Font size
WorksheetsAcute and Chronic Toxicity
Total questions: 18
Worksheet time: 16mins
Acute (a) toxicity is associated with rapid change in concentration in an organism often related to a spill, accident, plant malfunction, or seasonal pulse.
Acute (a) -defined toxicity typically involves laboratory studies with well-defined contaminants (or mixtures) and conditions with outcomes such as LD50 or LC50 values.
What are the important elements in the article title (in the image) that make this an informative toxicity paper?
Chemical used in test
Life stage of organism
Exposure time
Biological focal area of test
Do you think toxicology should abandon the use of the terms acute and chronic?
Yes. Provide exposure time and developmental stage instead.
No. It's too late to change and the alternatives are no better.
It does not matter as long as the goal stays the same "to provide data to establish biologically safe concentrations of toxicants in the environment."
I have no idea what you're talking about.
Contaminant-organism response (between organisms for same or similar contaminant) can include the following types of variations: (Check all that apply.)
Long-term acclimation
Short-term resistance
Temporal variation
Response (more or less severe)
Life-length and regeneration time
General Stress Response (GSR) is generally associated with an (a) response to contaminants.
General Stress Response (GSR) can be associated with.... (Select all that apply.)
caging/container exposure
change in conditions (e.g. water properties)
handling stress
contaminant
What approach can be used to separate toxic effects from a general stress response?
Collect the same data for the same contaminant from lots of different species under the same conditions
Collect the same data for chemicals with completely different MOAs for the same species under the same conditions
You cannot separate GSR from acutely toxic effects
_________-_________ alternatives (e.g., moving equipment where organism exposure can be done) can help reduce GSR, but can be challenging in field conditions.
(a)
It is typical to see temporal differences in contaminant response from different biomarkers.
True
False
Time courses of contaminant response can be _________. (Select all the apply.)
Immediate (e.g., qPCR to measure transcriptional effects)
Transitory (immediate, but short-term, eg., GSR)
Delayed / Prolonged (e.g., genotoxicant changes to DNA)
Evaluating (a) toxicity is necessary for ecological risk assessment to estimate risk and develop environmental quality standards based on values such as PNEC, EC50, NOEL/LOEL.
NOEL / LOEL stands for what?
No obvious effect level / longest observed effect level
No observed effect level / lowest observed (adverse) effect level
No observed effectiveness limit / limited obvious effectiveness level
For chronic toxicity, sublethal parameters (e.g., reproductive toxicity) are important.
True
False
For chronic toxicity assessment, response is not dependent on developmental-stage.
True
False
Determining chronic toxicity can be complicated by environmental factors and mixtures.
True
False
The OECD provides species-specific guidance on toxicity test duration, survival, and other test criteria.
True
False
Did you enjoy and learn from the 'guest video speaker' presenting on Coho Salmon and Tire Contaminant?
Yes. You should show it to future classes - very interesting!
No. Talk was too technical for me to understand.
Yes, but you need to provide more background on the toxicity tests used in the study to make it relevant to the class.
No. I don't think it is a valuable use of class time, but maybe make the video available for students online.
