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Nick Ling & Danica Hill. E- WASte. I <3 gadgets. When was the last time you bought a new computer, or a new cell phone? What happens to the old one?. http://www.slipperybrick.com/2008/01/star-trek-gadgets/.
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Nick Ling &Danica Hill E-WASte
I <3 gadgets • When was the last time you bought a new computer, or a new cell phone? • What happens to the old one? http://www.slipperybrick.com/2008/01/star-trek-gadgets/ http://www.unplggd.com/unplggd/green-ideas/recycle-your-cell-phone-and-donate-to-charity-041574
So, what’s e-waste? • E-waste is a term used for the recycling of electronic products such as • computers, • cellphones, • televisions, • VCRs , • stereos, • copiers, • fax machines, • and other electronic products that are no longer in use. http://deleket.deviantart.com/art/iPod-Generations-Icons-47813530?moodonly=1
Where does it go? • Developed countries don’t have the capacity to deal with the e-waste • So what do we do? • Send it to a third world country. http://www.greenpeace.org/international/campaigns/toxics/electronics/where-does-e-waste-end-up
Why send it away? • Expensive and difficult to process • Laws in the US and worker safety • Carcinogenicity of the materials • Problems? • Rapid technology change • Planned obsolescence • Think apple computers. Good for 3-4 years, then kaput! • Third world countries • Lack of environmental laws • Valuable metals in the electronics
Typical E-Waste Breakdown How much is discarded? • Disposed of in US (2007) • 205 million computer products • 27 million televisions • 140 million cell phones http://www.rubbermonkey.org/rothmobot/recycling.htm
What is the current problem? • This is the threat http://artsyspot.com/e-waste-in-guiyu/
Who’s playing the game? Stakeholders • Consumers (gadget buyers) • Countries exporting to developing countries • Workers • Producers/ manufacturers • Countries with properly established recycling facilities • People living next to the facilities
…1 Hazard Identification http://blog.archenemy.org/2006/10/15/proceed-with-caution-cognitive-hazard-ahead/
What’s the threat? • Aluminum, plastics, PCBs, zinc, flame retardants in plastics. • Toxic metals such as lead, mercury, cadmium • These materials can leak out into soil, water, and the atmosphere • Soil, water are needed for crops • People need air. (fresh) • Materials can lead to cancer, neurological and respiratory disorders , and potentially, birth defects. • Dust is generated in the mechanical and manual dismantling process • Inhaled into the system Hazard identification
Unsafe practices • Landfills • Incineration • Open Burning • Reuse • Recycling
Landfills • One of the most popular ways of waste disposal • This is problematic due to the materials reaching ground and water sources and contaminating them. Also a problem for developing nations who live in close proximity to landfills • Releases hazardous emissions such as Mercury, lead and cadmium. Also hazardous PCBs are released. • Landfills are prone to vaporization of toxix chemicals as well as uncontrolled that may spark.
Incineration • Very hazard due to the toxic fumes that are release and then inhales causing respiratory problems as well as skin problems • Copper which is used in circuit boards and cables acts as a catalyst for dioxin formation when flame retardants are incinerated • PVC also found in e-waste can be corrosive when burnt and lead to the formation of dioxins as well. • Leads to loss of useable elements that could have been sorted and recover properly
Open Burning • Releases more pulluntants that in a controlled incineration • When pollutants are inhaled it can cause asthma attacks, respiratory infections. Other smaller problems such as coughing, wheezing, chest pain and eye irritation • Open fires lack oxygen that then forms CO2 and when inhaled poisons the blood. • Inhalation of ash poses a problem as well.
Reuse, Recycling • Reuse • This is common for developing countries because they are inexpensive, however 25-75% of electronics are obsolete • Recycling • Mostly done in developing countries due to low recycling costs • Obtaining the raw materials from electronics can be profitable, however due to the hands on recycling, a worker’s health is at risk.
