biphenyl by ashley register. overview structure, chemical & physical properties uses and...
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OverviewOverview
• Structure, Chemical & Physical Properties
• Uses and Applications• Production History• Mode of Entry• Chemical Reactivity and Speciation• Toxicity to Aquatic Life• Biochemical Metabolism• Bibliography
• Structure, Chemical & Physical Properties
• Uses and Applications• Production History• Mode of Entry• Chemical Reactivity and Speciation• Toxicity to Aquatic Life• Biochemical Metabolism• Bibliography
PropertiesProperties
• 1,1’-biphenyl, diphenyl, phenyl benzene
• Chemical and Physical Properties:– Kow: 4.09– Water Solubility: 7.1 mg/L at 25oC– Henry’s Law Constant: 3E-4 atm
m3/mol
• 1,1’-biphenyl, diphenyl, phenyl benzene
• Chemical and Physical Properties:– Kow: 4.09– Water Solubility: 7.1 mg/L at 25oC– Henry’s Law Constant: 3E-4 atm
m3/mol
Hazard ClassificationHazard Classification
• Classifed as:• EPA:
– Class D carcinogen (not involved in human carcinogenesis)
– Non-teratogenic• EU:
– Irritant (Xi)– Dangerous for the environment (N)
• Classifed as:• EPA:
– Class D carcinogen (not involved in human carcinogenesis)
– Non-teratogenic• EU:
– Irritant (Xi)– Dangerous for the environment (N)
Uses and ApplicationsUses and Applications
• Dye Carrier for Textile dying• Intermediate for PCB’s and PBB’s• Fungicide for citrus fruits• Major component of Heat Transfer
Fluids
• Dye Carrier for Textile dying• Intermediate for PCB’s and PBB’s• Fungicide for citrus fruits• Major component of Heat Transfer
Fluids
Production HistoryProduction History
• Designated for testing in 1982 because 700 million lbs/yr were being produced (Rand)
• US Producers as of 1994:– Chevron Corporation (Baytown, TX)
– Koch Chemical Company (Corpus Christi, TX)
– Monsanto Chemical Company (Anniston, AL)
– Sybron Chemicals Company (Wellford, SC)
• Designated for testing in 1982 because 700 million lbs/yr were being produced (Rand)
• US Producers as of 1994:– Chevron Corporation (Baytown, TX)
– Koch Chemical Company (Corpus Christi, TX)
– Monsanto Chemical Company (Anniston, AL)
– Sybron Chemicals Company (Wellford, SC)
Mode of Entry into Aquatic EnvironmentMode of Entry into Aquatic Environment• Wastewater effluents
– From textile mills that use it as a dye carrier
– From industrial processes
• Leaking heat exchangers• Volatilization and sorption are
important
• Wastewater effluents – From textile mills that use it as a dye
carrier– From industrial processes
• Leaking heat exchangers• Volatilization and sorption are
important
Chemical Reactivity and SpeciationChemical Reactivity and Speciation• Biphenyl tends to partition into the
sediment– Soil sorption coefficients:
• mean value of 4230• Indicates that biphenyl will be practically
immobile in sediment
– But even this effect is minimal, since the majority of biphenyl is volatilized.
• Biphenyl tends to partition into the sediment– Soil sorption coefficients:
• mean value of 4230• Indicates that biphenyl will be practically
immobile in sediment
– But even this effect is minimal, since the majority of biphenyl is volatilized.
Toxicity to Aquatic LifeToxicity to Aquatic Life
• Acute toxicity:– Values as low as 0.36 mg/L
(daphnids) and 1.3 mg/L (rainbow trout).
– LC50 (96h):• Bluegill (L. macrochirus) - 4.7 mg/L• Sheepshead minnow - 4.6 mg/L• Fathead minnow - 6 mg/L
• Acute toxicity:– Values as low as 0.36 mg/L
(daphnids) and 1.3 mg/L (rainbow trout).
– LC50 (96h):• Bluegill (L. macrochirus) - 4.7 mg/L• Sheepshead minnow - 4.6 mg/L• Fathead minnow - 6 mg/L
Toxicity to Aquatic LifeToxicity to Aquatic Life
• Chronic Toxicity:– Done in daphnids and rainbow trout– Daphnids: 275 mg/L
• NOEC: 0.17mg/L
– Trout: 230 mg/L– Indicative of Low Chronic Toxicity– Studies with bacteria indicate no
mutagenic potential
• Chronic Toxicity:– Done in daphnids and rainbow trout– Daphnids: 275 mg/L
• NOEC: 0.17mg/L
– Trout: 230 mg/L– Indicative of Low Chronic Toxicity– Studies with bacteria indicate no
mutagenic potential
Toxic Effects NotedToxic Effects Noted
• In the aquatic environment:– Inhibition of growth
• Noted only in algae (Chlorella)• Slight inhibition at 1 mg/L• Complete inhibition at 10 mg/L
– Inhibition of food intake• Observed in Mytilus edulis• EC50 observed after 40 min of 0.3 mg/L
• Molecular mode of Toxicity:– unknown
• In the aquatic environment:– Inhibition of growth
• Noted only in algae (Chlorella)• Slight inhibition at 1 mg/L• Complete inhibition at 10 mg/L
– Inhibition of food intake• Observed in Mytilus edulis• EC50 observed after 40 min of 0.3 mg/L
• Molecular mode of Toxicity:– unknown
Mode of EntryMode of Entry
• Biphenyl enters an organism through:– Diet (accumulates in plants)– Since it is lipid soluble, tends to
partition into adipocytes
• Biphenyl enters an organism through:– Diet (accumulates in plants)– Since it is lipid soluble, tends to
partition into adipocytes
Biochemical MetabolismBiochemical Metabolism
• Soil:– Biodegredation – S. cerevisiae, Streptomyces, Achromobacter,
Pseudomonas putida, Oscillatoria, gram negative bacteria.
