... /The authors/ have investigated the biotransformation of dibenz(a,h)acridine (DB(a,h)ACR), an aza-PAH with two nonidentical bay regions, by recombinant human cytochromes P450 1A1, 1B1, and 3A4 and rat P450 1A1. Among the three P450s, 1A1 was the most effective in metabolizing DB(a,h)ACR followed by 1B1 and 3A4. The major DB(a,h)ACR metabolites produced by human P450 1A1 and 1B1 were the dihydrodiols with a bay region double bond, namely, DB(a,h)ACR-3,4-diol and DB(a,h)ACR-10,11-diol (putative proximate carcinogen). P450 1A1 produced a higher proportion of DB(a,h)ACR-10,11-diol (derived from the benzo ring adjacent to the nitrogen) (44.7%) than of DB(a,h)ACR-3,4-diol (derived from benzo ring away from the nitrogen) (23.8%). In contrast, 1B1 produced a much greater proportion of 3,4-diol (54.7%) than of 10,11-diol (6.4%). These data indicate that (i) human P450 1A1 and 1B1 differ dramatically with respect to the regiospecific metabolism of DB(a,h)ACR, (ii) human P450 1A1 is substantially more active than human P450 1B1 in the metabolic activation of the aza-PAH to its 10,11-diol, and (iii) the presence of nitrogen influences the relative extent to which the two benzo ring diols with a bay region double bond are formed by human P450s 1A1 and 1B1. In contrast to human P450s 1A1 and 1B1, rat P450 1A1 showed no regioselectivity in the metabolism of DB(a,h)ACR producing nearly equal proportions of 10,11-diol and 3,4-diol. Despite significant differences in their regioselectivity, human P450 1A1 and 1B1 and rat P450 1A1 showed similar stereoselectivity in the metabolism of DB(a,h)ACR to its diols having a bay region double bond, producing primarily the R,R enantiomers (>94%). The data of these studies indicate that human and rat P450 1A1 differ in their regioselectivity in the metabolism of DB(a,h)ACR to its two benzo ring diols with a bay region double bond and consequently in their ability to metabolically activate the parent aza-PAH. However, human and rat P450 1A1 do not differ with respect to their stereoselectivity in the metabolism of DB(a,h)ACR to the diols.
The carcinogen dibenz(a,h)acridine (DB(a,h)ACR is metabolized predominantly to trans-3,4-dihydroxy-3,4-dihydro-dibenz(a,h)acridine (DB(a,h)ACR-3,4-diol) and the proximate carcinogen trans-10,11-dihydroxy-10,11-dihydrodibenz(a,h)acridine (DB(a,h)ACR-10,11-diol). In the present investigation, the stereoselectivity of rat liver enzymes in metabolism of DB(a,h)ACR to its 3,4-diol and 10,11-diol and of DB(a,h)ACR-10,11-diol enantiomers to their bay-region diol epoxides has been examined with liver microsomes from control and 3-methylcholanthrene-treated rats. Both microsomal preparations produced the major metabolites DB(a,h)ACR-3,4-diol and DB(a,h)ACR-10,11-diol containing predominantly R,R-enantiomers with 38-54% optical purity. Metabolism of (-)-(10R,11R)- and (+)-(10S,11S)-enantiomers of DB(a,h)ACR-10,11-diol by liver microsomes from control rats produced predominantly bay-region diol epoxides (46-59% of total metabolites), whereas very little bay-region diol epoxides (14-17% of total metabolites) were produced by liver microsomes from 3-methylcholanthrene-treated rats. The bay-region diol epoxides produced in these studies consisted of predominantly DB(a,h)ACR-10,11-trans-diol epoxide diastereomer in which the benzylic hydroxyl group and epoxide oxygen are trans. However, (-)-DB(a,h)ACR-10R,11R-diol, a major metabolite of DB(a,h)ACR, was metabolized by liver microsomes from 3-methylcholanthrene-treated rats to (+)-(8R,9S,10S,11R)-DB(a,h)ACR-10,11-trans-diol epoxide ... in an amount which was 6.5-fold greater than that of the corresponding cis-diol epoxide diastereomer. The relative amounts of trans-diol epoxide versus cis-diol epoxide in the mixture of bay-region diol epoxides produced from DB(a,h)ACR-10R,11R-diol and DB(a,h)ACR-10S,11R-diol with liver microsomes from control rats and from DB(a,h)ACR-10S,11S-diol with liver microsomes from 3-methylcholanthrene-treated rats were 1.7, 2.1 and 2.3 respectively.