Who is at risk? • 3rdworlders • the workers • All ages. That includes children. • unborn babies • Toxins travel across the placenta • Aka. Mothers pass it on to the children. Hazard identification http://artsyspot.com/e-waste-in-guiyu/
Case Study: Guiyu, China One man’s trash is another man’s problem http://greenlightforbusiness.files.wordpress.com/2009/11/c99a16ed-eda3-47ef-8863-59670dd45d1f7.jpg
Guiyu • The largest E-waste recycling site in the world since the 1990s • This is where computers go to die • Population 150,000 and estimates ~ 80% of families engaged in the e-waste recycling program. • More problems? • Unsafe techniques – manual electronic component removal • Open burning to reduce mass, extract precious metals • Open acid digestion to recover precious metals
Contamination • Aquatic Systems – direct dumping of acid waste into streams • Soils – PDBE saturated soil • Genetic damage to plant and animal life. • Lead, cadmium in rice over 4 times in excess the maximum allowable concentrations. • Air • Dioxins – air particle concentrations: • 65-2765 pg / cubic meter* • remember, 65 pg/m^3.
Brush that dirt off your shoulder, now. http://4.bp.blogspot.com/_iVw4McXZboQ/Sxg1rsbHKCI/AAAAAAAAABM/5kZGn4XQzw4/s1600-h/guiyu.jpg
Precautionary Assessment Precautionary Assessment Precautionary Assessment
Precautionary Assessment summary • Community / Social Issues - 15/15 • Exposure Issues – 18/20 • Hazard / Toxicity – 28/30 • *precautionary assessment applies to the Guiyu, China case study.
Which one to narrow down to? • There sure are a lot of different chemicals. • We will focus on the burning of plastics, which releases toxic emissions such as: DIOXINS
What are dioxins • A class of hundreds of chemical contaminants • Most toxic is 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) • Formed during combustion processes such as waste incineration, forest fires. • The most potent synthetic carcinogen ever tested in laboratory animals
Dioxin, effects http://benblogged.com/wp-content/uploads/2007/10/zombie.jpg • Short term exposure • Chloracne- skin lesions • Hepatic toxicity- altered liver function • Long term exposure • Endocrine system • Reproductive functions • Animal studies • Cancer • Regarded as a probable human carcinogen, but conclusion is based off of animal studies and human epidemiological studies. Still debatable.
…2 Exposure assessment http://www.cynical-c.com/archives/bloggraphics/0421834.jpg
Daily Tolerable intake Dioxins. • WHO • 2 pg/kg bw/day • FDA • 0.03 pg/kg bw/day • EPA • 0.006 pg/kg bw/day • Canada • 10 pg/kg bw/day • Bw – body weight • Pg – Picogram = 10^-12 grams. A nanogram is 10^-9
Routes of exposure Dioxins • Inhalation • Air borne concentrations are high • 65-2765 pg / cubic meter • Dermal • Dust settling • Ingestion • Meat and dairy products • Beef, fish, eggs all bioaccumulate up the food chain • Levels are 100,000x of the surrounding environment • Breast milk
Choosing a human study • Hard to choose • Available human data not rigorous enough for establishment of a tolerable daily intake • Dioxins never travel alone in these studies. • confounding factors in exposure assessments.
We turn to animal studies • Most sensitive endpoint – developing reproductive systems of male rat fetuses while exposed in utero. • Measure effects on: • sperm production • Sperm morphology • Derive a Tolerable Daily Intake from this. • How? The sperm reserve in men is much less than a rat’s.
Study findings • Faqi et al (1998) • Lethality in animals: 1-5000 µg/kg • Reproductive – decreased fertility, decreased sperm count, teratogenic (birth defects) • Carcinogen – thyroid and liver tumors. Skin and liver cancer promotors
…3 Dose-Response Assessment
How to calculate risk? • Dioxins are usually found in mixtures containing several types of dioxins. • To express overall toxicity, use “international toxicity equivalents” (TEQ) • Individual dioxins are attributed their own Toxic Equivalence Factor (TEF)
1 0.1 0.0001 0.1 0.0001 0.1 0.01 Sample Toxic Equivalent Factors (TEFs) • 2,3,7,8-TCDD • 1,2,37,8-PeCDD • OCDD • 2,3,7,8-TCDF • PCB 77 (3,4,3’,4’) • PCB 126 (3,4,5,3’,5’) • PCB 169 (3,4,5,3’,4’,5’) Sum of these allows estimation of TEQs These are all types of dioxins, or dioxin-like compounds.
