scholarly journals A Comparison of Acute Toxicity of Biodiesel, Biodiesel Blends and Diesel on Aquatic Organisms

2021 ◽  
Author(s):  
Nalissa Farrah Khan

The increasing demand of alternative energy sources has created interest in biodiesel and biodiesel blends; biodiesel is promoted as a diesel substitute. Like diesel spills, biodiesel spills can have deleterious effects on aquatic environments. The effect of neat biodiesel, biodiesel blends and diesel on O. mykiss and D. magna was evaluated using acute toxicity testing. Static non-renewable bioassays of freshwater organisms containing B100, B50, B20, B5 and conventional diesel fuel were used to compare the acute effects of biodiesel to diesel. Mortality was the significant endpoint measurement in this study; percent mortality and lethal concentration (LC50) at different exposure times were determined from the acute toxicity tests performed. Trials were considered valid if the controls exhibited more than 90% survival. Based on percent mortality and LC50 values, a toxicity ranking of fuels was developed. The results of the definitive tests indicated that diesel is more toxic than neat biodiesel or biodiesel blends. This approach can provide insights into the lethality of biodiesel spills in the aquatic environment.

2021 ◽  
Author(s):  
Nalissa Farrah Khan

The increasing demand of alternative energy sources has created interest in biodiesel and biodiesel blends; biodiesel is promoted as a diesel substitute. Like diesel spills, biodiesel spills can have deleterious effects on aquatic environments. The effect of neat biodiesel, biodiesel blends and diesel on O. mykiss and D. magna was evaluated using acute toxicity testing. Static non-renewable bioassays of freshwater organisms containing B100, B50, B20, B5 and conventional diesel fuel were used to compare the acute effects of biodiesel to diesel. Mortality was the significant endpoint measurement in this study; percent mortality and lethal concentration (LC50) at different exposure times were determined from the acute toxicity tests performed. Trials were considered valid if the controls exhibited more than 90% survival. Based on percent mortality and LC50 values, a toxicity ranking of fuels was developed. The results of the definitive tests indicated that diesel is more toxic than neat biodiesel or biodiesel blends. This approach can provide insights into the lethality of biodiesel spills in the aquatic environment.


1998 ◽  
Vol 33 (1) ◽  
pp. 95-110 ◽  
Author(s):  
W.R. Bennett ◽  
A.P. Farrell

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.


2020 ◽  
Vol 36 (7) ◽  
pp. 467-476
Author(s):  
Halis Boran

Metal-based nanoparticles (NPs) can release metal ions that are toxic to aquatic organisms; however, whether the toxicity is from metal ions rather than unique “nano-scale” effects of the NPs is unresolved. The present study aimed to compare the toxicity of Cu2+ and Cu-NPs in larval zebrafish ( Danio rerio) to clarify whether toxic effects are attributable to release of Cu ions and to determine the effect of the chelating agent ethylenediaminetetraacetic acid (EDTA) and calcium hardness (as CaCO3) on the Cu toxicity. First, the acute toxicity (96-h lethality) of Cu-NPs was determined in comparison to aqueous Cu in larvae exposed to CuSO4, and subsequently, sublethal tests with Cu-NPs and CuSO4 were conducted with additions of EDTA or calcium ions to evaluate alterations in expression of metallothionein-2 ( MT2) gene transcripts (quantitative real-time polymerase chain reaction). Acute toxicity of Cu in larvae exposed to CuSO4 was greater (LC50 = 226 µg Cu/L) than for larvae exposed to Cu-NPs (LC50 = 648 µg Cu/L). The expression of MT2 increased with Cu concentration ( p < 0.05), and the slope of the linear regression was significantly greater in fish exposed to CuSO4 (slope = 0.090) compared to Cu-NPs (slope = 0.011). Cu2+ was 2.9-fold more toxic than Cu-NPs. The presence of 5 mg/L EDTA and 220 mg/L CaCO3 significantly reduced the expression of MT2 (1.8-fold for EDTA, 2.3-fold for CaCO3) in larvae exposed to CuSO4. For larvae exposed to Cu-NPs, the presence of EDTA reduced the expression of MT2 (1.7-fold) relative to Cu-NP concentration. While Cu-NPs induced MT2 expression, the differences in concentration relationships of MT2 expression between Cu-NPs and CuSO4 indicated that factors other than release of Cu ions from Cu-NPs influenced acute toxicity of Cu-NPs. The conclusion drawn from this ecotoxicological risk assessment was that EDTA and calcium significantly decreased Cu toxicity in freshwater fish.


