Biological Amplification What is it n Toxic pollutants

Biological Amplification What is it? n Toxic pollutants enter the ecosystem that are absorbed or ingested by organisms. Some substances accumulate in organism’s tissue over time.

Bioaccumulation An increase in the concentration of a pollutant in a biological organism compared to its concentration in the environment n It is how pollutants enter a food chain n

Biomagnification n Increase in the concentration of a pollutant as it passes from one trophic level to the next http: //www. tutorvista. com/content/biology-iv/ecosystem/biological-magnification. php

Biomagnification n Small amount in environment → Large concentration at top of food chain http: //www. tutorvista. com/content/biology-iv/ecosystem/biological-magnification. php

Why should we care? n Because the two processes together mean that when we release even small amounts of pollutants into the environment, eventually they build-up in organisms to toxic dosages http: //oceanservice. noaa. gov/educat ion/kits/estuaries/media/supp_estua r 09 a. html

Where do pollutants come from? Coal burning power plants n Factories n Farms, lawns, and gardens. n

Characteristics of pollutants: n In order for biomagnification to happen, substance must be: n Long lived n Soluble in fat n Mobile n Biologically active

Characteristics of pollutants: Putting it into perspective: n Only some substances biomagnify n Most substances are water soluble and are excreted into the water n Many breakdown quickly n Many are not biologically active

Ex. Biomagnification Water n Phytoplankton n Zooplankton n Small fish n Large fish n Top Predator: n Human, osprey, eagle, otter – highest amount of toxic chemical n http: //www. dc. peachnet. edu/~ccarter/Millerlec-12/sld 053. htm

Follow link to video n http: //happylibrarianblogspot. com/2008/ 01/biomagnification-video. html It can happen in terrestrial systems too!

Pollutants that undergo biomagnification n n Mercury Persistent organic pollutants (POPs)

Mercury Source: Emissions from coal-burning power plants, metal processing, medical and other waste n Refer to notes on deposition xx/xx n Made bioavailable by bacteria n Inorganic mercury → Organic form of mercury that is biologically active n

Mercury Elementary Mercury (Hg) n Methylmercury (CH 3 Hg) – most toxic form n Form ingested by consuming fish n Concentrated in muscle tissue n More in older fish than younger fish n Note – changed from Hg to this form by bacteria n

Where in the US is it a problem? Low p. H (acidic) lakes in Northeast and Northcentral US n Everglades (FL) n Certain Wetlands n Coastal wetlands along San Francisco Bay, Gulf of Mexico and Atlantic Coast n http: //sofia. usgs. gov/sfrsf/roo ms/mercury/food_chain/

Impacts of Wildlife Loons – diet of fish n Decrease in chicks in areas of high mercury n Large concentration of mercury in eggs n Great Egrets – study in Everglades indicates behavior of juveniles is effected n Deformities in developing animals n http: //www. usgs. gov/themes/factsheet/146 -00/

Risk to People Exposed by eating contaminated fish n Pregnant women and children most at risk n 60, 000 children born annually suffering from neurodevelopmental problems due to in utero exposure to mercury n http: //img. alibaba. com/photo/11388452/Frozen_Sushi. jpg

Fish Advisories 13 states have state wide advisories for fish from rivers and lakes n 40 states have advisories on selected bodies of water n Parts of Eastern Coast and Gulf of Mexico have advisories n

Concerned about the fish you eat? Recommendations per the FDA n Avoid shark, swordfish, king mackerel and tilefish = all are high in Mercury n 12 oz can be consumed a week of a variety of fish and shellfish that are lower in mercury. n Fish that are low in mercury are shrimp, canned light tuna, salmon, pollock, and catfish. n Note, albacore tuna has more mercury than canned light tuna. You may eat up to 6 oz of it in a week.