Considerations • Each chemical vary considerably • In tissue distribution and absorption • Metabolism • Elimination • Half-lives • In mice/rats may be only weeks • In humans may be 7+ years • TCDD – 7.5 years • OCDD – 120 years • In terms of risk assessment, need to take into account all of these factors.
Uncertainty factors Thus a 9.6 = uncertainty factor
calculations • Daily intake (pg/kg/day) = = body burden(pg/kg bw) x ln2 bioavailability x ½ life in days = 3400 pg/kg bw x 0.693 0.5 x 2740 days (7.5years) = 1.7 pg/kg/day • Uncertainty factor = 9.6 • LOAEL = 33* ng/kg/bw • Half-life in humans = 7.5 years • *LOAEL determined from Faqi et al (1998)
Many uncertainties • Dose-added is fundamental to the TEF model, sounds reasonable • But not certain that this is still applicable in complex mixtures related to human exposures and dose responses. • Most TEFs are derived from animal data • are they appropriate for humans? e.g. carcinogenicity
NOAEL, LOAEL • ATSDR: LOAEL: 120 pg/kg/day intake based on animal study. • Safety factor: 90. Yields tolerable intake of 1.3 pg/kg/day. • MRL set at 1 pg/kg/day. Serum lipid level associated with intake of 1 pg/kg/day is about 10 ppt, assuming 7.5 year half-life of elimination and 60 percent absorption. • WHO JECFA: Tolerable body burden: NOAEL/safety factor. • NOAEL: 16 ng/kg; Identified safety factor: 3.2 • Tolerable body burden: 16/3.2 = 5 ng/kg. • Corresponding serum lipid level: Assume 25% body fat: 5/0.25 =20 ppt • ECSCF: (European Commission Scientific Committee on Food) NOAEL body burden of 20 ng/kg; 3.2-fold safety factor. • Tolerable body burden: 20/3.2 = 6.25 ng/kg • Corresponding serum lipid level: Assume 25% body fat: 6.25/0.25=25 ppt tolerable serum lipid level • WHO (1998) level: Range of maternal body burdens associated with LOAELs in animal studies: 28-73 ng/kg. Identified safety factor: 10. • Tolerable body burden range: 28/10 to 73/10 = 2.8 to 7.3 ng/kg • Corresponding serum lipid level: Assume 25%body fat: 11-29 ppt range of tolerable serum levels http://www.dioxinfacts.org/dioxin_health/dioxin_food/dioxinTEQgraphic.pdf
Legislative mandates • No Federal mandate to recycle e-waste. • Many states have set up mandatory electronics recovery programs. • Disposal – Treated as hazardous waste
conclusion • Most people will not deal with dioxins from burning plastics. It is in food. • Don’t burn trash • LOAEL – 1.3 pg/kg daily • That’s 10 parts per trillion.
…4 Risk management and communication
What can we do. Prevention, solutions? • Basel Convention Multilateral environmental agreement • signed in 1992 by 169 countries to regulate trade of international trade of hazardous waste. • Basel Ban Amendment • adopted in 1995 outlawing the transfer of hazardous waste from developed countries to developing counties. • However it has not yet entered into full force other than some nations such as the European Union and China
solutions: E-stewards • A group of North American qualified and certified recyclers pursuing the highest standard of environmental and social responsibility when it comes to recycling electronic products • Ensure that e-waste products will no be dumped in landfills or incinerators, exported to developing countries or sent to prison labor operations • They will be accountable for all recycling processes for all of the toxic materials
Manufacturer responsibility • Have manufactures be responsible for the recycling of their specific products, this will lead them to make longer lasting and safe products
Proper Recycling • Detoxification • The removal of key components from e-waste materiasl that help to avoid dilution of contamination of toxic substances. • Examples: • Lead glass from CRT screens • CFC gases from Refrigerators, light bulbs and gases • Shredding • Obtaining recyclable materials as well as further separating out the hazardous materials • Also the gas emissions are filtered in this process to lower the environmental impact • Refining • The materials need to be refined and conditioned in order to be sold as secondary materials as well as being able to be properly disposed of in their final destination.