Author(s):  
Eva Poštulková ◽  
Radovan Kopp

The emergence and development of new algicidal products is caused by the ever increasing popularity of garden ponds as well as the use of these products in the fisheries sector, especially for disposal of cyanobacteria and algae. Most frequent means of combating cyanobacteria and algae are applications of algicidal substances. Newly developed algaecides include Guanicid and polyhexamethylene guanidine hydrochloride (PHMG). The aim of the study was to identify toxic effects of Guanicid and PHMG on zebrafish (Danio rerio) and green algae (Desmodesmus communis). We determined the acute toxicity in fish according to ČSN EN ISO 7346-1, and conducted the freshwater algae growth inhibition test according to ČSN ISO 8692 methodology. For inhibition tests with green algae we chose Guanicid and PHMG concentrations of 0.001, 0.005, and 0.010 ml/L. For fish short-term acute toxicity tests we chose Guanicid concentrations of 0.010, 0.050, 0.150, 0.200, 0.250, and 0.300 ml/L and PHMG concentrations of 0.010, 0.025, 0.050, 0.075, 0.100, and 0.125 ml/L. In case of zebrafish (Danio rerio), the LC50 value for Guanicid is 0.086 ml/L, while the LC50 value for PHMG is 0.043 ml/L. Effects of Guanicid on inhibition of green algae (Desmodesmus communis) appear highly significant (p < 0.010) at a concentration of 0.010 ml/L. For PHMG, these effects are highly significant (p < 0.001) at concentrations of 0.005 and 0.010 ml/L in 48 hours.


The Analyst ◽  
2014 ◽  
Vol 139 (18) ◽  
pp. 4696-4701 ◽  
Author(s):  
Insup Jung ◽  
Ho Bin Seo ◽  
Ji-eun Lee ◽  
Byoung Chan Kim ◽  
Man Bock Gu

The use of genetically engineered bioluminescent bacteria, in which bioluminescence is induced by different modes of toxic action, represents an alternative to acute toxicity tests using living aquatic organisms (plants, vertebrates, or invertebrates) in an aqueous environment.


1996 ◽  
Vol 34 (7-8) ◽  
pp. 109-116 ◽  
Author(s):  
Henk Heida ◽  
Ron van der Oost

The toxicity of the pore water from the sediments of nine fresh water systems in and around Amsterdam City was studied with the aid of four acute toxicity tests. Based on preliminary chemical analysis, the sediments of three of the tested systems had to be considered strongly contaminated, according to the quality standards derived from the Dutch Law on Soil Pollution Control. In addition, the acute toxicity of groundwater from a heavily contaminated industrial building site was also examined. The following toxicity tests were used. 1. Microtox bioluminescence assay, or Microtox test. This test is based on the inhibition of bioluminescence of Photobacterium phosphoreum; 2. Rotoxkit F, based on the LC50 of Brachionus calyciflorus; 3. Thamnotoxkit F, based on the LC50 of Thamnocephalus plaxyurus; 4. Toxichromotest, based on the inhibition of β-galactosidase formation in Escherichia coli. The objective of the study was to test the feasibility of the toxicity tests as a tool for the risk evaluation of contaminated sites, both in water and on land. The results indicated that the sediments of three of the eight sites studied could be classified as toxic and one site even as very toxic. The outcome of the toxicity testing confirmed the results of the chemical analysis for only one site. It appeared that the Microtox and the Thamnotoxkit F tests were the most sensitive acute toxicity tests. It could be concluded that the resolution of the toxicity tests scrutinized was insufficient to reliably discriminate the environmental quality of the sediments at the locations studied. The bioassays, however, are useful in determining remediation priorities of contaminated sites.


2001 ◽  
Vol 2001 (2) ◽  
pp. 935-940 ◽  
Author(s):  
William R. Gala ◽  
Gary A. Rausina ◽  
Michael J. Ammann ◽  
Paul Krause

ABSTRACT Aquatic toxicity information is critical to provide scientifically defensible estimates of ecological impact and natural resource injury to aquatic organisms resulting from a petroleum spill. For most crude oils, the availability of aquatic toxicity information is a significant data gap. As part of Chevron's oil-specific properties summary sheet project, a series of marine fish (silversides, top smelt) and invertebrate (mysid shrimp) acute toxicity tests on five crude oils with extensive chemical analysis (e.g., VPH C6–C9, CROSERF VOCs, EPH C10–C32, PAHs) of exposure concentrations have been performed. Acute toxicity studies were conducted under standard test guidelines. ASTM D 6081 procedures were used to prepare individual water extracts, also called water-accommodated fractions (WAFs), of each test concentration to which the test organisms were exposed. WAF preparation and testing was done in tightly closed containers with minimal headspace to reduce volatilization and maintain stable exposure levels of dissolved hydrocarbons as much as possible. Also, WAFs were replenished daily with fresh test solution. Since toxicity results are expressed as the mean exposure concentration of a particular subset of the petroleum compounds in the WAF that resulted in 50% lethality in the test species, the LC50 values in μg/L will vary depending on which subset is used to describe the effect of the oil on the aquatic organisms. Additionally, since the aquatic organisms are exposed to a mixture of hydrocarbons in the WAF, LC50 values expressed as one subset's concentration are not independent of the presence of other petroleum constituent types. The results indicate that generally invertebrates (i.e., mysid) are more sensitive than fish. LC50s expressed as total polycyclic hydrocarbons (PAHs) showed the least variability—96-hour LC50s for total PAHs ranged from 19–36 μg/L and 30–128 μg/L for mysid and fish, respectively.


