scholarly journals TOXICITY OF PHYSICALLY AND CHEMICALLY DISPERSED OILS UNDER CONTINUOUS AND ENVIRONMENTALLY REALISTIC EXPOSURE CONDITIONS: APPLICABILITY TO DISPERSANT USE DECISIONS IN SPILL RESPONSE PLANNING

2001 ◽  
Vol 2001 (2) ◽  
pp. 1249-1255 ◽  
Author(s):  
James R. Clark ◽  
Gail E. Bragin ◽  
Eric J. Febbo ◽  
Daniel J. Letinski
Keyword(s):  
Standardized Testing ◽  
Fuel Oil ◽  
Environmental Research ◽  
Continuous Exposure ◽  
Exposure Test ◽  
Test Species ◽  
Response Planning ◽  
Dispersed Oil ◽  
Testing Protocols ◽  
Exposure Conditions

ABSTRACT As part of efforts to develop standardized testing protocols under the Chemical Response to Oil Spills Environmental Research Forum (CROSERF) and apply the results to real-world scenarios, three types of oils and two dispersants were tested in both continuous and short-term spiked exposures using the early life-stages of several marine organisms. Test species included embryo-larval stages of Pacific oyster (Crassostrea gigas), two marine mysids (Holmesimysis costata and Mysidopsis bahia), and two marine fishes (turbot, Scophthalmus maximus and inland silverside, Menidia beryllina). Oils were physically dispersed in seawater by vortex mixing in a flask and chemically dispersed using the same approach with COREXIT® 9527 or COREXIT® 9500 applied in a 10:1 oil-to-dispersant ratio to generate maximum exposure concentrations. Continuous exposure tests followed standard testing protocols for 96-hour or 48-hour duration, according to demands of the test species. Spiked exposures reflect continuous dilution of water column concentrations (half-life ∼107 minutes), as observed in the field when oil is dispersed into open waters. Results are reported as the acute LC50s. Tests oils included fresh and weathered Kuwait crude, fresh Forties crude, and a Medium Fuel Oil (MFO) mix. Exposure concentrations for oil tests were quantified using gas chromatography and expressed as the sum of the C10 to C36 components, or TPH(resoived). Dispersant exposure concentrations were verified by UV spectrophotometric analysis. Not all species were tested with each oil and dispersant. For dispersants tested individually, constant exposure LC50s ranged from 3 to 75 mg/L, with oyster the most sensitive and turbot the least sensitive species. Spiked exposure LC50s ranged from 14 to >1055 mg/L among all test species. Dispersants were up to 36 times less toxic under spiked exposure conditions compared to similar treatments under constant exposure conditions. For oils, LC50s based on TPH(resolved) are similar for both the physically and chemically dispersed oil, demonstrating that dispersant did not increase the toxicity of oils based on measured exposures. Under constant exposure conditions, test species are very similar in sensitivity to the oils, with most LC50s around 0.5 ppm TPH(resolyed). Spiked exposures were 4 to 100 fold less toxic to these test organisms. The more environmentally realistic spiked exposures demonstrate that standard, continuous exposure test data overestimate the potential toxicity of dispersed oil. When laboratory toxicity data are used as part of a dispersant approval process for spill response, the decision should take into account whether exposure durations and sensitivity of test species are representative of conditions in the spill area.

COOPERATIVE STUDIES ON THE TOXICITY OF DISPERSANTS AND DISPERSED OIL TO MARINE ORGANISMS: A 3-YEAR FLORIDA STUDY

2001 ◽  
Vol 2001 (2) ◽  
pp. 1237-1241 ◽  
Author(s):  
Dana L. Wetzel ◽  
Edward S. Van Fleet
Keyword(s):  
Crude Oil ◽  
Standard Test ◽  
Sciaenops Ocellatus ◽  
Crude Oils ◽  
Continuous Exposure ◽  
Test Species ◽  
Dispersed Oil ◽  
Test Organisms ◽  
Flow Through ◽  
Exposure Conditions

