Presentation is loading. Please wait.

Presentation is loading. Please wait.

1-4-04 1-4-04 At least 11 million people in the U.S. currently drink water contaminated with arsenic at levels above 10 ppb, according to the U.S. Environmental.

Similar presentations


Presentation on theme: "1-4-04 1-4-04 At least 11 million people in the U.S. currently drink water contaminated with arsenic at levels above 10 ppb, according to the U.S. Environmental."— Presentation transcript:

1

2

3 At least 11 million people in the U.S. currently drink water contaminated with arsenic at levels above 10 ppb, according to the U.S. Environmental Protection Agency (EPA). From: Drinking Water Standard for Arsenic. U.S. Environmental Protection Agency, Office of Water, January At least 11 million people in the U.S. currently drink water contaminated with arsenic at levels above 10 ppb, according to the U.S. Environmental Protection Agency (EPA). From: Drinking Water Standard for Arsenic. U.S. Environmental Protection Agency, Office of Water, January 2001.arsenic Arsenic has been found in at least 1,014 of the 1,598 current or former sites on the National Priorities List (NPL), the most serious hazardous waste sites in the nation identified by the U.S. Environmental Protection Agency. Arsenic has been found in at least 1,014 of the 1,598 current or former sites on the National Priorities List (NPL), the most serious hazardous waste sites in the nation identified by the U.S. Environmental Protection Agency. Rule #1: Use phrases, not sentences. 6/6 Rule: No more than 6 bullets on slide, no more than six words per bullet. Rule #1: Use phrases, not sentences. 6/6 Rule: No more than 6 bullets on slide, no more than six words per bullet.

4 (är´senik) (är´senik) semimetallic chemical element semimetallic chemical element stable form: silver-gray, brittle crystalline solid, tarnishes rapidly in air. stable form: silver-gray, brittle crystalline solid, tarnishes rapidly in air. high temperatures burns white cloud of arsenic trioxide high temperatures burns white cloud of arsenic trioxide A yellow crystalline form and a black amorphous form are also known A yellow crystalline form and a black amorphous form are also known Rule #2: Use style checker; be consistent There’s an extra space before the A.

5 HISTORY HISTORY Used since 3000 B.C. Used since 3000 B.C. Arsenic mined by the early Chinese, Greek and Egyptian Arsenic mined by the early Chinese, Greek and Egyptian Albertus Magnus obtained the element in 1250 A.D. by heating soap and orpiment (arsenic trisulphide, As2S3) Albertus Magnus obtained the element in 1250 A.D. by heating soap and orpiment (arsenic trisulphide, As2S3) Element has an alchemical symbol Element has an alchemical symbol

6 Rule #3: Don’t overwhelm the audience

7 naturally occurring element naturally occurring element considered a heavy metal considered a heavy metal pure form not commonly found in the environment pure form not commonly found in the environment However, arsenic is found in natural and man-made compounds. However, arsenic is found in natural and man-made compounds. Rule #4: Use Spelling/Grammar Checker

8 About 90% of all arsenic produced is used as a preservative in wood (e.g., pressure-treated lumber). About 90% of all arsenic produced is used as a preservative in wood (e.g., pressure-treated lumber). which contains chromated copper arsenate (CCA). which contains chromated copper arsenate (CCA). Used in insecticides, Used in insecticides, weed killers, weed killers, fungicides, fungicides, glass production, glass production, semiconductors, semiconductors, to make metal alloys to make metal alloys some medications (mostly veterinary). some medications (mostly veterinary). Rule #5: Commas are unnecessary with bullets. No punctuation in a presentation

9 Various industries release arsenic into the air and groundwater Various industries release arsenic into the air and groundwater mines mines Smelters Smelters cotton gins cotton gins glass manufacturing operations glass manufacturing operations coal burning facilities coal burning facilities municipal incinerators municipal incinerators leach from landfills leach from landfills Rule #2: Be consistent, revisited

10 Once a treatment for Syphilis Once a treatment for Syphilis Experimental for leukemia Experimental for leukemia Taken in medication Taken in medication

11 A brownfield, by definition, is a poten- tially polluted and abandoned commer- cial and industrial site. A brownfield, by definition, is a poten- tially polluted and abandoned commer- cial and industrial site.

