Environmental Protection Agency (EPA)
EPA Method 5035: Closed-System Purge-And-Trap And Extraction For Volatile Organics In Soil And Waste Samples
1. Scope & Application
- This method details a closed-system purge-and-trap technique for analyzing volatile organic compounds (VOCs) in solid materials such as soils, sediments, and solid waste. While primarily for low VOC levels, it also covers procedures for high concentration samples and oily wastes. Sample collection and preparation align with the outlined procedures, and sample introduction uses the aqueous purge-and-trap procedure in Method 5030. These methods are compatible with various gas chromatographic procedures, including but not limited to Methods 8015, 8021, and 8260.
- The low soil method employs a hermetically sealed sample vial that remains sealed from sampling to analysis. ILT’s SURE Clean cap includes a protective built-in overlay cap that ensures sample cleanliness protection from collection point to analytical testing in the laboratory. This prevents VOC losses during sample transport and analysis. The method’s applicable concentration range (0.5 to 200 µg/kg) depends on the determinative method, matrix, and compound.
- Method 5035 is suitable for volatile organic compounds with boiling points below 200°C and low water solubility. It can include volatile, water-soluble compounds, but their quantitation limits (by GC or GC/MS) are approximately ten times higher due to lower purging efficiency.
- Method 5035, coupled with Method 8015 (GC/FID), is suitable for analyzing the aliphatic hydrocarbon fraction in the light ends of total petroleum hydrocarbons like gasoline. For the aromatic fraction (BTEX), employ Method 5035 in conjunction with Method 8021 (GC/PID). A comprehensive analysis of gasoline fractions is achievable by utilizing Method 8021 in series with Method 8015.
- When employing any preparative method for volatiles, it’s essential to screen samples to prevent contamination of the purge-and-trap system by materials with concentrations beyond the low concentration method’s calibration range. Since the sealed sample container can’t be opened without compromising integrity, it’s advisable to collect multiple sample aliquots for screening and potential reanalysis.
- This method is limited to trained analysts or those under supervision. Analysts must demonstrate proficiency in producing acceptable results using this method.
2. Summary of Method
- The first option is to collect a bulk sample without a preservative solution. In the laboratory, a portion of the sample is dispersed in a water-miscible solvent to dissolve volatile organic constituents. This solution, along with surrogates and internal standards, if applicable, is purged using Method 5030 and analyzed by a suitable determinative method. However, this procedure involves opening the vial and removing soil, which may result in the loss of some volatile constituents during handling.
- The second option involves collecting an approximately 5-g sample in a pre-weighed vial with a septum-sealed screw-cap containing 5 mL of water-miscible organic solvent (e.g., methanol). ILT offers a variety of screw caps with bonded septum liners that provide protection of the sample in transit and clean analytical testing. During analysis, surrogates are added to the vial, and an aliquot of the solvent is purged using Method 5030 and analyzed by an appropriate determinative method.
- The high concentration oily waste method is generally suitable for oily samples with VOC concentrations exceeding 200 µg/kg that can be diluted in a water-miscible solvent.
- Samples with oils or significant oil content pose additional analytical challenges. This procedure is generally suitable for such samples when they are soluble in a water-miscible solvent.
3. Interferences
- Contamination issues primarily arise from impurities in the purge gas and organic compounds out-gassing from the plumbing before the trap. To ensure contamination-free conditions, the analytical system should undergo testing with method blanks. Avoid the use of non-PTFE plastic coating, non-PTFE thread sealants, or flow controllers with rubber components in the purging device, as they out-gas organic compounds concentrated in the trap during purging. All ILT caps provide a silicone/PTFE surface barrier on the septum material. Such compounds can lead to interferences or false positives in the determinative step.
- The lab for volatile analysis must be solvent-free, with specific attention to methylene chloride. The analytical and sample storage area should be isolated from atmospheric methylene chloride sources to avoid random background levels. Precautions are necessary if other organic solvents are present in the lab, as they can also cause random background levels.
4. Apparatus & Materials
- The necessary sample containers depend on the chosen purge-and-trap system. Some systems have specific requirements, while others allow the use of any quality glass vial large enough to hold at least 5 g of soil, 10 mL of water, and sealable with a screw-cap containing a PTFE-faced silicone septum. Refer to the purge-and-trap system manufacturer’s instructions for guidance on suitable vials, septa, caps, and mechanical agitation devices.
