Effect of epibionts on the microdistribution of chlorophyll in corals and its detection by fluorescence spectral imaging

The spatial distribution of chlorophyll in three coral species carrying invertebrate symbionts was determined using spectral imaging techniques. From each pixel of the image, full fluorescence spectral data was obtained as well as comparative ratios of fluorescence. The multipixel fluorescence map and the relative-intensity fluorescence ratios demonstrated a high concentration of chlorophyll a next to the pits of Cryptochirus coralliodytes in Favites halicora. Spectral similarity maps of Goniastrea retiformis infested with Lithophaga lessepsiana and of Millepora dichotoma infested with Savignium milleporum revealed relatively higher chlorophyll concentrations in these two corals next to the symbionts. We hypothesize that the invertebrate symbionts fertilize their immediate surroundings with their excreta, enhancing algal growth. The spectral analysis system used in this study made it possible to distinguish such changes by spatial quantitation of the fluorescence emitted from small surface areas.     

Correlated evolution of male and female testosterone profiles in birds and its consequences

Circulating levels of testosterone in adults have mainly evolved as a consequence of selection on males for increased levels, while levels of circulating testosterone in females may be an indirect consequence of selection on males. A review of the literature revealed that intense directional selection for high levels of circulating testosterone in birds is likely to be mainly due to direct selection on males. A comparative study of testosterone levels in birds revealed a strong positive relationship between peak testosterone levels in adult females and peak levels in males. The slope of this relationship was significantly less than unity, implying that the testosterone levels in females have been reduced in species with high levels in males. An analysis of the order of evolutionary events suggested that peak concentration of testosterone in females changed after peak concentrations of testosterone in males. Females in colonial species of birds had significantly higher circulating peak testosterone levels compared to females of solitary species, and relative levels after controlling for the effects of peak levels in males were also larger, suggesting that any costs of high testosterone levels in females are particularly likely in colonial birds. Direct selection on male circulating testosterone levels may increase the costs that females incur from high testosterone titers. For example, high female levels may negatively affect ovulation and laying and may also affect the levels of testosterone that females deposit in their eggs and hence the exposure of pre- and post-hatching offspring to testosterone. This in turn may affect not only offspring behavior, but also offspring development and the trade-offs between growth, development of immune function, and behavior in offspring.     

Cell-cell recognition system in gorgonians: description of the basic mechanism

A comparative investigation of the chemical composition of Thalassiosira antarctica var. antarctica vegetative and resting stages revealed C:N and C:chl a ratios to be lower in vegetative cells. These trends primarily reflect vegetative levels of C/cell below, and N/cell and chl a/cell levels above those of spores. There was a change in chemical composition with the initial formation of resting spores, and spores continued to modify their composition while maintained in a cyclic light/dark regime for about one and one half weeks. Most notable was a net increase in carbon and chlorophyll a per cell. Spores then subjected to darkness for over one week appeared to retain most of the carbon and chlorophyll a previously synthesized. These findings support the idea that resting spores enhance the survival capabilities of a species under adverse conditions.     

A new enzyme immunoassay for PCDD/F TEQ screening in environmental samples: comparison to micro-EROD assay and to chemical analysis.

A new Enzyme ImmunoAssay (EIA) for PCDD/F TEQ measurement in extracts of environmental samples was described. The bioassay TEQ which derived from EIA and EROD were compared with each other and with results from chemical analysis. For all environmental samples, the EROD-TEQ is higher than the value from chemical analysis. However, the EIA-TEQ is much more identical with the value from chemical analysis. Our results indicate that the EIA assay is a complementary method to the EROD assay and should be useful as a rapid and sensitive screening tool for environmental samples in many situations.     

Possible use of constructed wetland to remove selenocyanate,arsenic, and boron from electric utility wastewater

Wetland microcosms were used to evaluate the ability of constructed wetlands to remove extremely high concentrations of selenocyanate (SeCN-), arsenic (As), and boron (B) from wastewater generated by a coal gasification plant in Indiana. The wetland microcosms significantly reduced the concentrations of selenium (Se), As, B, and cyanide (CN) in the wastewater by 64%, 47%, 31%, and 30%, respectively. In terms of the mass of each contaminant, 79%, 67%, 57%, and 54% of the Se, As, B, and CN, respectively, loaded into the microcosms were removed from the wastewater. The primary sink for the retention of contaminants within the microcosms was the sediment, which accounted for 63%, 51%, and 36% of the Se, As, and B, respectively. Accumulation in plant tissues accounted for only 2-4%, while 3% of the Se was removed by biological volatilization to the atmosphere. Of the 14 plant species tested, cattail, Thalia, and rabbitfoot grass were highly tolerant of the contaminants and exhibited no growth retardation. Environmental toxicity testing with fathead minnow (Pimephales promelas) larvae confirmed that the water treated by the wetland microcosms was less toxic than untreated water. The data from the wetland microcosms support the view that constructed wetlands could be used to successfully reduce the toxicity of aqueous effluent contaminated with extremely high concentrations of SeCN-, As, and B, and that a pilot-scale wetland should therefore be constructed to test this in the field. Cattail, Thalia, and rabbitfoot grass would be suitable plant species to establish in such wetlands.     