ABSTRACT The present study was conducted to assess the toxicity of the water-accommodated fraction (WAF) and the chemically enhanced WAF (CE-WAF) of selected crude oils for both weathered and fresh oil. Test organisms included two standard test species, Mysidopsis bahia and Menidia beryllina, and a commercially important Florida marine fish, Sciaenops ocellatus. Tests ascertaining LC50 values were conducted under continuous exposure and spiked (declining exposure using flow-through toxicity chambers) conditions using Venezuelan Crude Oil (VCO), Prudhoe Bay Crude Oil (PBCO), and COREXIT® 9500 dispersant on the above species. Data suggest that the dispersant is less toxic than the WAF and CE-WAF of the tested crude oils. The toxicity of the CE-WAF of fresh VCO is similar to that of other oils under continuous exposure conditions, but may be slightly more toxic to some species under spiked exposure conditions. The CE-WAF of fresh VCO appears to be less toxic than the corresponding WAF for M. bahia, M. beryllina, and S. ocellatus. Fresh VCO appears to be much more toxic to M. bahia and M. beryllina than weathered VCO in spiked exposure tests for both the WAF and CE-WAF. The WAF of PBCO is apparently less toxic to the test organisms than the corresponding WAF of fresh VCO. The LC50 values of M. bahia with CE-WAF fractions of both fresh VCO and PBCO are similar, while the same PBCO CE-WAF fraction is less toxic for M. beryllina than fresh VCO CE-WAF. The toxicity of oils and dispersants were lowest in the spiked exposure weathered oil tests, which may be most representative of an oil spill under natural environmental conditions.

Changes in Aggressive Interaction in Adjacently Territorial Convict Cichlids (Cichlasoma Nigrofasciatum): a Study of Habituation

Behaviour ◽  
1971 ◽  
Vol 40 (1-2) ◽  
pp. 43-54 ◽  
Author(s):  
Michael J. Herz ◽  
Harman V.S. Peeke ◽  
James E. Gallagher
Keyword(s):  
Ecological Niche ◽  
Prolonged Exposure ◽  
Continuous Exposure ◽  
Aggressive Interaction ◽  
Minute Exposure ◽  
Cichlasoma Nigrofasciatum ◽  
Uniform Pattern ◽  
Convict Cichlids ◽  
Stimulus Source ◽  
Exposure Conditions

AbstractPairs of male Convict Cichlids (Cichlasoma nigrofasciatum) were isolated from each other and then exposed in adjoining territories under one of two exposure conditions, either daily 20 minute exposure for 38-44 days or a massed continuous exposure for 24 or 28 hours. The incidence of biting and the duration of chin display for each fish was recorded. The duration of the chin display described a near uniform pattern of attenuation for both exposure conditions. The waning of the biting response was evident but it was more variable than the chin display. It was concluded that these behaviors both tend to habituate with repeated or constant exposure to the same stimulus source and that prolonged exposure facilitates the habituation of aggressiveness between territorial neighbors, thus promoting peace in a particular ecological niche.

scholarly journals First results of the ORGANIC experiment on EXPOSE-R on the ISS

2014 ◽  
Vol 14 (1) ◽  
pp. 55-66 ◽  
Author(s):  
K.L. Bryson ◽  
F. Salama ◽  
A. Elsaesser ◽  
Z. Peeters ◽  
A.J. Ricco ◽  
...  
Keyword(s):  
Space Station ◽  
Extreme Case ◽  
Space Environment ◽  
Infrared Range ◽  
Continuous Exposure ◽  
Radiation Background ◽  
Particle Radiation ◽  
Spectral Changes ◽  
The Stability ◽  
Exposure Conditions

AbstractThe ORGANIC experiment on EXPOSE-R spent 682 days outside the International Space Station, providing continuous exposure to the cosmic-, solar- and trapped-particle radiation background for fourteen samples: 11 polycyclic aromatic hydrocarbons (PAHs) and three fullerenes. The thin films of the ORGANIC experiment received, during space exposure, an irradiation dose of the order of 14 000 MJ m−2 over 2900 h of unshadowed solar illumination. Extensive analyses were performed on the returned samples and the results compared to ground control measurements. Analytical studies of the returned samples included spectral measurements from the vacuum ultraviolet to the infrared range and time-of-flight secondary ion mass spectrometry. Limited spectral changes were observed in most cases pointing to the stability of PAHs and fullerenes under space exposure conditions. Furthermore, the results of these experiments confirm the known trend in the stability of PAH species according to molecular structure: compact PAHs are more stable than non-compact PAHs, which are themselves more stable than PAHs containing heteroatoms, the last category being the most prone to degradation in the space environment. We estimate a depletion rate of the order of 85 ± 5% over the 17 equivalent weeks of continuous unshadowed solar exposure in the most extreme case tetracene (smallest, non-compact PAH sample). The insignificant spectral changes (below 10%) measured for solid films of large or compact PAHs and fullerenes indicate a high stability under the range of space exposure conditions investigated on EXPOSE-R.

