Particulate matter testing methods

U.S. EPA Test method 5 has several variations to measure total particulate matter including methods 5B, 5C, 5D, and 5F. 

U. S. EPA Regulations on Standards ofPeformanceforNeir Stationay Sources, 40 CER 60, Appendix A, Reference Methods, Washington, D.C., 1993. ASTM D3685-92, Standard Test Methodfor Sampling and Determination of Particulate Matter in Stack Gases, American Society for Testing Materials, Philadelphia, Pa., 1992. 

The instrumental analyzer procedure, EPA Method 3A, is commonly used for the determination of oxygen and carbon dioxide concentrations in emissions from stationary sources. An integrated continuous gas sample is extracted from the test location and a portion of the sample is conveyed to one or more instrumental analyzers for determination of O9 and CO9 gas concentrations (see Fig. 25-30). The sample gas is conditioned prior to introduction to the gas analyzer by removing particulate matter and moisture. Sampling is conducted at a constant rate for the entire test run. Performance specifications and test procedures are provided in the method to ensure reliable data. 

Particulate matter is defined in the USP as extraneous, mobile, undissolved substances, other than gas bubbles, unintentionally present in parenteral solutions. Test methods and limits for particulates are stated in the USP for large-volume injections and small-volume injections. 

Agut et al. (2011) assessed the different technology transfer options and reported that within Sanofi-Aventis that option 1 (comparative testing) is the approach of choice for critical methodologies, i.e. assay, degradation products, and in some cases water content and dissolution. Option 2 (co-validation) is reserved for less-critical methodologies, i.e. residual solvents by gas chromatography (GC), water content, dissolution and particle size methods whereas, option 4 (transfer waiver) is restricted to pharmacopoeial compendial methods, i.e. appearance, pH, particulate matter, etc. 

OTM-28 has been listed as conditional test methods for condensable particulate matter. 

It has to be said, there are a remarkable mix of topics in this section, ranging through a complete discussion of biotechnology-derived articles (<1045> and <1047>), cell and gene therapy products (<1046>), and validation of compendial (test) methods (<1225>). Specific methods for detection and measurement of suspended particulate matter are discussed in <788>, and there are detailed instructions on how to measure weights, <41>, volume <31>, or temperature <21>. Every student and, indeed, their supervisors need to be aware of what is in this valuable section there is so much valuable information that the compilers cannot be praised enough. 

Be fore using parametric methods, the data have to be transformed and tested to see if normal distribution occurs. Sometimes multimodal distributions exist, as illustrated in Fig. 1-8 for the occurrence of particulate matter in the atmosphere. A further difficulty in this case is that the type of distribution may change during the transmission process in the air. If normal... 

The list below is a summary of test methods that are most likely to be required during the testing of most common dosage forms (tablets, capsules, and solutions). The list is by no means an exhaustive (since test methods to determine moisture content, pH, sterility, particulate matter, and microbial testing are not listed) and the selection of test methods depends on an evaluation of a dosage form and also on the phase of drug development. For each type of test, most common techniques utilized are listed in square brackets. As can be seen, HPLC can be employed for aU of the following test methods. 

This type of counting device is designated in ASTM 3365-74T as a Tentative method of test for concentration and size distribution of airborne particulates collected in liquid media . It is specified that the method is suitable for particulate matter greater than 0.6 pm in diameter collected by a Greenburg-Smith or midget impinger. The original development of the method was carried out by Anderson et. al. [7] and was extended by others. 

Kristensen, P. 1991. Bioconcentration in fish Comparison of BCFs derived from OECD and ASTM testing methods influence of particulate matter to the bioavailability of chemicals. Danish Water Quality Institute... 

All parenterally injected solutions should be checked for particulate contamination but the above procedure is clearly impractical as a bulk screening exercise. Those products contaminated with particulate matter should be rejected. In practice, all products may be tested individually by humans against split white/black screens and/or under polarized light for obvious particulate contamination and again there is a method described in pharmacopoeias based on the split screen technique. Nowadays optical control equipment can take over this arduous and boring employment. 

Therefore, admixture studies are performed on parenteral drugs with commonly used intravenous diluents. Studies are performed by preparing admixtures of the drug product with various diluents in an appropriate type of flexible intravenous bag. Initial samples are taken for analysis before the bags are stored in temperature-controlled stability chambers. Subsequent samples may be pulled at 6-, 12-, 24-, 48-, and 72-h time points. The analytical tests commonly performed include visual appearance, pH, and HPLC assay. Degradation products are not commonly tested unless the method has been previously evaluated for specificity and stability-indicating ability with a particular intravenous diluent. This is necessary because there may be differences in the stability profile of the product in its original formulation compared to the admixture solution. Formation of any particulate matter is detected by visual... 

The USP includes different tests for the detection, sizing, and enumeration of subvisual particles, e.g., 10 and 25 pm. There are two test approaches for particulate matter recognized by the USP. They are automated liquid particle counting either by the light obscuration method or the light (laser) scattering method used mainly for SVPs, and the microscopic method used predominantly for LVPs. 

Kerosene, because of its higher density and viscosity, tends to retain fine particulate matter and water droplets in suspension for a much longer time than gasoline. Free water in kerosene can be detected by the use of a Dean and Stark adaptor (ASTM D-4006, IP 358) (Fig. 7.3), by the Karl Fischer titration method (ASTM D-1744, ASTM D-6304), by the distillation method (ASTM D-95, IP 74), or by a series of alternate tests (ASTM D-4176, ASTM D-4860). The standard water reaction test method (ASTM D-1094, IP 289) can also be used. 

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