Investigating the sources of the mutagenic activity found in a river using the Salmonella assay and different water extraction procedures

In the routine São Paulo state (Brazil) surface water quality-monitoring program, which includes the Salmonella microsome mutagenicity assay as one of its parameters, a river where water is taken and treated for drinking water purposes has repeatedly shown mutagenic activity. A textile dyeing facility employing azo-type dyes was the only identifiable source of mutagenic compounds. We extracted the river and drinking water samples with XAD4 at neutral and acidic pH and with blue rayon, which selectively adsorbs polycyclic compounds. We tested the industrial effluent, raw, and treated water and sediment samples with YG1041 and YG1042 and compared the results with the TA98 and TA100 strains. The elevated mutagenicity detected with YG-strains suggested that nitroaromatics and/or aromatic amines were causing the mutagenicity detected in the samples analyzed. Positive responses for the blue rayon extracts indicated that mutagenic polycyclic compounds were present in the water samples analyzed. The mutagen or mixture of mutagens present in the effluent and water samples cause mainly frameshift mutations and are positive with and without metabolic activation. The Salmonella assay combined with different extraction procedures proved to be very useful in the identification of the origin of the pollution and in the identification of the classes of chemical compounds causing the mutagenic activity in the river analyzed.     

Toxic effects of orimulsion on rainbow trout <Emphasis Type="Italic">oncorhynchus mykiss</Emphasis>

GOAL, SCOPE AND BACKGROUND: Orimulsion (stable emulsion of natural bitumen and water) is a new imported industrial fuel in Lithuania. No data on its toxicity to fish is freely available. The aim of this study was to investigate sensitivity of rainbow trout (Oncorhynchus mykiss) to acute and chronic toxicity of orimulsion and to estimate the Maximum Acceptable Toxicant Concentration (MATC) of orimulsion to fish. METHODS: Laboratory tests were conducted on rainbow trout in all stages of development (embryos, larvae, adults). Acute toxicity (96-hour duration) and long-term (28 or 60-day duration) tests evaluating the wide range spectrum of biological indices were performed under semi-static conditions. RESULTS AND DISCUSSION: Median lethal concentration (96-hour LC50) values and their 95% confidence intervals derived from the tests were: 0.1 (0.09-0.12) to embryos, 0.06 (0.05-0.07) to larvae and 2.22 (2.02-2.43) to adult fish, and 28-day LC50 to adult fish was found to be 0.26 (0.21-0.32) g/l of total orimulsion respectively. The acute toxicity of orimulsion to rainbow trout can be characterised by a narrow zone of toxic effect and a sharp boundary between lethal and sublethal concentrations. The lowest 'safe' or 'no-effect' concentration values of total orimulsion obtained in long-term tests were equal to 0.09 g/l to adult fish, 0.019 g/l to embryos, and 0.0017 g/l to larvae. Proposed value of 'application factor' for orimulsion was found to be equal to 0.03. Since orimulsion has the property to disperse in all water volume, its toxic effect on fish can be characterised by the combined effects of dispersion and water-soluble-fraction. CONCLUSIONS: Maximum Acceptable Toxicant Concentration (MATC) of 0.0017 g/l of total orimulsion to fish was derived from long-term tests based on the most sensitive parameter of rainbow trout larvae (relative mass increase at the end of the test). According to substance toxicity classification accepted for Lithuanian inland waters, orimulsion can be referred to substances of 'moderate' toxicity to fish. RECOMMENDATIONS AND OUTLOOK: For prediction and evaluation of toxic impact of orimulsion accident spills on fish, some recommendations should be given. Since orimulsion has the property to disperse in all water volume during short time periods, the amounts of both spilled orimulsion and polluted water should be ascertained. Once both parameters are known, the real concentration of orimulsion in the water body must be determined. Then this concentration must be compared with 'safe' concentration to fish. By use of 'application factor' 0.03, approximate MATC for other fish species can be estimated when only acute toxicity data (96-hour LC50 value) is available.     

Short-term responses of Oryzias latipes (Pisces: Adrianichthyidae) and Macrobrachium nipponense (Crustacea: Palaemonidae) to municipal and pharmaceutical waste water in Beijing, China: survival, behaviour, biochemical biomarkers

Whole effluent toxicity was assessed for the fish Oryzias latipes and the prawn Macrobrachium nipponense for 18 h in a dilution series (0-66%) of the inflow and effluent of a municipal waste water treatment plant as well as waste water from a teramycin producing pharmaceutical industry, before, during and after a pilot laboratory purification process. The waste waters caused acute toxicity as measured by inhibition of light emission in the luminiscent bacterium Vibrio qingaiensis sp. nov. (Q67). EROD and aryl hydrocarbon hydroxylase activity in in vitro carp liver-cells showed a dose-dependent toxic response to the municipal waste water. Behavioural responses and time-to-death of fish and prawn, recorded online with the "Multispecies Freshwater Biomonitor" proved to be concentration- and time-dependent sensitive toxicity indicators in both types of waste water. Behaviour changed stepwise from normal activity to (increased or decreased) activity to more time spent on ventilation and finally to increased morbidity at higher concentration and time of exposure. The municipal waste water treatment plant managed to reduce toxicity to bacteria (Q67), prawn and fish. The pharmaceutical waste water treatment process still has to be improved, in order to reduce toxicity for fish and prawn.     

Polychlorinated dibenzo-p-dioxins and dibenzofurans in paper making from a pulp mill in China

An extensive investigation on the input, formation and fate of PCDD/Fs in a pulp mill using reeds as raw materials in China was carried out. The main PCDD/Fs input in the production process came from reeds, which may be contaminated by PCDD/Fs from sodium pentachlorophenate to control snailborne schistosomiasis. High levels of I-TEQ in the products were observed.