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The quality of sewage sludge-based products, such as composts and growth media, is affected by the contamination of sewage sludge with, potentially, hundreds of different substances. Therefore, it is difficult to achieve the reliable environmental quality assessment of sewage sludge-based products solely based on chemical analysis. In the present work, we demonstrate the use of the kinetic luminescent bacteria test (ISO 21338) to evaluate acute toxicity and the Vitotox™ test to monitor genotoxicity of sewage sludge and composted sewages sludge. In addition, endocrine-disrupting and dioxin-like activity was studied using yeast-cell-based assays. The relative contribution of industrial waste water treated at the Waste Water Treatment Plants led to elevated concentrations of polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and polychlorinated dibenzo-p-dioxins and -furans (PCDD/F) in sewage sludge. The effect of elevated amounts of organic contaminants could also be identified with biotests able to demonstrate higher acute toxicity, genotoxicity, and potential for endocrine-disruptive properties. Additional extraction steps in kinetic luminescent bacteria test with DMSO and hexane increased the level of toxicity detected. Composting in a pilot-scale efficiently reduced the amounts of linear alkylbenzensulphonates (LASs), nonylphenols and nonylphenolethoxylates (NPE/NPs) and PAH with relative removal efficiencies of 84%, 61% and 56%. In addition, decrease in acute toxicity, genotoxicity and endocrorine-disrupting and dioxin-like activity during composting could be detected. However, the biotests did have limitations in accessing the ecotoxicity of test media rich with organic matter, such as sewage sludge and compost, and effects of sample characteristics on biotest organisms must be acknowledged. The compost matrix itself, however, which contained a high amount of nutrients, bark, and peat, reduced the sensitivity of the genotoxicity tests and yeast bioreporter assays.

Investigations of toxic effects of water samples from industrial plants and landfill effluents on bioluminescent bacteria were carried out. The results of a standardised bioassay (LUMIStox) were compared to chemical analytic data (heavy metal concentrations, COD, and BOD). A reduction of bioluminescent activity was observed in most of the samples. The degree of reduction showed good correlation with the concentrations of anorganic and organic pollutant indicators. The applicability of the luminescent bacteria bioassay for the evaluation of the ecotoxicological potential of these kinds of polluted effluents was demonstrated.

Publisher Summary The goal of ecotoxicity is to understand the concentration of chemicals at which organisms in the environment will be affected. For the acceptance of compostable polymers, it is important to develop appropriate testing methods and standards. Ecotoxicological assessments requires a plant growth test on the final compost using two higher plants. This chapter evaluates the various ecotoxicological assessments used on compostable polymers. Ecotoxicology is the study of the toxic effects of chemical and physical agents on all living organisms, especially on populations and communities within defined ecosystems. Standard ecotoxicity tests measure important physiological and ecologically relevant responses such as lethality, growth, and reproduction. The evaluation of the ecotoxicity of compostable polymers is an important issue to ensure that the produced compost is safe and causes no health hazards. Several ecotoxicity tests are used to assess the potential toxic activity against plant and animal life during their degradation and after they are degraded. The methods of the evaluation of the ecotoxicity of compostable polymer materials are mainly based on the use of plants, soil fauna (earthworms), aquatic fauna (Daphnia), algae (green algae), and microbes (luminescent bacteria).

Over the years several types of biocide-free antifouling paints have entered the market. The prohibition of biocidal antifouling paints in special areas of some European countries such as Sweden, Denmark and Germany has favoured the introduction of these paints to the market. Several types of biocide-free antifouling paints were subjected to bioassays and selected chemical analysis of leachate and incorporated substances. Both non-eroding coatings (silicones, fibre coats, epoxies, polyurethane, polyvinyl) and eroding coatings (SPCs, ablative) were tested to exclude the presence of active biocides and dangerous compounds. The paints were subjected to the luminescent bacteria test and the cypris larvae settlement assay, the latter delivering information on toxicity as well as on efficacy. The following chemical analyses of selected compounds of dry-film were performed:leaching-rate of organotin compounds from silicones and of nonylphenol and bisphenol A from epoxy and vinyl based coatings,concentration and leaching rate of selected organic compounds in polyurethane,concentration of heavy metals in eroding coatings. The results of the bioassays indicated that none of the coatings analysed contained leachable biocides. Nevertheless, some products contained or leached dangerous compounds. The analyses revealed leaching of nonylphenol (up to 74.7 ng/cm2/d after 48 h) and bisphenol A (up to 2.77 ng/cm2/d after 24 h) from epoxy resins used as substitutes for antifouling paints. The heavy metal, zinc, was measured in dry paint film in quantities up to 576 000 ppm in erodable coatings, not incorporated as a biocide but to control the rate of erosion. Values for TBT in silicone elutriates were mostly below the detection limit of 0.005 mg/kg. Values for DBT ranged between

Publisher Summary The bioluminescent bacteria comprise one of several groups of luminous organisms. Significant differences exist between the bioluminescence reactions of different organisms, including the structure and properties of the luciferases and substrates. Molecular oxygen is the only common feature of bioluminescence reactions, indicating that the luminescent systems in most organisms may have evolved independently. Luminescent bacteria are present in marine environment, freshwater, and terrestrial habitats. They can occur as free-living forms, saprophytes, commensal symbionts, parasites of animals, and specific light-organ symbionts. The luminescence produced by these bacteria, because of its inherent beauty and ease of detection, has attracted scientific attention. With the use of molecular approaches to study the luminescence systems of these bacteria, population biology, ecology, and molecular mechanisms of luminescence (lux) gene regulation can be studied. This chapter describes the current status of bioluminescent systems of luminous bacteria, emphasizing the biochemistry, lux gene organization, and the physiological and genetic regulation of lux gene expression. The effects of oxygen on luminescence illustrate the application of bacterial luminescence system as a sensor of specific molecules that affect metabolic function and gene expression. Knowledge of the basic biochemistry, molecular biology, and physiology of luminescent bacteria is thus not only of interest but of importance for future scientific endeavors.