12 Brownfield Assessment of the Benton Auto Wreckers Site, Corvallis, Oregon 4-acre Benton Auto Wreckers site, located several miles southwest of the City of Corvallis on State Highway 20 in Benton County, Oregon

13 MARTIN MARIETTA ALUMINUM CO. OREGON EPA ID# ORD

14 897 ug/l Willbridge Bulk Fuel Area NW Doane AVE Portland 97210

15 REYNOLDS METALS COMPANY TROUTDALE, MULTNOMAH COUNTY, OREGON

16 What is arsenic? Arsenic is a natural element in the earth’s crust. Arsenic is a natural element in the earth’s crust. In the environment, arsenic combines with oxygen, chlorine, and sulfur to form inorganic arsenic compounds. In the environment, arsenic combines with oxygen, chlorine, and sulfur to form inorganic arsenic compounds. In animals and plants, arsenic combines with carbon and hydrogen to form organic arsenic compounds. In animals and plants, arsenic combines with carbon and hydrogen to form organic arsenic compounds. IARC has reviewed the available data and considers arsenic to be a Group 1 carcinogen. IARC has reviewed the available data and considers arsenic to be a Group 1 carcinogen. Rule #6: Let PowerPoint work for you. These are not proper bullets.

17 Basic Information Chemical Formula = C 6 H 8 AsNo 3 Chemical Formula = C 6 H 8 AsNo 3 CAS No = CAS No = Solubility = very soluble in hot water; slightly soluble in cold water, alcohol, and acetic acid; insoluble in acetone, benzene, ether, and chloroform. Solubility = very soluble in hot water; slightly soluble in cold water, alcohol, and acetic acid; insoluble in acetone, benzene, ether, and chloroform. Reactivity= condition contributing to instability varies depending on the specific organic arsenic compound. Reactivity= condition contributing to instability varies depending on the specific organic arsenic compound.

18 Exposure Limits OSHA PEL: The current OSHA permissible exposure limit for organic compounds arsenic (As) is:.5 milligrams per cubic meter or air as an 8-hour time weighted average concentration [29 CFR , Table Z-1] OSHA PEL: The current OSHA permissible exposure limit for organic compounds arsenic (As) is:.5 milligrams per cubic meter or air as an 8-hour time weighted average concentration [29 CFR , Table Z-1] ACGIH TLV: The ACGIH has not assigned organic arsenic compounds a threshold limit value. ACGIH TLV: The ACGIH has not assigned organic arsenic compounds a threshold limit value.

19 What are the common routes exposure to arsenic? Exposure to organic arsenic compounds can occur through inhalation, ingestion, eye or skin contact, and absorption through the skin. Exposure to organic arsenic compounds can occur through inhalation, ingestion, eye or skin contact, and absorption through the skin.

20 Health Effects Arsenic compounds are irritants, systemic toxins, and carcinogens in humans. Arsenic compounds are irritants, systemic toxins, and carcinogens in humans. Acute poisoning initial responses include; burning of the lips, constriction of the throat, and dysphasia. Acute poisoning initial responses include; burning of the lips, constriction of the throat, and dysphasia. Initial response is followed by excruciating pain in the abdominal region, severe nausea, vomiting, and diarrhea. Initial response is followed by excruciating pain in the abdominal region, severe nausea, vomiting, and diarrhea.

21 Health Effects Toxic effects on the liver, blood-forming organs, both central and peripheral nervous systems, and the cardiovascular system may also occur. Toxic effects on the liver, blood-forming organs, both central and peripheral nervous systems, and the cardiovascular system may also occur. Convulsions, coma, and death may follow within 24 hours of severe poisonings. Convulsions, coma, and death may follow within 24 hours of severe poisonings.

