scholarly journals Toxicity of leachates from pilot reactors simulating a landfill with different concentrations of AgNP

2019 ◽  
Vol 24 (6) ◽  
pp. 1089-1094
Author(s):  
Raphael Zanelato ◽  
Isabela da Cruz Bonatto ◽  
José Julio Barrios Restrepo ◽  
Rodrigo Costa Puerari ◽  
William Gerson Matias ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Acute Toxicity ◽  
Aquatic Ecosystems ◽  
Aquatic Invertebrates ◽  
Trophic Levels ◽  
Toxicity Tests ◽  
Treatment Efficiency ◽  
Landfill Leachates ◽  
Acute Toxicity Tests

ABSTRACT This work’s objective was to verify the leachates toxicity from pilot reactors (PR) simulating a landfill containing different concentrations of silver nanoparticles (AgNP). Acute toxicity tests (48 h) with Daphnia magna were carried out in leachates containing 50, 150 and 450 mg AgNP.kg-1, in addition to a blank for control. Toxicity tests with the pure solution of silver nanoparticle and leachates resulted by the reactors were performed. The acute toxicity tests performed with D. magna confirmed the toxicity of the leachates, as well as confirmed that the silver nanoparticles are toxic, presenting EC50 (48 h) of 0.63 µg.L-1 of pure nanoparticle and ranging from 1.52 to 3.37% for the leachates. Overall, the results from the present study indicate that exposures of aquatic invertebrates to silver nanoparticles could have important ecological effects on lower trophic levels in aquatic ecosystems. The results may contribute to a better understanding of the quality of municipal solid waste (MSW) landfill leachates, with reference to nanoparticle interference and consequent treatment efficiency.

Acute toxicity tests using earthworms to estimate ecological quality of compost and digestate

2017 ◽  
Vol 20 (1) ◽  
pp. 552-560 ◽  
Author(s):  
Alberto Pivato ◽  
Maria Cristina Lavagnolo ◽  
Barbara Manachini ◽  
Roberto Raga ◽  
Giovanni Beggio ◽  
...  
Keyword(s):  
Acute Toxicity ◽  
Toxicity Tests ◽  
Ecological Quality ◽  
Acute Toxicity Tests

Acute Toxicity Testing with Juvenile White Sturgeon (Acipenser transmontanus)

1998 ◽  
Vol 33 (1) ◽  
pp. 95-110 ◽  
Author(s):  
W.R. Bennett ◽  
A.P. Farrell
Keyword(s):  
Acute Toxicity ◽  
Swimming Performance ◽  
Juvenile Fish ◽  
Toxicity Testing ◽  
White Sturgeon ◽  
Acipenser Transmontanus ◽  
Toxicity Tests ◽  
Fraser River ◽  
Acute Toxicity Tests ◽  
Acute Toxicity Testing

Abstract The primary goal of this study was to investigate the possibility of using early life stages of white sturgeon (Acipenser transmontanus) (eggs, larvae and fry) as a species relevant to the Fraser River, B.C., for the acute and sublethal toxico-logical testing of forest industry effluents. Here we report the first successful acute toxicity tests for 8-day-old larvae and 42-day-old fry exposed to several chemicals known to be released into the Fraser River (i.e., 6 monochlorovanillin [6 MVAN], 4,5 dichloroguaiacol [4,5 DCG], 4,5 dichlorocatechol [4,5 DCAT], pentachlorophenol [PCP], and didecyldimethylammonium chloride [DDAC]). In most cases, white sturgeon fry were at the lower end of the range for acute toxicity values for chlorinated phenolic compounds, when compared with other juvenile fish species, and they were extremely sensitive to DDAC. The larval stage was usually more sensitive than the fry stage. Acute toxicity tests with fertilized eggs were unsuccessful. A postexposure growth study was inconclusive because neither control nor toxicant-exposed larvae and fry withstood the additional handling used for measuring body mass. At 62-days-old, fry were more tolerant of handling. This allowed measurement of their swimming performance. Although we have concerns about the reliability of using larvae for acute toxicity testing at this time, 60-day-old white sturgeon fry would appear to be both a sensitive and relevant species for assessing environmental impacts relevant to the Fraser River.

