Toxicants Flashcards
What is an environmental hazard?
Situations or events that pose threats to surrounding environment and human health
Environmental hazards can include natural disasters, pollution, and industrial accidents.
Define toxicant.
Chemical released into environment that can pose environmental hazards to humans and ecosystems
Toxicants can be naturally occurring or man-made substances.
What is toxicology?
Study of toxins
Toxicology examines the effects of harmful substances on living organisms.
What does ‘acute’ refer to in toxicology?
Short term, high dose
Acute exposure can lead to immediate health effects.
What does ‘chronic’ refer to in toxicology?
Long term, low dose
Chronic exposure can lead to long-lasting health effects.
What is a key finding from the 1960’s Grassy Narrows case study?
90% of Grassy Narrows members suffer from mercury poisoning in 1990
This case highlights the long-term effects of environmental contamination.
What percentage of Grassy Narrows members suffer from mercury poisoning today?
50%
This indicates ongoing issues with mercury contamination.
What are persistent toxicants?
Chemicals that resist breakdown from natural processes
These toxicants can accumulate in the environment and pose long-term risks.
How do persistent toxicants move through the environment?
Rapidly move environments and are dispersed through water, air, and soil.
Their mobility increases the potential for widespread environmental contamination.
Name a type of persistent organic pollutant (POP).
Pesticides
POPs are known for their long-lasting effects and ability to bioaccumulate.
Give examples of heavy metals that are toxicants.
Lead, mercury
Heavy metals can have severe health impacts and are persistent in the environment.
What is an example of a radioactive isotope that is considered a toxicant?
Cesium 137
Radioactive isotopes can pose significant health risks due to radiation exposure.
What are microplastics?
Small plastic particles that can act as toxicants
Microplastics can accumulate in ecosystems and enter the food chain.
Fill in the blank: Dilution is the _______.
Solution
This phrase is often used in discussions about managing pollution.
What is long-range transport in environmental science?
Movement of pollutants over long distances through environmental pathways
This can lead to contamination in areas far from the source.
What does persistence mean in relation to toxicants?
Toxicant that is chemically stable and takes years to break down into a less toxic form
Persistent toxicants can have long-term environmental and health effects.
What is environmental fate?
Refers to downstream impact of toxicants
This concept includes how toxicants affect ecosystems and human health over time.
Define bioaccumulation.
Build-up of toxicants in an organism’s body
Organisms can accumulate toxicants faster than they can eliminate them.
What is bio-magnification?
Increase in toxicant concentrations as a toxicant passes through successive levels of the food chain
Higher trophic levels may experience significantly higher concentrations of toxins.
How do toxins generally occur in the environment?
In low concentrations, then increase as the food chain occurs
This phenomenon highlights the risk of high concentrations in top predators.
