Search results for " Toxicity"
showing 10 items of 346 documents
Screening of physical–chemical methods for removal of organic material, nitrogen and toxicity from low strength landfill leachates
2002
Physical-chemical methods have been suggested for the treatment of low strength municipal landfill leachates. Therefore, applicability of nanofiltration and air stripping were screened in laboratory-scale for the removal of organic matter, ammonia, and toxicity from low strength leachates (NH4-N 74-220 mg/l, chemical oxygen demand (COD) 190-920 mg O2/l, EC50 = 2-17% for Raphidocelis subcapitata). Ozonation was studied as well, but with the emphasis on enhancing biodegradability of leachates. Nanofiltration (25 degrees C) removed 52-66% of COD and 27-50% of ammonia, the latter indicating that ammonia may in part have been present as ammonium salt complexes. Biological pretreatment enhanced t…
Effect of the lipid regulator Gemfibrozil in the Cladocera Daphnia magna at different temperatures.
2016
ABSTRACTIn the present study, an ecotoxicological approach to the evaluation of Gemfibrozil (GEM) as an emerging organic pollutant was done. In order to assess its toxicity, tests were conducted using the cladocera Daphnia magna. Experiments were carried out at 22°C and 28°C. EC50, feeding behavior, and chronic toxicity tests (21 days) were evaluated in D. magna exposed to GEM as well as cholesterol levels at 21-day chronic exposure. D. magna GEM EC50 values (24 h) in our experimental conditions were 148.75 and 116.24 mg L−1 at 22°C and 28°C, respectively. Test concentrations of 0.1, 0.5, 1.0, 5.0 and 7.5 mg L−1 were selected for subacute and chronic experiments. Subacute short-term test (f…
Acute Toxicity of Experimental Fertilizers Made of Spent Coffee Grounds
2017
Sustainable agriculture places new demands on agricultural practice and, in particular, plant protection treatments and fertilization. Therefore, an increase in demand for organic fertilizers of good quality is expected. In particular, the organic matter contained in the waste of the food industry or generated in households, in the absence of contamination, can be used for the production of “fertilizer”, which could be used in organic crop production. The paper presents basic characteristics of tested mixtures and the results of testing for acute toxicity of the mixture made from spent coffee grounds (SCG) modified with ash arising from the low-temperature combustion of biomass or magnesium…
Acute, chronic and sublethal effects of the herbicide propanil on Daphnia magna.
2003
Acute and chronic toxicity tests with propanil were conducted on Daphnia magna. The 24 and 48 h LC50 were 43.74 and 5.01 mg/l respectively. Chronic toxicity tests were carried out using sublethal propanil concentrations (0.07, 0.10, 0.21 and 0.55 mg/l) during 21 days. The effect of propanil on survival, reproduction and growth of D. magna organisms was monitored. The parameters used to evaluate herbicide effect on reproduction were: mean total young ones per female, mean brood size, time to first reproduction, mean number broods per female and intrinsic rate of natural increase (r). Survival and growth (body length) were also determined after 21 days of exposure to the herbicide. Reproducti…
Effect of the insecticide methylparathion on filtration and ingestion rates of Brachionus calyciflorus and Daphnia magna
1993
The freshwater rotifer Brachionus calyciflorus and the cladocera Daphnia magna were exposed to sublethal levels of methylparathion to determine the effect on filtration and ingestion rates. The experiments were performed using the unicellular algae, Nannochloris oculata in a density of 5 × 105 cell/ml. Prior to feeding experiments, preliminary acute toxicity tests were carried out to determine 24-h LC50 values for both species, these values indicated that Daphnia magna was more sensitive to methylparathion acute exposure than Brachionus calyciflorus was. Rates of filtration and ingestion declined with increasing methylparathion concentrations after an exposure of 5 h to this toxicant. The e…