Post-treatment of sanitary landfill leachate by coagulation–flocculation using chitosan as primary coagulant

2016 ◽  
Vol 74 (1) ◽  
pp. 246-255 ◽  
Author(s):  
Inara Oliveira do Carmo Nascimento ◽  
Ana Rosa Pinto Guedes ◽  
Louisa Wessels Perelo ◽  
Luciano Matos Queiroz
Keyword(s):  
Acute Toxicity ◽  
Removal Efficiency ◽  
Landfill Leachate ◽  
Post Treatment ◽  
Toxicity Tests ◽  
Process Conditions ◽  
Sanitary Landfill ◽  
Average Growth ◽  
Acute Toxicity Tests ◽  
Sanitary Landfill Leachate

Chitosan was chosen as an alternative primary coagulant in a complementary coagulation–flocculation treatment of sanitary landfill leachate with the aim of removing recalcitrant organic matter. In order to optimize the process conditions, central composite design and response surface methodology were applied. To evaluate the performance of the process using chitosan, we also carried out tests with aluminium sulphate (Al2 (SO4)3.14 H2O) as coagulant. In addition, acute toxicity tests were carried using the duckweed Lemna minor and the guppy fish Poecilia reticulata as test organisms. The analytic hierarchy process was employed for selecting the most appropriate coagulant. Mean values of true colour removal efficiency of 80% and turbidity removal efficiency of 91.4% were reached at chitosan dosages of 960 mg L−1 at pH 8.5. The acute toxicity tests showed that organisms were sensitive to all samples, mainly after coagulation–flocculation using chitosan. CE50 for L. minor was not determined because there was no inhibition of the average growth rate and biomass production; LC50 for P. reticulata was 23% (v v−1). Multi-criteria analysis showed that alum was the most appropriate coagulant. Therefore, chitosan as primary coagulant was not considered to be a viable alternative in the post-treatment of landfill leachate.

scholarly journals Toxicity of Methanol to Fish, Crustacean, Oligochaete Worm, and Aquatic Ecosystem

2004 ◽  
Vol 23 (1) ◽  
pp. 55-63 ◽  
Author(s):  
A. Kaviraj ◽  
F. Bhunia ◽  
N. C. Saha
Keyword(s):  
Aquatic Ecosystem ◽  
Aquatic Invertebrates ◽  
Feeding Rate ◽  
Toxicity Tests ◽  
Freshwater Teleost ◽  
Branchiura Sowerbyi ◽  
Acute Toxicity Tests ◽  
Gill Lamellae ◽  
Sublethal Concentrations ◽  
Growth And Reproduction

Static renewal bioassays were conducted in the laboratory and in outdoor artificial enclosures to evaluate toxic effects of methanol to one teleost fish and two aquatic invertebrates and to limnological variables of aquatic ecosystem. Ninety-six-hour acute toxicity tests revealed cladoceran crustacea Moina micrura as the most sensitive to methanol (LC50, 4.82 g/L), followed by freshwater teleost Oreochromis mossambicus (LC50, 15.32 g/L) and oligochaete worm Branchiura sowerbyi (LC50, 54.89 g/L). The fish, when exposed to lethal concentrations of methanol, showed difficulties in respiration and swimming. The oligochaete body wrinkled and fragmented under lethal exposure of methanol. Effects of five sublethal concentrations of methanol (0, 23.75, 47.49, 736.10, and 1527.60 mg/L) on the feeding rate of the fish and on its growth and reproduction were evaluated by separate bioassays. Ninety-six-hour bioassays in the laboratory showed significant reduction in the appetite of fish when exposed to 736.10 mg/L or higher concentrations of methanol. Chronic toxicity bioassays (90 days) in outdoor enclosures showed a reduction in growth, maturity index and fecundity of fish at 47.49 mg/L or higher concentrations of methanol. Primary productivity, phytoplankton population, and alkalinity of water were also reduced at these concentrations. Chronic exposure to 1527.60 mg/L methanol resulted in damages of the epithelium of primary and secondary gill lamellae of the fish. The results revealed 23.75 mg/L as the no-observed-effect concentration (NOEC) of methanol to freshwater aquatic ecosystem.