22 Health Effects Inhalation may damage the mucous membranes of the respiratory system. Inhalation may damage the mucous membranes of the respiratory system. Severe irritation of the nasal mucosa, larynx, and bronchi have been observed following exposure. Severe irritation of the nasal mucosa, larynx, and bronchi have been observed following exposure. Exposed skin may become irritated; cases of visual disturbances, hyper pigmentation of the skin, and perforation of the nasal septum have been noted. Exposed skin may become irritated; cases of visual disturbances, hyper pigmentation of the skin, and perforation of the nasal septum have been noted.

23 Health Effects Chronic exposure causes damage to the nervous and cardiovascular systems, also to the liver. Chronic exposure causes damage to the nervous and cardiovascular systems, also to the liver. Anemia and leukocytopenia have been reported to occur following chronic exposures to arsenic compounds. Anemia and leukocytopenia have been reported to occur following chronic exposures to arsenic compounds. Cancers of the skin, lungs, larynx, lymphoid system, and viscera have been identified as potential responses to arsenic poisoning. Cancers of the skin, lungs, larynx, lymphoid system, and viscera have been identified as potential responses to arsenic poisoning.

24 Measurement of Arsenic in Water Accurate measurement of arsenic in drinking-water at levels relevant to health requires laboratory analysis, using sophisticated and expensive techniques, facilities as well as trained staff not easily available or affordable in many parts of the world. Accurate measurement of arsenic in drinking-water at levels relevant to health requires laboratory analysis, using sophisticated and expensive techniques, facilities as well as trained staff not easily available or affordable in many parts of the world. Field test kits can detect high levels of arsenic bur are typically unreliable at lower concentration of concern for human health. Field test kits can detect high levels of arsenic bur are typically unreliable at lower concentration of concern for human health.

25 Protection From Exposure in a Commercial Setting Personal Protective Equipment: Workers should use PPE appropriately when working with organic arsenic compounds. The selection of the appropriate PPE’s should be based on the extent of the workers potential exposure. Personal Protective Equipment: Workers should use PPE appropriately when working with organic arsenic compounds. The selection of the appropriate PPE’s should be based on the extent of the workers potential exposure. In addition workers should wear uniforms or similar full body coverings that are laundered daily. In addition workers should wear uniforms or similar full body coverings that are laundered daily.

26 Protection From Exposure in a Commercial Setting Respiratory Protection: Respirators must be worn if the ambient concentration of organic arsenic compounds exceeds prescribed exposure limits. Respiratory Protection: Respirators must be worn if the ambient concentration of organic arsenic compounds exceeds prescribed exposure limits. Workers should only use respirators that have been approved by NIOSH and the Mine Safety and Health Administration (MSHA) Workers should only use respirators that have been approved by NIOSH and the Mine Safety and Health Administration (MSHA)

27 EPA Regulations Regarding Arsenic The EPA has set limits on the amount of arsenic that industrial sources can release to the environment and has restricted or canceled many of it’s uses in pesticides. The EPA has set limits on the amount of arsenic that industrial sources can release to the environment and has restricted or canceled many of it’s uses in pesticides. The EPA published a final rule on January 22, 2001 revising the existing arsenic drinking water standard from 50 parts per billion to 10 parts per billion, with a compliance date of January The EPA published a final rule on January 22, 2001 revising the existing arsenic drinking water standard from 50 parts per billion to 10 parts per billion, with a compliance date of January

28 There are currently 9 general processes I. Oxidation II. Coagulation/Co-precipitation III. Sedimentation IV. Filtration V. Adsorption VI. Ion Exchange VII. Membrane/ Reverse Osmosis VIII. Biological IX. Other Arsenic Remediation Arsenic Remediation Rule 7: Use features to enhance the presentation, not run the show