As part of a project to assess the effect of heterocyclic nitrogen in modifying the metabolism and mutagenicity of polycyclic aromatic hydrocarbons, /the authors/ investigated the metabolism of dibenz(a,h)acridine (DB(a,h)AC) by liver microsomes prepared from male Sprague-Dawley rats. During a 6-min incubation 21, 14, 0.7 or 0.2 nmol DB(a,h)AC per mg protein were metabolized by microsomes from rats pre-treated with DB(a,h)AC, 3-methylcholanthrene (3-MC), phenobarbital (PB) or corn oil, respectively. In each case the predominant metabolites were the dihydrodiols with bay-region double bonds, namely, DB(a,h)AC-3,4-dihydrodiol and DB(a,h)AC-10,11-dihydrodiol, each of which accounted for 21-23% of the total metabolism determined during a 7-min incubation with microsomes from 3-MC-treated rats. Other metabolites produced by these microsomes included DB(a,h)AC-1,2-dihydrodiol (approximately 5% of total metabolites); two K-region oxides (DB(a,h)AC-12,13- and 5,6-oxides (estimated to represent 5% and 2% of total metabolites, respectively)); several unidentified polar metabolites (10-15%) and several unidentified metabolites which co-eluted with 3-hydroxy-DB(a,h)AC (20%). DB(a,h)AC-8,9-dihydrodiol was not detected (less than 2%). The metabolite profiles produced by microsomes prepared from rats pretreated with DB(a,h)AC, PB or corn oil were very similar to the profile produced by 3-MC-induced microsomes. /Investigators/ conclude that: the potentially mutagenic benzo-ring dihydrodiols with bay-region double bonds are the predominant metabolite of DB(a,h)AC; the heterocyclic nitrogen atom has little effect in modifying the relative extents of formation of these two benzo-ring dihydrodiols with bay-region double bonds; metabolism at the K-region is only a minor pathway for DB(a,h)AC, as is also true for the carbon analogue dibenz(a,h)anthracene; and induction by a 3-MC-type inducer (e.g. DB(a,h)AC) is required for substantial metabolism to occur.
No data are available in humans. Sufficient evidence of carcinogenicity in animals. OVERALL EVALUATION: Group 2B: The agent is possibly carcinogenic to humans.
来源:Hazardous Substances Data Bank (HSDB)
毒理性
致癌性证据
二苯并(a,h)芘：合理预期为人类致癌物。/多环芳烃/
Dibenz(a,h)acridine: reasonably anticipated to be a human carcinogen. /Polycyclic Aromatic Hydrocarbons/
来源:Hazardous Substances Data Bank (HSDB)
毒理性
致癌物分类
国际癌症研究机构致癌物：二苯并[a,h]芘
IARC Carcinogenic Agent:Dibenz[a,h]acridine
来源:International Agency for Research on Cancer (IARC)
毒理性
致癌物分类
国际癌症研究机构（IARC）致癌物分类：2B组：可能对人类致癌
IARC Carcinogenic Classes:Group 2B: Possibly carcinogenic to humans
来源:International Agency for Research on Cancer (IARC)
IARC Monographs:Volume 32: (1983) Polynuclear Aromatic Compounds, Part 1: Chemical, Environmental and Experimental Data
Volume Sup 7: Overall Evaluations of Carcinogenicity: An Updating of IARC Monographs Volumes 1 to 42, 1987; 440 pages; ISBN 92-832-1411-0 (out of print)
Volume 103: (2013) Bitumens and Bitumen Emissions, and some N- and S-Heterocyclic Aromatic Hydrocarbons
来源:International Agency for Research on Cancer (IARC)
Section 1. IDENTIFICATION OF THE SUBSTANCE/MIXTURE Product identifiers Product name : Dibenz(a,h)acridine CAS-No. : 226-36-8 Relevant identified uses of the substance or mixture and uses advised against Identified uses : Laboratory chemicals, Manufacture of substances Section 2. HAZARDS IDENTIFICATION Classification of the substance or mixture Classification according to Regulation (EC) No 1272/2008 [EU-GHS/CLP] Acute toxicity, Oral (Category 3) Serious eye damage (Category 1) Carcinogenicity (Category 2) Classification according to EU Directives 67/548/EEC or 1999/45/EC Limited evidence of a carcinogenic effect. Harmful if swallowed. Risk of serious damage to eyes. Label elements Labelling according Regulation (EC) No 1272/2008 [CLP] Pictogram Signal word Danger Hazard statement(s) H301 Toxic if swallowed. H318 Causes serious eye damage. H351 Suspected of causing cancer. Precautionary statement(s) P280 Wear protective gloves/ eye protection/ face protection. P301 + P310 IF SWALLOWED: Immediately call a POISON CENTER or doctor/ physician. P305 + P351 + P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. Supplemental Hazard none Statements According to European Directive 67/548/EEC as amended. Hazard symbol(s) R-phrase(s) R40 Limited evidence of a carcinogenic effect. R22 Harmful if swallowed. R41 Risk of serious damage to eyes. S-phrase(s) S26 In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S39 Wear eye/face protection. Other hazards - none Section 