Dioxins (Pcdd)

ENVIRONMENTAL COMPANY OF SAO PAULO STATE – CETESB

REGIONAL CENTRE OF STOCKHOLM CONVENTION ON POPs FOR LATIN AMERICA AND THE CARIBBEAN REGION

V INTERNATIONAL TRAINING PROGRAM ON ENVIRONMENTAL SOUND MANAGEMENT ON CHEMICALS AND WASTES, ESPECIALLY ON PERSISTENT ORGANIC POLLUTANTS (POPs) AND MERCURY (Hg)

Formation of unintentional Dioxin and Furan emissions and Mercury emissions into the atmosphere

PhD Ing. Ligia Cristina Gonçalves de Siqueira

2016 Sao Paulo – SP – Brazil DIOXINS (PCDD)

• Molecules formed of 2 benzene rings joined together by two oxygen atoms. •Withupto8Chlorineatoms,whichmay be in different positions in the molecule, replacing the hydrogen atoms. • 75 dioxin compounds in total. • 7 are considered toxic.

UNEP (2004) FURANS (PCDF)

• Molecules formed of 2 benzene rings joined together by 1 oxygen atoms and a C - C bond. • Withupto8Chlorineatoms,whichmaybe in different positions in the molecule, replacing the hydrogen atoms. • 135 furan compounds in total. • 10 are considered toxic

UNEP (2004) DIOXINS AND FURANS (PCDD/F) FORMATION OF PCDD/F

Contaminated - Material contaminated by PCDD/F combustible - Not eliminated by combustion material - Presence of precursors: PCBs, chlorinated Precursors phenols and chlorinated benzene. - Thermolysis and molecular rearrangement to form PCDD/Fs - Temperature: 250-450ºC

- Non-precursor compounds (no basis for formation): petroleum products, PVC, PS (polystyrene), cellulose, lignin, coke, Synthesis "again" coal, particulates (including fly ash). - Chlorine compounds (HCI) - Temperature: 250°C - 400°C

- Predominant in combustion systems - Occur outside combustion chamber - Reduction in temperature of gases and particles

FORMATION OF PCDD/F Thermal processes

• Availability of organic matter, oxygen and chlorine. • Reaction: – Need for chemical catalysts (enzymes) – Temperatures of around 200ºC to 400ºC • Formation: various types of process.

PNUMA (2007) FORMATION OF PCDD/F Elements FORMATION OF PCDD/F Synthesis pathways

• From precursors (such as chlorinated phenols) • Synthesis “de novo” (reformation): from carbonaceous structures in: – fly ash – activated carbon – soot – small molecules – incomplete combustion product

PNUMA (2007) FORMATION OF PCDD/F Synthesis pathways

• Incomplete combustion: can form PCDD/F. • Associated mechanisms: – Homogeneous: molecules react or all in the gas phase or all in the solid phase – Heterogeneous: reactions between gas phase molecules and surfaces.

PNUMA (2007) FORMATION OF PCDD/F Heat processes FORMATION OF PCDD/F

Main factors:

•Poor combustion : Technology •Post-combustion chambers and •Misoperated air pollution control devices

•Post-combustion zones or air pollution control devices: Temperature • Range: 200°C to 650°C – greatest formation: 200°C and 450°C – maximum point: ~ 300°C

PNUMA (2007) FORMATION OF PCDD/F Main factors: FORMATION OF PCDD/F Industrial chemical processes •Elements (same as thermal processes): •Carbon, hydrogen, oxygen and chlorine

•Favoured conditions: – High temperatures (>150°C) – Alkaline conditions – Metallic catalysts – Ultraviolet (UV) radiation or other radical starters

•Tendency to form PCDD/PCDF:

Chlorophenols > chlorobenzenes > aliphatic chlorides > inorganic chlorides

PNUMA (2007) BROMINATED DIOXINS /FURANS (PBDD/F)

- PBDDs: 75 types – 7 toxic - PBDFs: 135 types – 10 toxic Formation: - Chemical reaction - Photochemical - Thermal - Reformation (synthesis "again")

BRIGDEN and LABUNSKA (2009) WATANABE and SAKAI (2003) MIXED DIOXINS/FURANS

Formation: - Chemical reaction - Photochemical - Thermal - Reformation (synthesis “de novo")

BRIGDEN and LABUNSKA (2009) WATANABE and SAKAI (2003) Poly Chlorinated Biphenyls (PCBs) (dl-PCBS - Dioxin like PCBs)

•Aromatic compounds formed of one biphenyl molecule (2 benzene rings joined together by a C - C bond ). •Hydrogen atoms can be replaced by up to 10 chlorine atoms. •There are 209 PCB compounds in total. •13 are considered toxic.