29 Of the two predominant forms of arsenic in water, arsenate and arsenite, most treatment processes are effective at removing arsenate, but not arsenite, since arsenite is typically non-charged below pH 9.2. Therefore, treatment for the removal of arsenic often includes an oxidation step to convert arsenite to arsenate. Oxidation can be simply the addition of oxygen to a compound, or more generally, any reaction involving the loss of electrons from an atom. Aeration, the supplying of air, oxidizes arsenic, converting arsenite to arsenate, and the iron that co-occurs. This is precipitated as FeAsO4. Arsenic can also be oxidized by a number of other chemicals including chlorine, hypochlorite, ozone, permanganate, hydrogen peroxide and Fenton’s reagent (H 2 O 2 /Fe 2+ ). Photochemical oxidization proceeds from the reaction of radiant energy and a chemical system. Oxidation alone does not remove arsenic from solution but must be combined with an arsenic removal process. 1. Oxidation

30 2. Coagulation/Co-Precipitation Coagulation involves the removal of colloidal ( microns) and settleable (> 100 microns) particles. Co—precipitation: incorporation of soluble arsenic species into the metal hydroxide floc. Coagulation encompasses all reactions, mechanisms and results in the overall process of particle growth (floc formation) and particle aggregation within a water being treated.

31 converts soluble arsenic into insoluble reaction products, allowing separation by sedimentation and/or filtration. * Precipitation: the formation of insoluble compounds Al(AsO4) or Fe(AsO4) * Co—precipitation: incorporation of soluble arsenic species into the metal hydroxide floc * Adsorption: the electrostatic binding of soluble arsenic to the external surfaces of the insoluble metal hydroxides Coagulation

32 1. Inclusion: mechanical entrapment of a portion of the solution surrounding the growing particle. 2. Adsorption: the attachment of an impurity onto the surface of a particle or precipitate. 3. Occlusion: A contaminant is trapped in the interior of a particle of precipitate. 4. Solid-solution formation: another type of occlusion where a particle of precipitate becomes contaminated with a different type of particle that precipitates under similar conditions and is formed from ions whose sizes are nearly equal to those of the original precipitate. There are 4 types of co-precipitation:

33 Sedimentation is the gravity separation of solids from liquid by settling. It is generally used in conjunction with coagulation/precipitation 3. Sedimentation

34 Conventional filtration is the separation of solid particles from water by passing the solution through a medium. Particles are removed during filtration as a result of any one or combination of mechanisms: mechanical straining, sedimentation, flocculation,adsorption and/or biological metabolism (AWWA, 1999). 4. Filtration

35 Adsorption is the accumulation of materials at an interface, the liquid/solid boundary layer. * oxides (e.g. hydrated ferric oxide, titanium oxide, silicon oxide); * iron oxide -coated or MnO 2 -coated sand; * bauxite, hematite, feldspar; * clay minerals (e.g. kaolinite, bentonite, Bijoypur clay); * synthetic anion exchange resins; * chitin and chitosan; * bone char; * cellulose materials (sawdust, newspaper pulp). 5. Adsorption

36 Ion exchange is the reversible interchange of ions between the solid and the liquid phase where there is no permanent change in the structure of the solid. Developed for large-scale applications, ion exchange is probably not appropriate for small hand ‑ pumped wells, but could potentially be used on a village scale in Bangladesh Charged functional groups are attached to the matrix through covalent bonding and fall into four groups (Clifford, 1999) Strongly acidic Weakly acidic Strongly basic Weakly basic 6. Ion Exchange

37 Membrane separation uses semi-permeable membranes that are selectively permeable to water and certain solutes to separate impurities from water Membranes are able to remove many different kinds of dissolved solids, including arsenic, from water. However, they are usually expensive and therefore are typically considered in applications such as desalination, brackish water conversion and for removal of specific ions, such as arsenic, that are difficult to remove by other means 7. Membrane/Reverse Osmosis

38 Biological treatment transforms, stabilizes and/or removes arsenic by means of microorganisms. Microorganisms, primarily certain specific bacteria, accomplish this by oxidation/reduction, mineralization,detoxification or methylation. Critical factors include energy and carbon source; aerobic, anoxic or anaerobic conditions; temperature; pH 8. Biological