3. COMPOSITION/INFORMATION ON INGREDIENTS Substances Molecular Weight : 279,35 g/mol Component Concentration Dibenz[a,h]acridine CAS-No. 226-36-8 - Section 4. FIRST AID MEASURES Description of first aid measures General advice Consult a physician. Show this safety data sheet to the doctor in attendance. If inhaled If breathed in, move person into fresh air. If not breathing, give artificial respiration. Consult a physician. In case of skin contact Wash off with soap and plenty of water. Take victim immediately to hospital. Consult a physician. In case of eye contact Rinse thoroughly with plenty of water for at least 15 minutes and consult a physician. If swallowed Never give anything by mouth to an unconscious person. Rinse mouth with water. Consult a physician. Most important symptoms and effects, both acute and delayed To the best of our knowledge, the chemical, physical, and toxicological properties have not been thoroughly investigated. Indication of any immediate medical attention and special treatment needed no data available Section 5. FIREFIGHTING MEASURES Extinguishing media Suitable extinguishing media Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide. Special hazards arising from the substance or mixture no data available Advice for firefighters Wear self contained breathing apparatus for fire fighting if necessary. Further information no data available Section 6. ACCIDENTAL RELEASE MEASURES Personal precautions, protective equipment and emergency procedures Wear respiratory protection. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas. Avoid breathing dust. Environmental precautions Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided. Methods and materials for containment and cleaning up Pick up and arrange disposal without creating dust. Sweep up and shovel. Keep in suitable, closed containers for disposal. Reference to other sections For disposal see section 13. Section 7. HANDLING AND STORAGE Precautions for safe handling Avoid contact with skin and eyes. Avoid formation of dust and aerosols. Provide appropriate exhaust ventilation at places where dust is formed. Conditions for safe storage, including any incompatibilities Store in cool place. Keep container tightly closed in a dry and well-ventilated place. Specific end use(s) no data available Section 8. EXPOSURE CONTROLS/PERSONAL PROTECTION Control parameters Components with workplace control parameters Exposure controls Appropriate engineering controls Avoid contact with skin, eyes and clothing. Wash hands before breaks and immediately after handling the product. Personal protective equipment Eye/face protection Face shield and safety glasses Use equipment for eye protection tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU). Skin protection Handle with gloves. Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands. The selected protective gloves have to satisfy the specifications of EU Directive 89/686/EEC and the standard EN 374 derived from it. Body Protection Complete suit protecting against chemicals, The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace. Respiratory protection Where risk assessment shows air-purifying respirators are appropriate use a full-face particle respirator type N100 (US) or type P3 (EN 143) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU). Section 9. PHYSICAL AND CHEMICAL PROPERTIES Information on basic physical and chemical properties a) Appearance Form: solid b) Odour no data available c) Odour Threshold no data available d) pH no data available e) Melting point/freezing 226 °C point f) Initial boiling point and no data available boiling range g) Flash point no data available h) Evaporation rate no data available i) Flammability (solid, gas) no data available j) Upper/lower no data available flammability or explosive limits k) Vapour pressure no data available l) Vapour density no data available m) Relative density no data available n) Water solubility no data available o) Partition coefficient: n- log Pow: 5,735 octanol/water p) Auto-ignition no data available temperature q) Decomposition no data available temperature r) Viscosity no data available s) Explosive properties no data available t) Oxidizing properties no data available Other safety information Solubility in other Ethanol Benzene Acetone solvents Section 10. STABILITY AND REACTIVITY Reactivity no data available Chemical stability no data available Possibility of hazardous reactions no data available Conditions to avoid no data available Incompatible materials Strong oxidizing