UNEP (2004) dl - PCBs - Compounds that have physical and chemical properties and toxic responses similar to chemical structures 2,3,7,8- tetrachlorodibenzo-p-dioxin (PCDD). - Due to their hydrophobic nature and resistance to metabolism, these chemical substances persist and bioaccumulate in fatty tissues of animals and human beings.

More common health effects in people exposed to large amounts of PCBs: - Skin diseases, changes in blood and urine, liver disease. - Probably carcinogenic to humans (IARC) - D evelopmental or endocrine effects - Abnormal responses in tests of behavior (problems with motor skills and decrease in short-term memory) Poly Chlorinated Biphenyls (PCBs) (dl-PCBs - Dioxin like PCBs) Formation: - Thermal reaction of biphenyl group with chlorine in the presence of iron (as catalyst)

Some properties: - Particulate matter (> 5 atoms) and gases (up to 5 atoms) - Difficult combustion - Hardly biodegradable - Low volatility - Little solubility in water - Soluble in some organic solvents - High chemical stability - Decomposition at 300°C - Temperatures > 500ºC form PCDD/F

PENTEADO and VAZ (2001) MESQUITA (2004) TOXICITY EQUIVALENT (TEQ)

• Each dioxin has a different level of toxicity. • Most toxic: 2,3,7,8-TCDD (4 chlorine atoms at positions 2, 3, 7 and 8). • TCDD: means Tetra-Chloro-Dibenzo-Dioxin – Tetra: for 4 – Chloro: molecules of this substance – Dibenzo: 2 benzene rings – Dioxin: 2 oxygen molecules. • 210 dioxin and furan compounds in total (PCDD/F) • 17 are toxic or carcinogenic

PNUMA (2007) TOXICITY EQUIVALENT (TEQ) (Dioxin-like toxicity)

•The toxicity is different for each type and an equivalence system has been developed.

•For dioxin 2,3,7,8-TCDD (the most toxic) = toxicity value = 1.

•For others: a Toxic Equivalence Factor (TEQ) has been developed, which compares toxicity with 2,3,7,8-TCDD.

•Example: •Dioxin with TEQ of 0.001 is 1000 times less toxic than 2,3,7,8-TCDD. •Example: 250 ng of OCDD (Octa-Chloro-Dibenzo-Dioxin) •TEQ = 0.001 •Equivalent to TCDD = 0.001 x 250 = 0.25 ng of TEQ

PNUMA (2007) TOXICITY EQUIVALENT - PCDD/F TOXICITY EQUIVALENT - PCBs (Dioxin like toxicity)

Compounds WHO WHO USEPA (1997) (2005) (2010) PCBs 3,3’,4,4’-TCB (77) 0.0001 0.0001 0.0001 3,4,4’,5 – TCB (81) 0.0001 0.0003 0.0003 3,3’,4,4’,5 – PeCB (126) 0.1 0.1 0.1 3,3’,4,4’,5 ,5’- HxCB (169) 0.01 0.03 0.03 2, 3,3’,4,4’- PeCB (105) 0.00001 0.00003 0.00003 2, 3,4,4’,5 - PeCB (114) 0.00005 0.00003 0.00003 2, 3’,4,4’,5 - PeCB (118) 0.00001 0.00003 0.00003 2’, 3,4,4’,5 - PeCB (123) 0.00001 0.00003 0.00003 2, 3,3’,4,4’,5- HxCB (156) 0.00005 0.00003 0.00003 2, 3,3’,4,4’,5 - HxCB (157) 0.00005 0.00003 0.00003 2, 3’,4,4’,5,5’ - HxCB (167) 0.000001 0.00003 0.00003 2’, 3,3’,4,4’,5 - HpCB (189) 0.00001 0.00003 0.00003 Mercury •Found naturally in the earth's crust (air, soil and water).

