Water and sediment ecotoxicity studies in Temuco and Rapel River Basin, Chile
ABSTRACT Five samples were collected from the Rapel River Basin near the city of Rancagua and three from the city of Temuco. Three of the samples were collected from raw drinking water supplies. The following bioassays were performed on some or all of the samples: Microtox; Microtox solid phase test; SOS-Chromotest with and without S9; Toxi-Chromotest; Sediment-Chromotest; Panagrellus redivivus percent survival and percent maturation; submitochondrial reverse electron transfer and forward electron transfer tests; Daphnia magna 24 h acute toxicity; ECHA biocide monitor, and the competitive immunoassay tests for benomyl, metolachlor, atrazine, and triazines. All the sampling sites were positive for the presence of genotoxicants requiring S9 activation while three sites also indicated the presence of direct-acting genotoxicants/mutagens (−S9). Also, all the sites were positive for the presence of pesticides. In some samples there was 100% inhibition of P. redivivus maturation. Details and discussion on the implication of the results are presented. © 1996 by John Wiley & Sons, Inc.
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ABSTRACT: Traditionally, chemical analyses are used in the assessment of contaminated soil and in monitoring the efficiency of soil remediation processes. We investigated if chemical analysis could be supported and even partly replaced by biological toxicity tests. In two case studies creosote-contaminated soil was composted outdoors in 5- and 100-m3 windrows. Degradation of polyaromatic hydrocarbons (PAHs) was followed by chemical analysis and toxicity tests. Polyaromatic hydrocarbons were quantified and identified by HPLC. Because the soil was also contaminated by copper-, chromium-, and arsenic-containing fungicides, these elements were analyzed by atomic absorption spectrometry. The toxicity of soil samples was assessed by a soil-contact modification of the luminescent bacteria (Vibrio fischeri) test and in the other case also by enzyme synthesis inhibition (Toxi-ChromoPad test, Escherichia coli). The toxicity of soil water extracts was measured by the standard luminescent bacteria (V. fischeri) test and bacterial (Pseudomonas putida) growth inhibition test. After the first 4 months of the composting period the total amount of PAHs was reduced in all windrows, and in particular, the loss of two- and some three-ring compounds was high, almost 90%. Toxicity decreased concurrently with the decrease in PAH concentration during composting, but after 4 months, one of the piles inoculated with mycobacteria and containing more three- and four-ring compounds was found to be more toxic than at the beginning. After the next summer, total PAH content was further reduced but some four-ring or heavier compounds were demonstrated to be poorly degraded. The toxicity was also reduced to the same level as in the control pile. The total PAH content and the toxicity were both reduced significantly during 5 months of composting.Ecotoxicology and Environmental Safety 11/2002; 53(2):323-9. · 2.20 Impact Factor
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ABSTRACT: Sediments are the sink for particle-sorbed contaminants in aquatic systems and can serve as a reservoir of toxic contaminants that continually threaten the health and viability of aquatic biota. This work is a comprehensive review of published studies that investigated the genotoxicity of sediments in rivers, lakes and marine habitats. The Salmonella mutagenicity test is the most frequently used assay and accounts for 41.1% of the available data. The Salmonella data revealed mutagenic potency values for sediment extracts (in revertants per gram dry weight) that spans over seven orders of magnitude from not detectable to highly potent (10(5) rev/g). Analyses of the Salmonella data (n=510) showed significant differences between rural, urban/industrial, and heavily contaminated (e.g., dump) sites assessed using TA98 and TA100 with S9 activation. Additional analyses showed a significant positive correlation between Salmonella mutagenic potency (TA98 and TA100 with S9) and PAH contamination (r2=0.19-0.68). The second and third most commonly used assays for the analysis of sediments and sediment extracts are the SOS Chromotest (9.2%) and the Mutatox assays (7.8%), respectively. These assays are frequently used for rapid initial screening of collected samples. A variety of other in vitro endpoints employing cultured fish and mammalian cells have been used to investigate sediment genotoxic activity. Endpoints investigated include sister chromatid exchange frequency, micronucleus frequency, chromosome aberration frequency, gene mutation at tk and hprt loci, unscheduled DNA synthesis, DNA adduct frequency, and DNA strand break frequency. More complex in vivo assays have documented a wide range of effects including neoplasms and preneoplastic lesions in fish and invertebrate exposed ex situ. Although costly and time consuming, these assays have provided definitive evidence linking sediment contamination and a variety of genotoxic and carcinogenic effects observed in situ.Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis 12/2004; 567(2-3):151-225. · 3.90 Impact Factor
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ABSTRACT: Two different forest industry wastewater sludges were composted in piles. The piles were founded with leachate collection systems. The aim was to study the progress of the composting process, the amount and quality of leachates as well as the toxicity of the sludges and leachates. The sludges consisted of mixtures of primary and biosludge. The piles were monitored for eight months by physical measurements, chemical analyses and toxicity tests. The leachates were collected for six months. The lignin concentrations and the amount of mycelium were measured from the sludges and from the soil. Test plots and control plots were established to a field with different amounts of composted sludge in order to study the applicability of the sludges in agriculture. The results showed that both sludges were amenable to composting. The original sludges were toxic but the toxicity decreased during composting and all the sludges were proved to be non- toxic at the end of composting. The leachates were determined non-toxic and the heavy metal concentrations were low in both sludges and leachates. The sludges proved to be suitable for use as soil improver in agricultural plant production. Keywords Agricultural use; composting; pulp and paper industry; toxicity; wastewater sludges01/2000;