39 Dug Wells Deeper Tube Wells Ponds Solar Distillation Solar distillation uses the sun's energy to evaporate water, which then recondenses. The process of evaporation and recondensation separates all chemicals, including arsenic, from the water. In Bangladesh,where solar energy is plentiful, this approach may be especially suited for application in crisis areas, and, if cost- effective approaches can be developed, in rural are as generally. 9. Other

40 What Does It Cost? A Home System $150 to $ A Large Industrial System to Clean Up Treated Wood Waste $1,080,000+

41 1.Oxidation 2.Precipitation 3.Filtration and Removal Point Of Use- POU- Home Filter Systems Arsenicfilters.com display Rule #8: Pictures/Graphics are great. Show them, don’t tell them

42 Contaminants: Chromated Copper Arsenate (CCA) Cost: Full Scale plant capable of treating 100 tons/day of CCA contaminated waste wood will cost around $1,000,000 Other Applications: Remediation of Metal contaminated soil, sludge and other debris Secondary Waste: None Operating Cost: It will cost between $120 to $150 /ton for remediation of of CCA contaminated wood in a 100 ton/day plant West Central Environmental Consultants, Inc Can Provide A Complete Cleanup Plant for Arsenic Treated Wood facilities. Tech Know New Remediation Technologies Rule #9: KEEP IT SIMPLE (KIS) No more than 2 colors in a show; No more than 2 fonts or font sizes on a slide. Rule #9: KEEP IT SIMPLE (KIS) No more than 2 colors in a show; No more than 2 fonts or font sizes on a slide.

43 State Average Arsenic Concentrations for Systems Finding Arsenic Based on best estimate of average arsenic levels for systems that found arsenic. USGS

44

45 MIT Arsenic Remediation Technologies: Online Informational Database 1. Clifford, D “Ion Exchange and Inorganic Adsorption. In: Letterman {Ed]. Water Quality and Treatment, 5 th Edition. American Water Works Association, McGraw Hill, New York. 2. Johnston, R. and Heijnen, H “Safe Water Technology for Arsenic Removal.” In: Ahmed, M.F. et. al. [Eds]. Technologies for Arsenic Removal from Drinking Water. Bangladesh University of Engineering and Technology, Dhaka. Bangladesh REFERENCES Page 1. GETF Networks GETF Networks are a collection of the Internet's most visited environmental, energy and technology communities.... arsenicfilters.com

46 Disclaimer We certify that all information contained herein is true and accurate to the best of my knowledge and information. This information is applicable only to, and for use only by the students of the Environmental Health and Safety Program, Mount Hood Community College. Any use of this information by other parties, including without limitation, the subject facility, without the express written permission of all participating students, will be at that party’s sole risk, and the students, faculty and staff of Mount Hood Community College Shall have no responsibility therefore. The existence and use of this report by ANY PERSON OR ORGANIZATION Shall not be deemed an admission of evidence of any responsibility by the students, faculty or staff of Mount Hood Community College. We certify that all information contained herein is true and accurate to the best of my knowledge and information. This information is applicable only to, and for use only by the students of the Environmental Health and Safety Program, Mount Hood Community College. Any use of this information by other parties, including without limitation, the subject facility, without the express written permission of all participating students, will be at that party’s sole risk, and the students, faculty and staff of Mount Hood Community College Shall have no responsibility therefore. The existence and use of this report by ANY PERSON OR ORGANIZATION Shall not be deemed an admission of evidence of any responsibility by the students, faculty or staff of Mount Hood Community College. Know the proper spelling of organizations

47 Rules to Remember x6 Rule 2. 2.Proofread and use Style Checker 3. 3.Don’t overwhelm the audience 4. 4.Use Spelling/Grammar Checker 5. 5.No punctuation in a presentation Let PowerPoint work for you Use features to enhance the show, not be the show Show them, don’t tell them KIS Rule


Download ppt "1-4-04 1-4-04 At least 11 million people in the U.S. currently drink water contaminated with arsenic at levels above 10 ppb, according to the U.S. Environmental."

Similar presentations


Ads by Google