- Metallic or elemental mercury (Hg) •Chemical forms - Inorganic mercury (e.g. mercuric salts (HgCl2, HgS) and mercurious (Hg2Cl2) - Organic mercury, linked to carbon radicals (e.g. methylmercury and ethylmercury).

- Metallic mercury: - Silver and shiny metal •Characteristics - Occurs in liquid state at room temperature - Easily volatilized into the atmosphere - Mercury vapors - colorless and odorless Mercury in the environment •Atmosphere - Main source of environmental contamination - Mercury vapor in the atmosphere: deposited in the middle or returns to the earth's surface with rain (soluble). - Emissions into the air (elemental form), highly stable and can remain in the atmosphere for months or even years, being transported across long distances around the world. - Can return to mercury vapor form and return to the atmosphere, or can be "methylated" by microorganisms in sediments of water, into methylmercury.

•Water and soil - Second source of environmental contamination, followed by soil contamination, when there is inadequate disposal of effluents and waste. - Remains in the environment, circulating between the air, water, sediment, soil and biota. http://www.ff.up.pt/toxicologia/monografias/ano0708/g1_mercurio/fisquim.html SOURCES OF AIR CONTAMINATION

All and any activities, processes, operations and mobile devices or which, regardless of their field of application induce, produce, or may produce air contamination, such as:

Industries Automobiles Machineries Open burning

State SP Law 997/76 NATURAL SOURCES (PCDD/F)

• Non-anthropogenic emission sources

USEPA (2004) NATURAL SOURCES (PCDD/F)

USEPA (2004) BIOGENIC SOURCES (PCDD/F)

• PCDD/F: can be formed freely in nature (soil, sediments, water), by the action of microorganisms, in forest fires and in the presence of sunlight. BIOCHEMICAL DEGRADATION

• Formation of PCDD/F from precursors,suchas chlorophenols, in the presence of microorganisms: • Sewage sludges –Due to contaminated effluents (RAPPE et al., 1989; 1994) –Aerobic treatment: less formation of PCDD / F (WEBER et al., 1995) • Compound (LAHL et al. (1991); KRAUSS et al. (1994)) –Presence of PCDD/F naturally in the soil or –Deposition in plants used for composting • Sediments and aquifer (BARKOVSKI and ADRIAENS (1995; 1996) –Slight reduction in concentration by biodegradation.

It is also possible for PCDD/PCDF to be biodegraded into chlorinated congeners. PHOTODEGRADATION (PHOTOLYSIS)

• Formation of PCDD/F from precursors in: • Action of sunlight on woods treated with pentachlorophenol (PCP) (LAMPARSKI, 1980). • Formation of PCDD/F from precursors in the air, water, soil and vegetation: require further studies. • Also an important mechanism for the destruction of PCDD/F. GEOGENIC SOURCES

• PCDD/F: can be formed freely upon eruption of volcanoes (incomplete combustion, high temperatures and presence of chlorine). MT. SAINT HELEN (USA)

• 1980 - Chlorinated aromatic compounds in ashes • 3 PCBs congeners • 1990 - Particulates free from PCBs and almost free from detectable PCDDs • Increase in PCBs and PCDDs in the ashes from rural and urban environments: associated with absorption of gases and agglomeration of particles GRIBBLE (1994) LAMPARSKI et al (1990) VOLCANOES: FUGENDAKE AND SAKURAJIMA (JAPAN)

TAKIZAWA et al. (1994) ANTHROPOGENIC SOURCES

• Emissions: Form as a consequence of human activities • However, in these cases formation is unintentional

Dibenzo-p-dioxins and polychlorinated PCDD/PCDF dibenzofurans Hexachlorobenzene HCB Pentachlorobenzene PeCB Polychlorinated biphenyls PCB

SIGNIFICANT ANTHROPOGENIC SOURCES: ANNEX C - PARTS 2 and 3

UNEP (2004) SOURCES OF COMBUSTION

Incinerators of waste (including co- incinerations of municipal, hazardous and medical waste, or sewage sludge).

