation the fungus was able to reduce the phenolic concentration from 200 mg/l to below detection limits, except for syringic acid, being the lowest degradation rates found for this acid and its aldehyde. The biodegradation experiments with the mixture of phenolic compounds showed that after 8 hrs the total phenolic concentration was reduce from 350 mg/l to below the detection limits of all the tested compounds. In all the experiments a rise in the pH and an effective detoxification of the phenolic solutions were also observed.

The ability of several fungal strains to degrade and to detoxify cork boiling wastewaters was investigated. The fungal strains used in this work were Sporothrix sp., Trichoderma koningii, Chrysonilia sitophila and Penicillium glabrum isolated from cork bark as well as Fusarium flocciferum and Phanerochaete chrysosporium. The results obtained in the degradation experiments carried out with each fungus showed that all fungi display similar abilities, with a chemical oxygen demand reduction of 54.2 % (± 4.7 %) attained within five days of incubation. F. flocciferum presented the highest value for the reduction of chemical oxygen demand of 62 %. In addition, a rise in pH values of around 3 units was detected with all the strains, except for Penicillium glabrum. Toxicity tests performed on Vibrio fischeri revealed that fungal treatment of the wastewaters causes the complete loss of toxicity in the cases of Sporothrix sp., T. koningii, P. chrysosporium and F. flocciferum. The other two tested strains were also able to detoxify the raw wastewaters, causing a ten‐fold decrease in toxicity. The results obtained in sequential biodegradation experiments with different pairs of fungi showed that although the increment in the COD reduction did not exceed 10 %, an important reduction in toxicity and a pH rise were attained.

The biosorption capacity of dead biomass of Fusarium flocciferum for copper (Cu), cadmium (Cd), and nickel (Ni) was studied with the aim of developing the basis for an industrial effluent treatment. It was verified that a Langmuir isotherm describes well the biosorption of cadmium and nickel, whereas copper showed a more irregular behavior. Estimated maximum uptake, Qmax expressed as mg metal/100 mg biosorbent, was 19.2 for cadmium and 5.2 for nickel. Maximum reproducible values for copper biosorption were between 4 and 6 mg/100 mg. In this case, it was verified that process efficiency depends on the balance between biosorbent and metal initial concentrations. Studies with different contact times showed that the process was completed within a few minutes. No difference in biosorbent metal affinity was found for cell incubation periods ranging from 24 hours to 4 days, but the biosorbent obtained from older cultures showed a decrease in metal removal capacity. This biosorbent is prepared from a fast‐growing fungus with low nutritional and physical requirements. It can be used to remove metals from very dilute solutions at neutral pH values, as in the final steps of heavy metal removal from industrial wastewaters.

Tributyltin (TBT) is one of the most toxic xenobiotics ubiquitous in