5. Quality Control
- Each lab must show proficiency with each sample preparation and determinative method it uses, producing accurate and precise data for target analytes in a clean matrix.
- The laboratory is advised to implement additional quality assurance practices with this method, tailored to the laboratory’s needs and sample characteristics. It is recommended to analyze standard reference materials and participate in relevant performance evaluation studies whenever possible.
Food and Drug Administration (FDA)
According to the FDA, any packaging that directly interacts with food is classified as a “food contact substance.” The Office of Food Additive Safety and The Center for Food Safety and Applied Nutrition (CFSAN) bear the responsibility of ensuring the safety of such substances, which include: plastics, paper, coatings, food coloring, and adhesives.
In addition to overseeing food packaging, the FDA plays a crucial role in regulating pharmaceutical and cosmetic packaging, significantly influencing consumer safety and public health. The FDA’s stringent regulations in the pharmaceutical industry ensure that packaging meets high standards for preserving the integrity and safety of medications. In clinical diagnostics, FDA guidelines contribute to the reliability and accuracy of diagnostic tools and their packaging. Similarly, in the cosmetic industry, the FDA ensures that packaging materials meet safety standards, safeguarding consumers from potential health risks. This comprehensive regulatory approach underscores the FDA’s commitment to upholding the highest standards across diverse industries, promoting the safety and well-being of the public.
FDA Guidance on Container Closure Systems for Packaging Human Drugs and Biologics
- The Federal Food, Drug, and Cosmetic Act (the Act) requires thorough information about packaging materials. According to Section 501(a)(3) of the Act, a drug is considered adulterated if its container contains any harmful substance that may jeopardize health. Additionally, Section 502 specifies that a drug is labeled as misbranded if there are packaging omissions. Furthermore, Section 505 mandates a comprehensive description of the methods, facilities, and controls employed in drug packaging.
FDA Regulations on Pharmaceutical Packaging
- Ensure medication quality by guarding against exposure to light, moisture, oxygen, and temperature variations. Containers must maintain airtight integrity, even with repeated opening and closing.
- Prevent physical damage during handling, shipping, and storage processes.
- Safeguard against biological contamination, ensuring the container and materials have no adverse interaction with the medication. Packaging must prevent leaks, diffusion, and permeation without altering the medication’s properties or effectiveness. Rigorous quality assurance is imperative for materials used in pharmaceutical packaging.
- Clearly label packages with product details, patient information, dispenser’s name and address, prescribing doctor’s details, recommended dosage, medication strength, quantity, cautionary warnings, storage instructions, and expiration date.
State of California Regulations
California currently mandates the lowest contaminant levels for water testing, which other states have subsequently adopted as their norm. ILT tests all caps to ensure that they meet the low level requirements for all 24mm Environmental caps. See all ILT products here.
California Safe Drinking Water Laws
By July 1, 2020, the state board must define microplastics in drinking water. Additionally, by July 1, 2021, the state board is required to:
- Establish a standardized methodology for testing microplastics in drinking water.
- Set forth requirements for a four-year testing and reporting program on microplastics in drinking water, with public disclosure of results.
- Consider issuing a notification level or guidance to assist consumers in interpreting the testing outcomes.
- Accredit California-based laboratories qualified to analyze microplastics.
Starting January 1, 2023, California will ban the sale of food packaging with regulated PFAS chemicals. The law also mandates cookware manufacturers to disclose intentionally added PFAS chemicals on their websites by January 1, 2023, and on product labels by January 1, 2024.
California Law on PFAS in Recyclables
A product or packaging shall not be considered recyclable in the state unless the product or packaging meets all of the following criteria, as applicable:
The product or packaging is not made from plastic or fiber that contains perfluoroalkyl or polyfluoroalkyl substances or PFAS that meets either of the following criteria:
- PFAS that a manufacturer has intentionally added to a product or packaging and that have a functional or technical effect in the product or packaging, including the PFAS components of intentionally added chemicals and PFAS that are intentional breakdown products of an added chemical that also have a functional or technical effect in the product.
- The presence of PFAS in a product or product component or packaging or packaging component at or above 100 parts per million, as measured in total organic fluorine.
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