Wipe sampling

Wipe sampling involves swiping a dry or wet (use of a solvent or other liquid besides water in eommonplaee) eloth, glass fiber filter paper, or swab over the surfaee of a potentially eontaminated objeet and performing a laboratory analysis. Both the inner and outer surfaees of PPE should be tested to eheek for permeation. Skin ean also be tested using this wipe sampling [1]. 

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Describe what wipe samples are and how they can be applied to an lAQ assessment. 

The audit team took wipe samples from the surfaee of the disearded PPE and analyzed them for metals, pestieides, and SVOCs, but found no deteetable eontamination. The Site I eontraetor, however, did not have additional sampling data from different days or varying eireumstanees to verify that on a eonsistent basis, eontamination was not being spread to elean areas of the site beeause of the laek of deeontamination operations. 

Other than wipe sampling of elean areas, the Site J eontraetor did not implement proeedures to evaluate the eflfeetiveness of personal deeontamination methods. Deeontaminated equipment was tested by wipe sampling. Further deeontamination was performed as neeessary until wipe samples fell below the eontraetor s trigger levels. 

Face wipe samples are treated similarly. The face wipe is placed in an appropriate jar and wet with the appropriate amount of wash solution. The sample is then spiked using a 1-mL volumetric pipet and immediately capped, processed, and frozen. 

A short weathering time for hand wash and face wipe samples is appropriate since these types of samples taken from test volunteers are usually processed and frozen immediately and are not subjected to weathering as are the dosimeter or air matrices. 

Outdoor lead dust was found to be a more potent contaminant of children s hands than indoor lead dust at day care centers in New Orleans boys, in general, had higher hand lead levels than girls. The conclusions were based on lead analysis of hand wipe samples taken before and after children played outdoors at four different day care centers (a private inner-city site, a private outer-city site, a public inner-city site, and a public outer-city site). The private inner-city site had a severely contaminated outdoor play area with measured soil lead concentrations ranging from 287 to 1,878 mg/kg. The outdoor play area at the public inner-city site, where children exhibited the lowest hand lead measurements of any site in the study, had been completely paved over with concrete or rubberized asphalt and had well-maintained equipment (Viverette et al. 1996). 

ASTM. 1998b. ASTM E 1644. Standard practice for hot plate digestion of dust wipe samples for the determination of lead by atomic spectrometry. American Society for Testing and Materials. 

ASTM. 1998f. ASTME 1728. Standard practice for field collection of settled dust samples using wipe sampling methods for lead determination by atomic spectrometry techniques. American Society for Testing and Materials. 

NIOSH. 1994. NIOSH Manual of Analytical Methods, 4th edition. Methods 7082 (Lead by Flame AAS), 7105 (Lead by HGAAS), 7505 (Lead Sulfide), 8003 (Lead in blood and urine), 9100 (Lead in Surface Wipe Samples), U.S. Department of Health and Human Services, Centers for Disease Control, National Institute for Occupational Safety and Health. 

The use of activation analysis in criminal investigations (forensic activation analysis) is also well established. The basic idea here is to match the trace-element distributions found in bullets, paint, oil, and so on found at the scene of a crime with the trace-element distributions in objects found with criminal suspects. Such identification is rapid and nondestructive (allowing the actual evidence to be presented in court). Moreover, the probability of its correctness can be ascertained quantitatively. Other prominent examples of the use of forensic activation analysis involve confirmation of the notion that Napoleon was poisoned (by finding significant amounts of arsenic in hair from his head) and the finding that the activation analysis of the wipe samples taken from a suspect s hand can reveal not only if he or she has fired a gun recently but also the type of gun and ammunition used. 

We use wipe sampling to detect contaminants on non-porous surfaces, such as the surfaces of plastic or metal drums transformer casings various heavy equipment walls floors ceilings laboratory benches. Sampling with wipes allows transferring contaminants from a surface area of a known size onto the wipe material. The wipes are then analyzed, and the amounts of contaminants found on the wipe are related to the surface area. 

Typically, we perform wipe sampling in the following situations ... 

In wipe sampling, the same area cannot be sampled twice. To sample the same sampling point for a different class of contaminants, we delineate an adjoining area and wipe it with a chemical appropriate for the target analyte. To thoroughly cover the sampled area, the wiping motion inside the template is performed in two directions, horizontal and vertical, as shown in Figure 3.12. We place the used wipe into a preserved sample container and submit it to the laboratory for analysis. 

For large-scale operations, equipment and workplace should be verified, as applicable, as clean by wipe sampling, for GMP areas... 

Equipment and area should be verified as clean using wipe sampling techniques (when compound specific analytical methods are available)... 

Employee Exposure Monitoring. Industrial hygiene assessment of surface concentrations associated with a potent compound handled solely in liquid form within a chemical laboratory hood was conducted to assess the potential for downstream contamination potential. Handling operations assessed included dilutions of sample solutions and HPLC analysis. Wipe samples were collected from the following surfaces within and outside of the laboratory ... 

It is recommended that periodic surface wipe sampling is conducted to monitor surface contamination within and outside of the laboratory and to maintain employee and supervision attention to good working practices. 

An additional part of the sample collection kit are solvents (dichloromethane, methanol, water) and decontamination solutions. Solvents are necessary -in accordance with approved procedures - to collect wipe samples. These solvents need to be transported as dangerous goods, which require special transport arrangements. 

Separately packed wipes, stiff wires, alligator clips, clamps to take wipe samples... 

Samples may be of solid or liquid matrix or be a surface wipe sample from various sampling points as indicated below ... 

If no apparent liquid/solid samples are available wipe samples can be collected from various surfaces, for example,... 

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