agents Hazardous decomposition products Other decomposition products - no data available Section 11. TOXICOLOGICAL INFORMATION Information on toxicological effects Acute toxicity no data available Skin corrosion/irritation no data available Serious eye damage/eye irritation no data available Respiratory or skin sensitization no data available Germ cell mutagenicity Genotoxicity in vivo - rat - Intratracheal Genotoxicity in vivo - rat - Intratracheal Sister chromatid exchange Genotoxicity in vivo - rat - Intratracheal Micronucleus test Genotoxicity in vivo - rat Morphological transformation. Genotoxicity in vivo - mouse Morphological transformation. Carcinogenicity Limited evidence of a carcinogenic effect. IARC: 2B - Group 2B: Possibly carcinogenic to humans (Dibenz[a,h]acridine) Reproductive toxicity no data available Specific target organ toxicity - single exposure no data available Specific target organ toxicity - repeated exposure no data available Aspiration hazard no data available Potential health effects Inhalation May be harmful if inhaled. May cause respiratory tract irritation. Ingestion Toxic if swallowed. Skin May be harmful if absorbed through skin. May cause skin irritation. Eyes Causes eye burns. Signs and Symptoms of Exposure To the best of our knowledge, the chemical, physical, and toxicological properties have not been thoroughly investigated. Additional Information RTECS: Not available Section 12. ECOLOGICAL INFORMATION Toxicity no data available Persistence and degradability no data available Bioaccumulative potential no data available Mobility in soil no data available Results of PBT and vPvB assessment no data available Other adverse effects Section 13. DISPOSAL CONSIDERATIONS Waste treatment methods Product Offer surplus and non-recyclable solutions to a licensed disposal company. Dissolve or mix the material with a combustible solvent and burn in a chemical incinerator equipped with an afterburner and scrubber. Contaminated packaging Dispose of as unused product. Section 14. TRANSPORT INFORMATION UN number ADR/RID: 3077 IMDG: 3077 IATA: 3077 UN proper shipping name ADR/RID: ENVIRONMENTALLY HAZARDOUS SUBSTANCE, SOLID, N.O.S. (Dibenz[a,h]acridine) IMDG: ENVIRONMENTALLY HAZARDOUS SUBSTANCE, SOLID, N.O.S. (Dibenz[a,h]acridine) IATA: Environmentally hazardous substance, solid, n.o.s. (Dibenz[a,h]acridine) Transport hazard class(es) ADR/RID: 9 IMDG: 9 IATA: 9 Packaging group ADR/RID: III IMDG: III IATA: III Environmental hazards ADR/RID: yes IMDG Marine Pollutant: yes IATA: yes Special precautions for user Further information EHS-Mark required (ADR 2.2.9.1.10, IMDG code 2.10.3) for single packagings and combination packagings containing inner packagings with Dangerous Goods > 5L for liquids or > 5kg for solids. SECTION 15 - REGULATORY INFORMATION N/A
A compound represented by the following formula (1):
一个由以下化学式（1）表示的化合物：
Smoke filters for smoking devices with porous masses having a carbon particle loading and an encapsulated pressure drop
申请人：Celanese Acetate LLC
公开号：EP2636319A2
公开（公告）日：2013-09-11
Disclosed are filters, smoking devices, related articles and apparatus, and related methods. The filters (14) include porous masses (18) that have an active particle and a binder particle, wherein the active particle comprises carbon and the porous mass has a carbon loading of at least about 6 mg/mm and an encapsulated pressure drop of about 20 mm of water or less per mm of porous mass.
Method for obtaining a carbon black powder by pyrolyzing scrap rubber, the carbon black thus obtained and the use thereof
申请人：BLACK BEAR CARBON B.V.
公开号：US10119031B2
公开（公告）日：2018-11-06
The present invention relates to a method for recycling scrap rubber comprising the steps of pyrolyzing scrap rubber to obtain a char material and milling the thus obtained char material. The present invention also relates to carbon black powders and carbon black pellets obtained by the method according to the invention. Moreover, the present invention relates to the use of said carbon black powder and to compositions comprising said carbon black powders.
Products of high denier per filament and low total denier tow bands
申请人：Celanese Acetate LLC
公开号：US10299509B2
公开（公告）日：2019-05-28
A method for forming a filter rod may include providing a bale of crimped tow band having about 10 denier per filament or greater and about 20,000 total denier or less, the crimped tow band comprising a plurality of cellulose acetate filaments; and placing the crimped tow band in an apparatus so as to form a filter rod.