scholarly journals Detection of Contaminants in Hydrogen Fuel for Fuel Cell Electrical Vehicles with Sensors—Available Technology, Testing Protocols and Implementation Challenges

Processes ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 20
Author(s):  
Karine Arrhenius ◽  
Thomas Bacquart ◽  
Karin Schröter ◽  
Martine Carré ◽  
Bruno Gozlan ◽  
...  
Keyword(s):  
Quality Control ◽  
Standardized Testing ◽  
Chemical Sensors ◽  
Low Cost ◽  
Control Process ◽  
High Sensitivity ◽  
Low Carbon ◽  
Hydrogen Fuel ◽  
Quality Control Process ◽  
Testing Protocols

Europe’s low-carbon energy policy favors a greater use of fuel cells and technologies based on hydrogen used as a fuel. Hydrogen delivered at the hydrogen refueling station must be compliant with requirements stated in different standards. Currently, the quality control process is performed by offline analysis of the hydrogen fuel. It is, however, beneficial to continuously monitor at least some of the contaminants onsite using chemical sensors. For hydrogen quality control with regard to contaminants, high sensitivity, integration parameters, and low cost are the most important requirements. In this study, we have reviewed the existing sensor technologies to detect contaminants in hydrogen, then discussed the implementation of sensors at a hydrogen refueling stations, described the state-of-art in protocols to perform assessment of these sensor technologies, and, finally, identified the gaps and needs in these areas. It was clear that sensors are not yet commercially available for all gaseous contaminants mentioned in ISO14687:2019. The development of standardized testing protocols is required to go hand in hand with the development of chemical sensors for this application following a similar approach to the one undertaken for air sensors.

Conductive suit shielding properties assessment in different power frequency electric field exposure

2020 ◽  
pp. 835-836
Author(s):  
S. Y. Perov ◽  
O. V. Belaya ◽  
B. . Nemeth
Keyword(s):  
Electric Field ◽  
Field Exposure ◽  
Exposure Test ◽  
Shielding Factor ◽  
Power Frequency ◽  
Frequency Electric Field ◽  
Shielding Properties ◽  
Air Capacity ◽  
Field Strengths ◽  
Exposure Conditions

Shielding properties of conductive protective suits were tested by currents and power frequency electric field strengths for different exposure conditions. The differences between torso and head shielding factors, as well as shielding factors with and without face screen were determined. Near wire and in air capacity exposure test setups were the most valid for head shielding factor assessment.

COMPARING CRUDE OIL TOXICITY UNDER STANDARD AND ENVIRONMENTALLY REALISTIC EXPOSURES

1995 ◽  
Vol 1995 (1) ◽  
pp. 1003-1004 ◽  
Author(s):  
Charles B. Pace ◽  
James R. Clark ◽  
Gail E. Bragin
Keyword(s):  
Crude Oil ◽  
Real World ◽  
Petroleum Hydrocarbons ◽  
Oil Spills ◽  
Aquatic Toxicity ◽  
Total Petroleum Hydrocarbons ◽  
Toxicity Tests ◽  
Continuous Exposure ◽  
Dispersed Oil ◽  
Chemically Dispersed Oil

ABSTRACT Standard aquatic toxicity tests do not address real-world, spiked exposure scenarios that occur during oil spills. We evaluated differences in toxicity of physically and chemically dispersed Kuwait crude oil to mysids (Mysidopsis bahia) under continuous and spiked (half-life of 2 hours) exposure conditions. The 96-hr LC50s for physically dispersed oil were 0.78 mg/L (continuous) and >2.9 mg/L (spiked), measured as total petroleum hydrocarbons (TPH). Values for chemically dispersed oil were 0.98 mg/L (continuous) and 17.7 mg/L (spiked) TPH. Continuous-exposure tests may overestimate the potential for toxic effects under real-world conditions by a factor of 18 or more.

