Radio Activity Flashcards
(9 cards)
What are the sources of radioactivity in terrestrial ecosystems?
Man made: accidental release of nuclear power plants
Routine release of nuclear power plants.
Uranium and oil shale
firing of nuclear weapons
Radioactive waste deposits.
Natural
bedrock geology(granite)
Radon gas release by weathering
What are the three pathways for radiation exposure to human beings ?
Ingestion
inhalation
External exposure
What more can you say about the release of radiation ?
Radiation can either be released into the atmosphere or into water bodies .
Atmosphere: majority of its activity begins in the air(can be inhaled directly here) and is deposited by rain onto plants and the soil, which are then ingested by animal as /humans
Water bodies : activity is mainly in domestic water (can be ingested directly by humans here) , deposited in soils through irrigation(can be absorbed through external exposure) and then ingested by animals
True or false: food is one of the main ways radiation is ingested .
True
What are the most notorious food items that can pass on radiation.
Cow milk : takes a short time from the cow to humans ( a lot of pollutants may still be in it)
Cereals: rareLy undergoes any processing and takes a short time from production to consumers .
Mushrooms: the most susceptible to radiative substances ( because their surface can absorb large amounts). Food to game and humans.
Game meat : primarily eat food that are susceptible to radiation absorption.
True or false : what you eat determines how susceptible you are to ingesting radiative substances.
True
One of the important group of people who can contribute to radiation safety is ?
Farmers
How can farmers help to reduce radioactive substances in agricultural products.
Shielding : putting in preventative measures to stop further deposition of radioactive substances .could be to move livestock indoors or cover crops .
Waiting : radioactive decay is a natural process. With time radioactive substance concentration will decrease . This strategy involves waiting to harvest or, slaughter livestock till radioactive substance is minimal.
Removal and mitigation:
This can involve mixing substances like Cs-fixative which bind cesium reducing its availability for plant take up.
Deep ploughing and new sowing : buries contaminated soil layer deep then sowing on the new uncontaminated/less contaminated soil.
Washing and cooking produce can reduce some radioactive substance consumption.particularly surface contamination.
Fertilizing soil with potassium (K): potassium is chemically similar to Cesium and applying this will create a competition for plant uptake with cesium . This reduces accumulation of radioactive substance but this method relies on plant type/species and soil type.
What is the framework for developing a process based model to understand the accumulation of radionuclides in the environment. Eg TRACEY /COUP model.
Define the scope of your study , what particular agriculture product , system or environmental compartment is under study. You also have establish spatial (geographical area of the study)and temporal boundaries(the time period of the study . Will it be short or long term.
Pinpoint the sources of radioactive substances entering the system , is through the atmosphere. Ground water , or feed the organism must be eating .
Determine sinks where radioactive substances accumulate or can be e over from the system . Could be a specific compartment.
Track how the radioactive substance is moving in the said compartment and measure how much of the radioactive substance is present at the given time .
You have to account for interception by plants , wash off by rain , fixation in to tissues or cells, decay ( when the radioactive substance fades over time .
Develop scenarios of several potential situations and asses the effectiveness of counter measures ( eg deep ploughing and new sowing).
Test the model’s prediction against actual data and adjust as need to ensure accuracy.