– Oxidize via CytP450 to 2,3 dihydroxybiphenyl– Fungi metabolize biphenyl to 4-hydroxy- or 2-
hydroxy- biphenyl and 4,4’-dihydroxybiphenyl
• Biochemical Metabolism
• Soil:– Biodegredation – S. cerevisiae, Streptomyces, Achromobacter,
Pseudomonas putida, Oscillatoria, gram negative bacteria.
– Oxidize via CytP450 to 2,3 dihydroxybiphenyl– Fungi metabolize biphenyl to 4-hydroxy- or 2-
hydroxy- biphenyl and 4,4’-dihydroxybiphenyl
• Biochemical Metabolism
Biochemical MetabolismBiochemical Metabolism• Water:
– Microbial degradation• Aromatic hydroxylation to 2-, 3-, and 4-
dihydroxybiphenyl• Activated sludge (74% in 14d)• Anaerobic digester (100% in 7d)• Aerated Lagoon (100% in 8h)• Retention Pond (100% in 96h)• Domestic Wastewater (79% in 5d)• Industrial Wastewater (87% in 24h)
– Photolysis• Irradiation with 250 nm light underwent 50%
degradation in 40 hours.
• Water:– Microbial degradation
• Aromatic hydroxylation to 2-, 3-, and 4- dihydroxybiphenyl
• Activated sludge (74% in 14d)• Anaerobic digester (100% in 7d)• Aerated Lagoon (100% in 8h)• Retention Pond (100% in 96h)• Domestic Wastewater (79% in 5d)• Industrial Wastewater (87% in 24h)
– Photolysis• Irradiation with 250 nm light underwent 50%
degradation in 40 hours.
Biochemical MetabolismBiochemical Metabolism
• Biota:– Bioconcentration Factors:
• Rainbow Trout - 436 L/kg• Algae - 540 L/kg• Orfe - 282 L/kg
– Suggests a moderate potential for accumulation in aquatic organisms
– Kow indicates an affinity for lipids
• Biota:– Bioconcentration Factors:
• Rainbow Trout - 436 L/kg• Algae - 540 L/kg• Orfe - 282 L/kg
– Suggests a moderate potential for accumulation in aquatic organisms
– Kow indicates an affinity for lipids
Defense MechanismsDefense Mechanisms
• Phase I and II metabolism• Defense mechanisms are not well
developed for Biphenyl due to:– Low concentrations being present in
water and sediment
• Phase I and II metabolism• Defense mechanisms are not well
developed for Biphenyl due to:– Low concentrations being present in
water and sediment
ConclusionConclusion
• Biphenyl has a high acute toxicity but low chronic toxicity
• Tends to volatilize• Low affinity for water• Virtually immobile in sediment• Quickly metabolized
• Biphenyl has a high acute toxicity but low chronic toxicity
• Tends to volatilize• Low affinity for water• Virtually immobile in sediment• Quickly metabolized
ReferencesReferences
• Rand, G.M. Fundamentals of Aquatic Toxicology: Effects, Environmental Fate, and Risk Assessment. 2nd Edition. CRC Press, New York, NY, 1995.
• Concise International Chemical Assessment Document (CICAD)– www.inchem.org/documents/cicads/cicads/cicad06.htm
• International Program on Chemical Safety (IPCS)– www.inchem.org
• National Pollution Inventory, Australian Government.– www. Npi.gov.au/database/substance-info/profiles/14.html
• Rand, G.M. Fundamentals of Aquatic Toxicology: Effects, Environmental Fate, and Risk Assessment. 2nd Edition. CRC Press, New York, NY, 1995.
• Concise International Chemical Assessment Document (CICAD)– www.inchem.org/documents/cicads/cicads/cicad06.htm
• International Program on Chemical Safety (IPCS)– www.inchem.org
• National Pollution Inventory, Australian Government.– www. Npi.gov.au/database/substance-info/profiles/14.html
ReferencesReferences
• OSHA– www.osha.gov
• Hazardous Substances Data Bank (HSDB)– http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?HSDB
• US Environmental Protection Agency (EPA)– www.epa.gov
• TSCA Compliance Guide– www.tsca.info
• OSHA– www.osha.gov
• Hazardous Substances Data Bank (HSDB)– http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?HSDB
• US Environmental Protection Agency (EPA)– www.epa.gov
• TSCA Compliance Guide– www.tsca.info