biomagnification & bioaccumulation_2

Lora Kyulaflieva

Nikolina Yankova

Martin Maksimov

Content

Bioaccumulation Biomagnification Bioaccumulation vs Biomagnification What types of substances

bioaccumulate and which do not? Concentration of DDT in tissue Concentration of mercury in fish

Bioaccumulation Def: accumulation of substances in the

environment, before they are taken in by the first organism in a food web (1)

The accumulation of organic chemicals in an organism (1)

Substances enter through epidermal contact or other processes (2)

Result: The concentration of the substance in the organism is > then the one in the environment (2)

Bioaccumulation Bioaccumulation

depends on many environmental, biological and physical factors (3)

More hydrophobic subst. =>more likely to bioaccumulate (4)

ex. Methlymercury Bioconcentration-

refers to the uptake only of water (2)

”Madd as a hatter”

Affinity for fat Not soluble in water (3)

Low biodegradability (2)

First-generation organochlorine pesticides (e.g., DDT, chlordane, and toxaphene), PCBs, dioxins, brominated flame retardants and some organo-metal compounds (3)

Bigger molecules can not bioaccumulate (6)

Which substances bioaccumulate?

BiomagnificationThe tendency of pollutants to become concentrated in successive

trophic levels

Stage 1 (5)

Producers need inorganic nutrients

Pollutants resemble inorganic nutrients and producers take them

Result – higher concentration of pollutant in the producer than in the environment

Stage 2 (5)

Occurs when the producer is eaten

Pollutant stored and absorbed in the body of the consumer

Build up in the fatty tissue of the consumer

Result – pollutant can not leave the body of the consumer

Biomagnification Conditions:1.The pollutant must be long-lived. 2.The pollutant must be concentrated by the producers. 3.The pollutant must be fat-soluble. (5)

Which substances biomagnify?

Novel organic substances – POPs

Some metals – Mercury, Cadmium (6)

Effects of Biomagnification:

Detrimental Most dangerous for predatorsPolar bears, humans, eagles, and dolphins – top predators (6)

To ease up magnification >>>

Bioaccumulation vs Biomagnification

Both describe the increase of the amount of a substance in an organism (1,3)

Bioaccumulation occur within a single organism (1)

Biomagnification occurs across trophic levels (3)

Concentration of DDT in tissue•How does it occur – persistent and lipid soluble •How does it pass through a food chain (4)

•Used as a pesticide – from insects to fish, birds and then larger animals (5)

Concentration of mercury in fish

Fish absorb mercury efficiently – don’t excrete it (4)

Larger the fish – more the mercury

Some have been banned for (4)

consumption for they present a risk of intoxication (5)

Works cited

1. "Bioaccumulation". Wikipedia. 13.06.2010 <http://en.wikipedia.org/wiki/Bioaccumulation>.

2. "Bioaccumulation". Toxics US Gov. 13.06.2010 <http://toxics.usgs.gov/definitions/bioaccumulation.html>. http://www.marietta.edu/~biol/102/2bioma95.html

3. "Biomagnification and Bioaccumulation". Tripod. 13.06.2010 <http://domchemct.tripod.com/index.html>. http://wiki.answers.com/Q/Example_of_biomagnification

4. "Biomagnification". 13.06.2010 <http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/D/DDTandTrophicLevels.html >. http://www.dowcorning.com/content/publishedlit/01-1128-01.pdf

5. "Environmental Biology - Ecosystems ". 13.06.2010 <http://www.marietta.edu/~biol/102/ecosystem.html>. http://www.pollutionissues.com/A-Bo/Bioaccumulation.html

6. "Food Chain/Biomagnification". 13.06.2010 <http://science.jrank.org/pages/2801/Food-Chain-Web-Biomagnification.html>.