Cement kilns that burn hazardous waste

Production of cellulose (use of elemental chlorine or chemical products that produce elemental chlorine for bleaching) UNEP (2004) METALLURGIC INDUSTRIES

Secondary copper production

Sintering plants (iron and steel industry)

Secondary aluminum production

Secondary zinc production UNEP (2004) OTHER SOURCES OF PCDD/F

Open burning of waste, including burning of effluents

Thermal processes in the metallurgical industry (not mentioned in Part 2) : -Secondary lead production -Primary aluminum production -Magnesium production -Secondary steel production -Primary production of common metals

Sources of domestic combustion (domestic wood burning stoves)

Combustion of fossil fuels in thermo- electric generation UNEP (2004) OTHER SOURCES OF PCDD/F

Specific processes for production of chemicals that release substances in Annex C (especially the production of chlorophenols and chloranil)

Facilities for combustion of wood and other biomasses as fuel

Crematoriums

Disposal of animal carcasses

Motor vehicles, especially those that use leaded gasoline as fuel UNEP (2004) OTHER SOURCES OF PCDD/F

Dyeing (with chloranil) and finishing (with alkaline extraction) of textiles and leathers

Fragmentation plants for vehicles not in use

Recovery of copper by smoldering cables

Re-refining of used oils

UNEP (2004) BROMINATED DIOXINS/FURANS

•Primary sources •PBDD/Fs: - Incineration - Recycling of plastics and metals from electronic devices - Final disposal of waste - Accidental fires - BRFs (brominated flame retardants): – Flame retardant factories – Plastic components (electronic devices) – Flame retardant foams

WATANABE and SAKAI (2003) DIOXINS LIKE PCBs (dl – PCBs)

•Other operations: Primary emission sources: •Accidents •Manufacture (products): •Inadequate handling •Dielectric fluids •Leakage from transformers, (transformers and condensers) capacitors and heat exchangers •Thermal fluids •Volatilization •Hydraulic fluids •Cutting oils and lubricants •Leakage of hydraulic fluids •Additives (adhesives, rubber •Inadequate storage of waste plasticizers, dyes and •Incineration pesticides) •Discharge of industrial effluents •Carbon paper and/or sewage in rivers and lakes. •Atmospheric dispersion

PENTEADO and VAZ (2001) Sources of Mercury Mobilization Impurity: -Fossil fuels: in mineral coal (higher level) and oil and gas (lower level) -Minerals: extraction, processing and recycled.

Origin: -Products and processes, used Waste intentionally -Production processes, fugitive emissions -Elimination and incineration of waste

Past anthropogenic releases: -Accumulated or deposited, at old sites, in soils, sediments, waters, landfills or waste deposits. Remobilization Sources of Mercury

•Gold mining •Chlor-alkali industries •Refining of oil and natural gas •Generation of energy (coal) •Medical-dental use (thermometers, pressure gauges, amalgam) •Lamps (fluorescent and Hg vapor) •Batteries •Electrical components OTHER FORMS OF CONTAMINATION - PCDD/Fs

• Application (war, agriculture) • Accidents • Food contamination • Areas contaminated by waste • Poisoning Vietnam War

• Agent Orange - 1960 (83 million liters) • Vietnam War • Defoliant for destruction of forests (advancing troops, destruction of enemies' food) • Product with TCDD (0.5 to 47 mg/kg)

PEREIRA (2004) Application in agriculture

• Pesticides (herbicides, insecticides, among others) • Protection of agricultural areas • Contamination of environment and the food chain. Contaminated foods

• Japan (1969) and Taiwan (1979) • Contamination of rice bran oil with PCB and furans due to leakage of heat exchanger using PCB as a thermal fluid.

PEREIRA (2004) Contaminated foods

• Germany – 2011 • High concentration of dioxins in eggs and animals • Animal feed with oil contaminated with dioxins • Oils for use in biofuels sold to feed producers • Destruction of eggs and animals. Contaminated feed

• Germany and several countries of the EC - 1997 • High concentration of dioxins in milk and butter • Citrus pulp pellets imported from Brazil for livestock feed • Contamination with dioxins, PCBs and chlorobenzenes due to treatment with lime before production (drying and neutralization). • Destruction of pellets (92000 t) PEREIRA (2004) Contaminated feed

• Belgium – 1999 • 500 t of feed for animals • 60 to 80 t of fat contaminated with ~50 kg PCBs from transforming oil and 1g from dioxins • Exported to France, Germany and the Netherlands • Exposure to 10 million people

PEREIRA (2004) ENVIRONMENTAL ACCIDENT

• Seveso Disaster (Italy) - 1976 • ICMESA Chemical industry • Rupture of reactor safety valve • Release of dioxins into the atmosphere • Contaminated area