Dispersive Performance of Underwater Injection of Dispersant to Heavy Fuel Oil

2014 ◽  
Vol 2014 (1) ◽  
pp. 299045
Author(s):  
Shoichi Hara ◽  
Osamu Miyata ◽  
Takahiro Majima ◽  
Masao Ono ◽  
Hideyuki Shirota ◽  
...  
Keyword(s):  
Large Scale ◽  
Fuel Oil ◽  
Water Tank ◽  
Heavy Fuel Oil ◽  
Counter Measures ◽  
Mixed Sample ◽  
Black And White ◽  
Dispersed Oil ◽  
Oil Tank ◽  
Set Up

The National Maritime Research Institute started 5 year research project on the establishment of synthetic countermeasures against the discharge of oil and hazardous fluid substance from 2011 to 2015. The main purpose of this project is to produce the tool for the environmental risk assessment of the oil discharge from vessels which sank due to the marine accident. The element technologies as the counter-measure against the discharged oil will also be developed in the project. The element technology as sub-surface application of dispersant for counter-measures will be introduced at the poster session. The first large-scale application has been carried out during the Deepwater Horizon incident in gulf of Mexico in 2010. The experimental set-up consists of rectangular water tank (0.8m×0.8m×3.0m) connected to the oil tank and dispersant tank. The heavy fuel oil was used. Both oil and mixed sample of oil and dispersant have been discharged from the nozzle into the water tank. The video for the behavior of oil and mixed sample has been analyzed by defining the concentration of black and white color. The video has been taken by the high resolution camera. The concentration of 8 different steps between black and white was set in the analysis. The dispersed oil has particular color when dispersed in water and too much dispersant becomes clouded because the dispersant reacts to water. The concentration change has been related with the dispersive performance. The rising-up velocity was also analyzed by PIV (Particle Image Velocity) method so as to ensure the effect of the dispersive performance. The distribution of oil droplets has also been measured and analyzed. The various percentage of dispersant has been compounded into mixed heavy fuel oil. 1%, 5% and 10% dispersant oil ratio (DOR) has been tried in the experiment. The dispersive area and rising-up velocity after injection of both oil and mixed sample have been compared among them. The dispersive area and rising-up velocity due to difference of DOR has been discriminated. Those parameters can be an index of evaluating the dispersive performance.

REALTIME GEO-REFERENCED DETECTION OF DISPERSED OIL PLUMES

2005 ◽  
Vol 2005 (1) ◽  
pp. 693-696 ◽  
Author(s):  
Christopher B. Fuller ◽  
James S. Bonner ◽  
Frank Kelly ◽  
Cheryl A. Page ◽  
Temitope Ojo
Keyword(s):  
Real Time ◽  
Coast Guard ◽  
Ex Situ ◽  
Environmental Research ◽  
Time Lags ◽  
Corpus Christi ◽  
Dispersed Oil ◽  
Recent Developments ◽  
The U.S

The current SMART protocol used by the U.S. Coast Guard relies on traditional ex-situ fluorometers that require physical transport of the sample from the water column to the instruments. While sample transport methods are available (e.g. pumps and discrete sampling), they introduce time lags in the data acquisition process. These lags can be a source of error when the data is post analyzed and is not conducive to real-time monitoring efforts, creating significant logistical problems and dispersion (smearing) of the sample stream. Another limitation of the currently-used equipment is that it requires much attention to manually record GPS data which is later used to determine the spatial distribution of an oil plume. Recent developments of in-situ fluorometric instrumentation promise to simplify problems associated with deployment of ex-situ instrumentation (e.g. insuring that pumps are primed) in boat-based field applications. This study first compares the performance of two in-situ fluorometers in a simulated oil and dispersant application at the Shoreline Environmental Research Facility at Texas A&M University in Corpus Christi, Texas. The fluorometers were the WETStar and the ECP-FL3 (both by WETLabs, Inc.). To address issues related to data collection from a GPS and a fluorometer, a system was developed that simultaneously merges data from both instruments into a single file and presents the data real-time as a color-coded ship track. The applicability of this system was tested and evaluated during a spill response exercise conducted by the Texas General Land Office and the U.S. Coast Guard in Galveston Bay, Texas, U.S.A.

Sign in / Sign up

Export Citation Format

Share Document