2014 ◽  
Vol 26 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Raquel Aparecida Moreira ◽  
Adrislaine da Silva Mansano ◽  
Lidiane Cristina da Silva ◽  
Odete Rocha

AIM: In this study we compared the sensitivity of three species of Cladocera, Daphnia magna, Ceriodaphnia silvestrii and Macrothrix flabelligera, to the commercial product of the herbicide Atrazine, the Atrazine Atanor 50 SC® (500 g/L), widely used on crops in Brazil. METHODS: Acute toxicity tests were performed at the nominal atrazine concentrations 2.25, 4.5, 9.0, 18.0, 36 and 72 mg L-1, on C. silvestrii and M. flabelligera and at 2.25, 4.5, 9.0, 18.0, 36, 72 and 144 mg L-1 on D. magna. The range of concentrations tested was established in a series of preliminary tests. RESULTS: The toxicity tests showed that the two species naturally occurring in water bodies in Brazil were more susceptible than Daphnia magna. The effective concentrations of Atrazine Atanor 50 SC® (EC50- 48 h) to the species M. flabelligera, C. silvestrii and D. magna were 12.37 ± 2.67 mg L-1, 14.30 ± 1.55 mg L-1 and 50.41 ± 2.64 mg L-1, respectively. Furthermore, when EC50 observed here for M. flabelligera and C. silvestrii were compared with published values of EC50 or LC50 (mg L-1) for various aquatic organisms exposed to atrazine, it was seen that these two cladocerans were the most sensitive to the herbicide. CONCLUSIONS: Considering these results and the broad distribution of C. silvestrii and M. flabelligera in tropical and subtropical regions, it is concluded that these native species would be valuable test organisms in ecotoxicological tests, for the monitoring of toxic substances in tropical freshwaters.


2013 ◽  
Vol 334-335 ◽  
pp. 77-82 ◽  
Author(s):  
Ch’ng Shiau Ying ◽  
A. Andriyana ◽  
Erwan Verron ◽  
Roslina Ahmad

Petroleum-based fuel is facing significant depletion issue due to its limited reserves and increasing demand from various industries. Thus, various considerations from economical, environmental and political concerns have motivated researchers to develop alternative energy sources such as biofuel to decrease dependence on petroleum-based fuel. However, the changes in the fuel composition of biofuel affect the material compatibility. In engineering applications where elastomeric components are exposed to hostile environment such as palm biodiesel medium, at least two aspects contribute to the degradation of the materials during the service: diffusion of the liquids leading to swelling and fluctuating multiaxial mechanical loading leading to fatigue failure. Therefore, it is of utmost importance to study the mechanical responses of elastomers under this coupled diffusion-mechanical loading in order to predict accurately their fatigue failure. The present work investigates the swelling of elastomers under simultaneous diffusion of palm biodiesel and multiaxial large deformations.


1994 ◽  
Vol 29 (1) ◽  
pp. 89-102 ◽  
Author(s):  
W.R. Ernst ◽  
P. Hennigar ◽  
K. Doe ◽  
S. Wade ◽  
G. Julien

Abstract Samples of leachate were obtained at four locations in effluent streams from a municipal waste landfill near Halifax, Nova Scotia. Samples were analyzed for a number of physical and chemical parameters using standard laboratory procedures. Samples were also screened to identify organic chemicals by matching mass spectrometer output against a reference spectrum library. Static acute toxicity tests (48 h to 96 h) were also conducted on samples using rainbow trout (Oncorhynchus mykiss), brook trout (Salvelinus fontinalis) and water fleas (Daphnia magna) as test organisms. The acute toxicity of leachate was primarily due to its ammonia content; however, the chronic effects on aquatic organisms of the range of organic chemicals identified in these samples remains undetermined. Paradoxically, the leachate discharge to the receiving water body reduced the toxic potential of that water to the organisms tested.


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