PEREIRA (2004) Contaminated areas

• Brazil – Cidade dos Meninos (RJ) – 1989 • Hexachlorocyclohexane (HCH) Industry (1949-1959) • Illegal trade of HCH - reported in 1989 • Discovery of contaminated site close to the industry • Decontamination of HCH with lime: formation of dioxin PEREIRA (2004) POISONING

Source: http://lexicon.typepad.com/Yushchenko.jpg • Viktor Yuschchenko Poisoning - 2004 • Ukraine Parliamentarian OTHER FORMS OF CONTAMINATION - Mercury

• Application (medicine, agriculture) • Environmental Accidents • Food contamination • Areas contaminated by waste • Poisoning Application - Medicine and agriculture

• Pesticides (fungicides, insecticides, among others) • Dental amalgam • Protection of agricultural areas • Vaccine preservative • Contamination of environment and the food chain. Contaminated foods

• Iraq (1970s) • More than 6,900 people were hospitalized and at least 459 died. • Grains contaminated with methylmercury as pesticide.

Sources: http://cdcc.sc.usp.br/ciencia/artigos/art_32/aprendendo4.html http://cienciahoje.uol.com.br/especiais/rastros-do-mercurio/passado-e-tragedia Environmental accidents

Source: http://cienciahoje.uol.com.br/especiais/rastros-do-mercurio/passado-e-tragedia Environmental accidents

•Brazil – Rosana (SP) – 2011 •20 vials containing metallic mercury were abandoned on a plot of land •Children took these vials home •Contamination of 50 - 100 people •Decontamination of Hg with sulfur (school and hospital) Contaminated areas

• Minamata Bay (Japan) - 1976 • Vinyl chloride production industry • Projection of liquid effluent into the bay • Release of ethylmercury into the water • Contaminated area

Source: http://www.brasilescola.com/quimica/contaminacao-por-mercurio.htm Poisoning

• Poisoning - Akhmed Bilalov - 2013 • Leader of the Russian Olympic Committee ATMOSPHERIC DISPERSION

• Gas emissions released into the atmosphere: disperse throughout the environment. • Meteorological and topographical conditions: – Transport direction – Quantity – Diffusion

– Smoke configuration ETI (1992) ATMOSPHERIC DISPERSION

ETI (1992) DEPOSITION INTO THE ENVIRONMENT

• Deposition of gases and particles: soil and water (gravity, wind and precipitation). • Exposure: – Inhalation – Dermal – Ingestion (water or food ) • Prevent exposure: • Into the food chain. • Pollutants can cause chronic diseases or cancer.

ETI (1992) PROGRESS Identification of primary sources of POPs and Hg, such as: - Production of chlorinated agrotoxic substances - Waste incineration - Mines (gold) - Burning of fuels

Government actions: – Laws limiting emissions: POPs and Hg – Joint actions (such as identification of compounds, sources, management, training and global monitoring (matrices) and control) – Unification of conventions (Stockholm, Rotterdam, Basel and Minamata)

Further research on POPs and Hg (formation, characteristics, toxicity, etc.) -Identification of new compounds (like 9 new POPs) and new emission sources -PCDD/F and Hg control devices and monitoring NEW POPs USES Perfluorooctane sulfonic Surfactant and use acid (PFOS), its salts and in pesticides Perfluorooctane sulfonyl fluoride POPs USES Alpha- Agrotoxic Aldrin hexachlorocyclohexane Chlordane Beta- Agrotoxic DDT hexachlorocyclohexane Dieldrin Chlordecone Agrotoxic Pesticides Endrin Hexabromobiphenyl Flame retardant Heptachlor Hexabromodiphenyl ether Flame retardant Mirex and ether and Heptabromodiphenyl ether Toxaphene Lindane Repellent Hexachlorobenzene Industrial Pentachlorobenzene Agrotoxic, flame PCBs - chemicals and retardant and use Polychlorinated unintentional with PCBs in biphenyls substances dielectric fluids Dioxins Unintentional Tetrabromodiphenyl ether no information (By-products) Furans and Pentabromodiphenyl - (production, use ether and discharge) UNEP (2004) COP-4 (2009) REFLECTIONS

• Development of control devices and monitoring for compliance with international levels (better control technologies): – Particulate matter – Gases

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