Biomagnification and bioaccumulation

Question 1

What is bioaccumulation?

Answer 1

When an organism accumulates a material in its body at a concentration greater than the environment.

Question 2

What is biomagnification?

Answer 2

Occurs when bioaccumulation occurs in several links in a food chain. A consumer has to consume a lot of biomass from the lower trophic level. If that biomass contains the pollutant, the pollutant will be taken up in large quantities by the consume.

• long-lived (does not degrade and not easily broken down)
• concentrated in the organism’s body (not excreted)

Question 3

Uptake

Answer 3

The transfer of substances from the environment to plants, animals and humans.

Question 4

Ingest

Answer 4

The consumption of a substance by an organism.

Question 5

Storage

Answer 5

To put away for future use.

Question 6

Difference between bioaccumulation and biomagnification

Answer 6

Bioaccummulation describes how substances enter the food chain at the lowest trophic level
- Biomagnification describes the magnified effects or increasing levels of concentration of these compounds as they travel along the food chain/ trophic levels

Question 7

Ways to look for bioaccumulation

Answer 7

When material is long-lived (cannot degrade) or concentrated in the organisms body (cannot be excreted) the pollutants are soluble in fat.
Example- levels in sediments, plant tissue, water.

Question 8

Characteristics of DDT

Answer 8

• colourless, odourless, effective insecticide
• half life of 15 years (half effective as it used to be)
• not water soluble but fat soluble (taken up by fatty tissue)
• sub lethal- indirectly causes death
• accumulate toxin with each new feed

Question 9

What affect did DDT have on the peregrine falcon?

Answer 9

• high levels of DDT did not kill falcons
• chicks dropped dramatically
• shells on eggs were too thin- parents would break the paper thin shells
• affected hen’s ability to produce thick eggs shells
• indirectly killed chicks- killed them by preventing a strong shell from being produced

Question 10

How did the peregrine falcon accumulate so much DDT?

Answer 10

The peregrine falcons are top predators and absorbed large amounts of DDT from their prey- fish and other birds.

Question 11

What does it mean by broad spectrum pesticide?

Answer 11

• DDT is a broad spectrum pesticide.
• affects a broad range of pest species and not just the target species.
• DDT killed non- target species, new arrivals were free to replace original pests
• few survivor original pests develop resistance

Question 12

What is the Minimata disease?

Answer 12

Symptoms

• epilepsy
• neurological condition
• birth defects
• seizures and body convulsions

Question 13

The cause and source of Minimata disease

Answer 13

• Polluted airways
• Mercury poisons the central nervous system
• Transmitted through the intake of seafood
• Organic mercury compounds

Question 14

Why did the Chisso Corporation pay for the villagers to stop their fishing business?

Answer 14

Cheaper than safe disposal costs and possible future compensation claims.

Question 15

Why did the children and animals first affected by the toxin?

Answer 15

• There digestive systems were not as strong as the adults and the mercury was harder to degrade.
• Less biomass so more concentrated

Question 16

Why did the local residents welcome the arrival of Chisso Corporation?

Answer 16

• Gave Kumamoto residents jobs and business

- Created a multi-functional resource that could be used for multiple things (thermometer and electrical switches)

Question 17

Why did the research lead to two types of fish?

Answer 17

Those two fish are top carnivores and would contain higher concentration of toxins.
- Harder to digest/ excrete