Concerned about the fish you eat? n Check out the Mercury calculator at http: //gotmercury. org/article. php? id=1034 n For information on Sustainable Seafood Choices check out Monterey Bay Aquarium and print out a pocket sized card http: //www. mbayaq. org/cr/seafoodwatch. asp

Origins of the term “Mad as a Hatter” Hg(NO 3)2 Mercury is a compound that was used to soften fur in the making of felt hats. n The phrase “Mad as a Hatter”, and the Mad Hatter of Alice in Wonderland -- both refer to the toxic effect of mercury on the central nervous system of the hat makers, producing mental effects and "hatter's shakes". n http: //www. ci. springfield. or. us/ Museum/Mad%20 Hatter%20 Te a%20 Party. jpg

Persistent Organic Pollutants (POPs) Also called organochlorines n Synthetic organic chemicals that persist in the environment and biomagnify through the food web n Poses a risk to human health and the environment Sources: n Pesticides, some plastics, paints, industrial chemicals, bleaching, burning garbage n Examples: DDT, PCBs, dioxin n

Ban on POPs 1995 UN estimated 20, 000+ substances with properties of POPs n Stockholm Convention 2004, banned 12 worst n “The Dirty Dozen” n U. S. signatory in 2001 n Congress has not ratified n Signed by n http: //www. nature. com/nrmicro/journal/v 4 /n 9/images/nrmicro 1498 -i 3. jpg

Stockholm Convention Treaty The Dirty Dozen 1. 2. 3. 4. 5. 6. DDT - pesticide PCBs - Industrial Dioxin - waste Furans - waste Aldrin - pesticide Chlordane - pesticide 7. 8. 9. 10. 11. 12. Dieldrin - pesticide Endrin - pesticide HCB – pest/ waste Heptachlor pesticide Mirex - pesticide Toxaphane pesticide

Exposure Environmental exposure – many will stay in soil or water for decades n Slow to breakdown n Humans consume toxins via fish, meat and dairy n

DDT (dichloro-diphenyl-trichloroethane) Insecticide used to control malaria and typhus by killing mosquitoes and lice. n Commonly used after WWII n Inventor received Noble Prize n Overused on crops as a pesticide n http: //commons. w ikimedia. org/wiki /Image: DDT_W WII_soldier. jpg http: //www. flahumforms. org/Florida. Dream/images/Th umbnails/1948 -Spraying-DDT-in-war-ag. jpg

Ex. DDT n Concentration of DDT increased 10 million times! http: //www. cfkeep. org/html/stitch. php? s=98965698293378&id=34347859802049

DDT problems Eggshell thinning n DDT interferes with metabolism of calcium n Result - thin shells in predator birds such as osprey, bald eagles, brown pelicans n Birds unable to brood (aka sit on) their eggs without breaking them www. ctaudubon. org/action/osprey. htm animals. nationalgeographic. com

DDT problems (cont’d) Feminization n Acts as a hormone disrupter, mimics estrogen n Has impacted sex ratio in some birds

DDT - it’s a long term problem n It has a half life of 15 year; it takes 15 yrs for its quantity to be ½ its original

DDT - it’s a long term problem It has a half life of 15 year; it takes 15 yrs for its quantity to be ½ its original n Ex. If we start with 100 kg, we will still have ~ 1 kg after 100 yrs n Year 0 15 30 45 60 75 90 105 Amount Remaining 100 kg 50 kg 25 kg 12. 5 kg 6. 25 kg 3. 13 kg 1. 56 kg 0. 78 kg

DDT current use Banned in US in 1972 n Still used overseas to prevent malaria n Estimated it save millions of lives annually in Africa n

POPs are everywhere! Even Polar Bears have POPs in their system n Top predator n All toxins in prey is transferred to them, stored in fat n Concentration increases 5 – 10 x each trophic level n http: //www. smh. com. au/ffxim age/2006/12/28/polar_bear_n arrowweb__300 x 387, 0. jpg

Health Impact of POPs Some cause cancer, damage nervous system n Some act like hormones (estrogens) leads to: n Developmental changes, birth defects n Reproductive and Behavioral problems n Toxins can be passed to young n

Thought to ponder n Even pollutants in small quantities can build up to toxic/lethal doses

Solutions to Toxic Pollution Worst ones are banned or no longer used in U. S. n Still need to eliminate/reduce the processes that create toxins (i. e. burning coal) n

Question of the Day Which group of pollutants is suspected to act like hormones (estrogens)? n Heavy metals n Persistent organic pollutants (POPs) n Inorganic plant nutrients n Organic oxygen-demanding wastes

http: //gotmercury. org/article. php? id=1034 n http: //www. seaturtles. org/article. php? list=type &type=75 n http: //www. ec. gc. ca/Science/sandemay 00/artic le 4_e. html n