Acute toxicity of experimental fertilizers made of blood meal, spent coffee ground and biomass ash
2017
Abstract The study presents the results of research on the acute toxicity of a fertilizer formulas made of spent coffee ground (SCG) with addition of ash from low-temperature combustion of biomass or ash with an admixture of magnesium sulphate and blood meal. The experimental fertilizer formulas included also rape oil used as a plasticizer for controlling the nutrients release from the fertiliser. Mustard (Sinapis alba L.), oats (Avena sativa sp. L.), cucumber (Cucumis sativus L.) and cress (Lepidium sativum L.) were used as test plants species in the experiment. The toxicity tests were performed using a standard procedure of 72 h with the use of Phytotoxkit microbiotest and fertilizer appl…
Cardiovascular effect of dental anesthesia with articaine (40 mg with epinefrine 0,5 mg % and 40 mg with epinefrine 1 mg%) versus mepivacaine (30 mg …
2011
Objectives: The aim of the present study is to compare cardiovascular safety profiles of two dental anesthetics: articaine versus two standard mepivacaine solutions used during etiological periodontal treatment in cardiovascular patients. Study Design: Using a cross-over study design, ten cardiovascular patients were randomly assigned to dental treatment with 1.8mL of a local anesthetic injected on each quadrant of the mouth: Articaine (40mg with Epinephrine 0.5mg % and 40mg with Epinephrine 1mg %) or Mepivacaine (30mg and 20mg with Epinephrine 1mg %). A computer programme enabled continuous longitudinal data collection: O2 saturation, blood pressure (BP) and heart rate (HR). Results: No se…
Novel Biocompatible Cationic Copolymers Based on Polyaspartylhydrazide Being Potent as Gene Vector on Tumor Cells
2007
Introduction. The reaction between !,"-poly(aspartylhydrazide) (PAHy), a water soluble synthetic polymer and 3-(carboxypropyl)trimethyl-ammonium chloride (CPTACl) produced copolymers bearing permanent positive charges (PAHy–CPTA) with molecular weight of 10 kDa and PAHy–CPTA copolymers differing in positive charge amount (18–58%) were chosen for biological investigations. Materials and methods. Biophysical properties of DNA/PAHy–CPTA polyplexes were evaluated in terms of DNA condensation, zeta potential and size distribution. Cytotoxicity studies on Neuro2A murine neuroblastoma cells evidenced absence of toxicity of these copolymers up to 300 2g/ml unlike linear polyethylenimine (LPEI) that…
FIBRONECTIN (FN) AND UROTHELIAL DAMAGE SECONDARY TO ADJUVANT INTRAVESICAL THERAPY
2014
Introduction and Objectives: Intravesical chemotherapy has been proven effective in preventing recurrence of low-risk non-muscle invasive bladder cancer (NMIBC). BCG is recognised as the best conservative treatment for intermediate and high risk NMIBC. Maintenance for at least one year is required to ameliorate the efficacy of adjuvant therapy. Discomfort and toxicity often cause interruption of adjuvant therapy, BCG particularly. Almost 50% of the patients undergoing BCG does not complete one year. A biomarker of urothelium damage would be helpful for timely detection of toxicity in order to ameliorate patient’s tolerance and compliance. The aim of the present study was to evaluate the gen…
Do laboratory exposures represent field exposures? Effects of sediments contaminated by wood industry on yolk-sac fry of rainbow trout (Oncorhynchus …
2015
Purpose. Risk assessment of contaminated sediments is routinely based on laboratory exposures. The purpose of this work was to study if sediments contaminated by the chemical wood industry cause developmental defects in fish fry and how well a laboratory exposure correlates with a field exposure. Materials and methods. Newly hatched yolk-sac fry of rainbow trout (Oncorhynchus mykiss) were exposed in the laboratory and in situ. In the laboratory, the fish were placed in contact with either clean or contaminated sediment in aquaria. In the field, half of the fish were placed in contact with the lake sediment and the other half were similarly caged 2 m above it, to discern the effects of the s…