"Assessment of synergistic and antagonistic e!ects is not possible using chemical data. For proper assessment of polluted soils and monitoring of cleanup processes , toxicity data, chemical analysis, and ecological information should be combined (Plotkin and Ram, 1984; Linder et al., 1992; Schrab et al., 1993; Jean and Fruget, 1994; Lambolez et al., 1994; Keddy et al., 1995; Bernand et al., 1996; Dutka et al., 1996; Debus and Hund, 1997; Meier et al., 1997). "
[Show abstract][Hide abstract] ABSTRACT: Heterogeneous oily waste from an old dumping site was composted in three windrows constructed from different proportions of waste, sewage sludge, and bark. The objectives of this pilot study were to examine the usefulness of composting as a treatment method for this particular waste and to study decontamination in the composting process by using a battery of toxicity tests. Five samples from the windrow having intermediate oil concentrations were tested with toxicity tests based on microbes (Pseudomonas putida growth inhibition test, ToxiChromotest, MetPLATE, and three different modifications of a luminescent bacterial test), enzyme inhibition (reverse electron transport), plants (duckweed growth inhibition and red clover seed germination), and soil animals (Folsomia candida, Enchytraeus albidus, and Enchytraeus sp.). The luminescent bacterial tests were used as prescreening tests. Chemical analyses of samples were carried out simultaneously. Both toxicity and oil concentration, including those of polyaromatic hydrocarbons (PAHs), were reduced during composting and soil quality improved significantly. The total oil hydrocarbon concentration decreased from 90,000 to 19,000 mg/kg, measured with the IR method, in 4 months, and from 86,000 to 1400 mg/kg, measured with GC method. The concentration of PAHs decreased from 135 to 23.5 mg/kg. During the fourth month of composting (stabilization stage), the proportion of the heaviest oil fractions (asphaltenes) became dominant. Toxicity varied between different samples and between different bioassays; however, the first sample was significantly more toxic than the others, and most of the tests revealed a decrease in toxicity during the composting process.
[Show abstract][Hide abstract] ABSTRACT: The feasibility of composting of pulp and paper industry sludges was studied. The aim was to study the progress of the composting process and the toxicity and applicability of the sludges in agriculture. Five different sludges were used: two biosludges and three biosludge and primary sludge mixtures. The sludges were composted in seven piles, two smaller of them founded with leachates collection systems. The piles were monitored throughout the composting period by physical measurements, chemical analyses and toxicity tests. Also the lignin concentrations were measured from the sludges and from the soil as well as the amount of mycelium.The results showed that all sludges were easily composted and they will be suitable for the use as soil improvement in agricultural plant production. Toxicity of the sludges decreased during composting and all the sludges were proved to be non-toxic at the end of the composting. Heavy metal concentrations were low in all sludges and leachates. The leachates were also non-toxic and the concentrations of nutrients were low.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.