Bioaccumulation and Biomagnification What are they Poisons What

Bioaccumulation and Biomagnification

What are they? Poisons

What are Poisons? Poisons are substances that cause damage to organsisms Toxins - poisons produced within living cells A few examples of poisons in your homes are: ◦ Drain Cleaner ◦ Gasoline ◦ Battery Acid

What are biodegradable and nonbiodegradable substances? Biodegradable substances are naturally broken down in the environment. eg sewage (feces and urine), dead organisms. Non-biodegradable substances are broken down very slowly or not broken down at all by natural processes. eg plastics, pesticides

Bioaccumulation & Biomagnification What is it?

Bioaccumulation � Accumulation of a pollutant substance within an organism � Bioaccumulation occurs when the pollutant is absorbed by the organism faster than it is lost. � Usually of substances that are nonbiodegradable � e. g. Grass absorbing pesticides over time.

Biomagnification is the result of bioaccumulation, where pollutant substances become more and more concentrated moving up the food chain. Also referred to as bioamplification.

How it Works Only 10% of energy is passed from one trophic level to another. This means a species has to eat a large amount of the species below it to survive. The species receives all of the pollutants contained in all of the organisms it consumed. The pollutant is therefore more concentrated in the bodies of that species.

Process of Bioaccumulation 1. There are many ways chemicals end up in lakes and rivers, including wind and rain run-off. 2. The chemicals sink to the bottom of the lake or river, where they settle in the sediment. 5. Larger fish, predator fish, and longer living fish are likely to have more chemicals in their bodies than smaller, younger fish. Check the Eat Safe Fish Guide to find safe fish. 3. Small creatures, called macroinvertebrates, eat these chemicals as they dig in the sediment for food. 4. The macroinvertebrates are eaten by minnows, minnows by medium-sized fish, and those fish are eaten by large fish - each collecting and storing some of the chemicals in their bodies.

Animation http: //sciencelearn. org. nz/Contexts/Toxins/ Sci-Media/Interactives/Bioaccumulation-inthe-sea

Biomagnification � DDT ◦ ◦ Pesticide used in the 1900 s. (synthesized 1948) Banned in 1972. Seemingly harmless at first. Effects began showing up in high trophic levels because of biomagnification.

Mercury in fish https: //www. youtube. com/watch? v=Q 1 ZA 8 Zr K 3 U 4

Problem with Mercury can be converted to methyl mercury (highly toxic) mainly in lakes, waterways and wetlands. If water plants and small organisms take up the mercury, it then moves through the food chain when animals eat each other. Methyl mercury can cross the blood-brain and placental barriers that can lead to a wide range of symptoms in organisms. Have you heard of Mad hatters?

**Google Search Polyethylene

PCBs Can cause cancer Polychlorinated Biphenyls