scholarly journals Nano-sized zeolites as modulators of thiacloprid toxicity onChironomus riparius

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3525 ◽  
Author(s):  
Carla S. Lorenz ◽  
Anna-Jorina Wicht ◽  
Leyla Guluzada ◽  
Barbara Crone ◽  
Uwe Karst ◽  
...  
Keyword(s):  
Acute Toxicity ◽  
Imaging Techniques ◽  
Toxicity Tests ◽  
Biting Midge ◽  
Ms Imaging ◽  
Icp Ms ◽  
Small Primary ◽  
Acute Toxicity Tests ◽  
Investigation Period ◽  
Adsorption Rates

This study investigated whether zeolites of different size (Y30 (nano-sized) and H-Beta(OH)-III (forming large aggregates/agglomerates composed of 50 nm small primary particles)) exerted acute toxicity on larvae of the non-biting midge,Chironomus riparius, and whether such zeolites are able to modulate the toxicity of a common insecticide, thiacloprid, by means of adsorption of a dissolved toxicant. We conducted acute toxicity tests with fourth instar larvae ofC. riparius. In these tests, larvae were exposed to zeolites or thiacloprid solely, or to mixtures of both compounds. The mixtures comprised 1.0 µg/L thiacloprid in addition to low (5.2 mg/L), medium (18.2 mg/L), and high (391.7 mg/L) zeolite concentrations, resulting in different adsorption rates of thiacloprid. As biological endpoints, changes in mortality rates and in behavior were monitored every 24 h over a total investigation period of 96 h. Furthermore, we conducted chemical analyses of thiacloprid in the medium and the larvae and located the zeolite particles within the larvae by LA-ICP-MS imaging techniques. Our results demonstrate that both types of zeolites did not exert acute toxicity when applied as single-substances, but led to reduced acute toxicity of thiacloprid when applied together with thiacloprid. These results are in line with the sorption properties of zeolites indicating reduced bioavailability of thiacloprid, although our data indicate that thiacloprid can desorb from zeolites to some extent. While freely dissolved (i.e., non-sorbed) fraction of thiacloprid was a good parameter to roughly estimate toxic effects, it did not correlate with measured internal thiacloprid concentrations. Moreover, it was shown that both zeolite types were ingested by the larvae, but no indication for cellular uptake of them was found.

Acute Toxicity of Copper, Cadmium, and zinc to Larvae of the Crab Paragrapus quadridentatus (H. Milne Edwards), and Implications for Water Quality Criteria

1978 ◽  
Vol 29 (1) ◽  
pp. 1 ◽  
Author(s):  
M Ahsanullah ◽  
GH Arnott
Keyword(s):  
Water Quality ◽  
Heavy Metal ◽  
Acute Toxicity ◽  
Metal Toxicity ◽  
Quality Criteria ◽  
Toxicity Tests ◽  
Water Quality Criteria ◽  
Minimal Risk ◽  
Larval Stages ◽  
Acute Toxicity Tests

Acute toxicity tests were carried out on the larvae of P. quadridentatus and 96-h LC50 values of 0.17, 0.49, and 1.23 mg/l were determined for copper, cadmium, and zinc respectively. Potency ratios of the three metals were as follows: Cu/Cd 3.1, Cu/Zn 7.2, and Cd/Zn 2.4. Larvae were found to be nine times more sensitive to zinc and at least 29 times more sensitive to cadmium than were adults. The larval 96-h LC50 values multiplied by an application factor of 0.01 (as recommended in Victorian water quality criteria) results in derived 'safe' concentrations, which in the case of copper and zinc are below the stated 'minimal risk concentrations' of 10 and 20 �g/I respectively. In view of the known greater sensitivity of larvae of many taxa to heavy metal toxicity, the validity of using the same application factor for both adult and larval stages is questioned.

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