2,3',4,5-Tetrachlorobiphenyl (PCB-44): Lab Handling & Safety Guide
2,3',4,5-Tetrachlorobiphenyl (PCB-44): Lab Handling & Safety Guide
2,3',4,5-Tetrachlorobiphenyl is a tetrachlorinated polychlorinated biphenyl congener (PCB-44) widely used as a certified reference standard in environmental monitoring, toxicological research, and analytical method development.
- IUPAC Name
- 2-chloro-1-(3',4',5'-trichlorophenyl)benzene / 1,2',3,5'-tetrachlorobiphenyl (systematic PCB-44 nomenclature)
- PCB Congener Number
- PCB-44
- Molecular Formula
- C₁₂H₆Cl₄
- Molecular Weight
- 291.99 g/mol
- CAS Number
- 41464-39-5
- Recommended Storage
- Store at 2–8 °C in a tightly sealed container, away from light and ignition sources
- Typical Application
- Environmental reference standard, GC/MS and HPLC calibration, ecotoxicology studies
Chemical Identity and Physical Properties
2,3',4,5-Tetrachlorobiphenyl, designated PCB-44 under the Ballschmiter–Zell congener numbering system, belongs to the polychlorinated biphenyl (PCB) family of persistent organic pollutants. Its molecular formula is C₁₂H₆Cl₄ with a molecular weight of approximately 291.99 g/mol (CAS 41464-39-5). The compound carries four chlorine substituents positioned at the 2, 3', 4, and 5 ring positions of the biphenyl scaffold, conferring moderate lipophilicity and environmental persistence characteristic of mid-range chlorinated PCB congeners.
PCB-44 is a solid or semi-solid at room temperature with low water solubility and elevated log Kow values typical of tetra-chlorinated biphenyls, leading to significant bioaccumulation potential in fatty tissues of aquatic and terrestrial organisms. These physicochemical attributes make it a relevant analyte in food safety, sediment, and tissue monitoring programs.
Recommended Storage and Stability
To preserve chemical integrity and ensure suitability as a reference standard, 2,3',4,5-Tetrachlorobiphenyl (PCB-44) should be stored at 2–8 °C in tightly sealed amber glass vials. Exposure to UV light, heat, and moisture can lead to degradation or inadvertent contamination and must be avoided. Stock solutions prepared in organic solvents such as isooctane, hexane, or acetone should be stored under inert atmosphere or refrigeration and used within validated holding times.
Always verify product purity and certificate of analysis (CoA) upon receipt. For long-term archiving, storage at −20 °C under dry, dark conditions is advisable. Avoid repeated freeze-thaw cycles, which can compromise solution homogeneity and concentration accuracy critical for calibration work.
Safe Handling and Regulatory Considerations
PCBs, including PCB-44, are classified as persistent organic pollutants (POPs) under the Stockholm Convention and are subject to strict regulatory controls in most jurisdictions. Laboratory workers must handle 2,3',4,5-Tetrachlorobiphenyl exclusively within a certified chemical fume hood, wearing appropriate personal protective equipment (PPE) including nitrile gloves, lab coat, and safety goggles. Skin and inhalation exposure should be minimized at all times.
Waste disposal must comply with applicable local, national, and international regulations governing halogenated organic waste. Incineration at a licensed high-temperature facility is the recommended disposal route. Researchers should consult the Safety Data Sheet (SDS) provided by Aladdin Scientific before use, and ensure all personnel handling the compound are adequately trained. Documentation of use, quantities, and disposal is strongly advised for regulatory compliance and laboratory audit readiness.
Analytical Applications and Method Guidance
As a certified reference standard, 2,3',4,5-Tetrachlorobiphenyl (PCB-44) is primarily employed in the calibration and validation of chromatographic methods for PCB analysis. Gas chromatography coupled with mass spectrometry (GC/MS) or electron capture detection (GC/ECD) represents the gold standard for quantitative determination of PCB congeners in environmental matrices including water, soil, sediment, and biological tissue.
Working calibration solutions should be freshly prepared from certified stock solutions and verified against traceable reference materials. Method performance parameters—including linearity range, limit of detection (LOD), limit of quantification (LOQ), and recovery—should be documented in accordance with applicable standard methods such as EPA Method 8082A or ISO 6468. Solvent blanks and matrix-matched calibrators should be run concurrently to detect carry-over or matrix suppression effects.
Quality Assurance and Product Specifications
Aladdin Scientific supplies 2,3',4,5-Tetrachlorobiphenyl (SKU: T1539817) as a high-purity research reagent suitable for use as a reference standard in analytical and environmental chemistry applications. Each lot is accompanied by a Certificate of Analysis (CoA) detailing purity, batch number, and recommended storage conditions. Users should verify that the CoA purity meets the requirements of their specific analytical method prior to use.
For procurement, researchers should confirm solvent form (neat or dissolved), concentration (if supplied as solution), container size, and any applicable export or import regulations for controlled substances in their jurisdiction. Contact Aladdin Scientific technical support for custom formulation needs or additional documentation requirements such as ISO 17034-compliant reference material certification.
Frequently asked questions
What is the PCB congener number for 2,3',4,5-Tetrachlorobiphenyl?
2,3',4,5-Tetrachlorobiphenyl is designated PCB-44 under the Ballschmiter–Zell congener numbering system, which is the internationally recognized classification scheme for polychlorinated biphenyl congeners.
Which solvents are suitable for preparing stock solutions of PCB-44 for GC analysis?
Isooctane, n-hexane, and acetone are commonly used solvents for preparing PCB-44 stock solutions for GC/MS or GC/ECD analysis. Solvent selection should match the requirements of the specific standard method being employed, and solutions should be stored under refrigeration in sealed amber glass vials.
How should PCB-44 waste be disposed of in the laboratory?
PCB-44 waste must be managed as halogenated organic hazardous waste in accordance with local, national, and international regulations. Disposal via a licensed high-temperature incineration facility is the recommended approach. Under no circumstances should PCB-containing waste be poured down the drain or disposed of in general laboratory waste streams.
Is 2,3',4,5-Tetrachlorobiphenyl (PCB-44) subject to regulatory restrictions?
Yes. PCBs, including PCB-44, are regulated as persistent organic pollutants under the Stockholm Convention and are subject to strict controls in most countries. Researchers must comply with applicable national regulations regarding purchase, use, storage, and disposal, and may require specific permits depending on jurisdiction.
What purity grade is available for T1539817 from Aladdin Scientific?
Specific purity details for SKU T1539817 are provided in the Certificate of Analysis (CoA) accompanying each lot. Customers are advised to request or download the CoA from Aladdin Scientific to confirm purity meets the requirements of their intended application.
References
- Ballschmiter K, Zell M. Analysis of polychlorinated biphenyls (PCB) by glass capillary gas chromatography. Fresenius Z Anal Chem. 1980;302:20–31.
- United States Environmental Protection Agency. Method 8082A: Polychlorinated Biphenyls (PCBs) by Gas Chromatography. EPA SW-846. 2007.
- Stockholm Convention on Persistent Organic Pollutants. United Nations Environment Programme. 2001.
- ISO 6468:1996. Water quality — Determination of certain organochlorine insecticides, polychlorinated biphenyls and chlorobenzenes — Gas chromatographic method after liquid-liquid extraction.
Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.
危险品化学品经营许可证（带存储）