Wipe Sample Procedures for PAHs
Source: WildLaw

Note: It is important to talk to technical experts, the laboratory and other bucket brigaders who have done a wipe sample to determine if it is appropriate in your situation.  Below is the methodology we used to look for polycyclic aromatic hydrocarbons (PAHs) in Ocala, FL around a charcoal factory.  This may be relevant to test for other types of contaminants as well.

1.    Contact laboratory
a.    What analytes you are looking for
b.    Get the basics on how to test for those – type of surface is important
c.    Ask clarifying questions about shipping method, lab days and hours of operation, etc.

2.    Determine area/location/object you want to “wipe” and if necessary prep (we picked an older car without paint chipping because we wanted a solid metal surface without the interference of other chemicals; we parked the car in an area where there wasn’t significant tree cover or other overhanging impediments because we knew that PAHs would be attached to the particles being emitted from the smoke stacks; we rinsed (did not use soap or any chemicals) the car off for our first one to get a sense of how much accumulation over a certain number of days (for subsequent samples we sampled the areas as is just to see over time what has remained; I’d do both if possible);  then we let the car sit for six days before we did the sample.

3.    A few days before you want to sample, call the laboratory again and order the wipe sample kit.  Make sure they include blue gloves, multiple (as many as you want to sample plus a few extra) vials of solution (in our case it was hexane) with gauze wipes in each, a bigger vial called the temperature blank, ice packs (not cold), a chain of custody form and a cooler.

4.    Once you receive the kit, double check that everything is there and that you understand the wipe procedure as discussed with the laboratory.  If not, call the lab for further discussion.  Cooler will come with items in it but not cold; it does not need to be refrigerated prior to the taking the sample (unless the lab tells you otherwise for your contaminants of concern).  Put the ice packs in a freezer.

5.    Pick a day and time where you have enough time to do the sample, get it right to UPS for overnight shipping to the laboratory.  Preference is to do it later in the day because the temperature of the sample upon arrival at the lab is critical, but make sure you don’t do it so late that you miss the last shipping time.

6.    Take the sample by having at least two people put on the gloves.  Uncork one vial at a time and remove the gauze.  Prior to uncorking/unscrewing the top of each vial, we found that it was easier to tip the vial so that the gauze was close to the top and easy to pull out.  Try not to spill the solution or at least not significant portions of it.  Using the gauze on all sides wipe the surface you are sampling.  If you have enough residue on the surface, use the gauze or a stainless steel spatula (be careful not to scratch the surface as you don’t want to pick up anything from the paint, etc) to push the residue into the vial.  Place the gauze back into the vial when you are finished.  Replace the cap and prepare for shipping.  We suggest you do as many vials as you want sampled and an extra one or two in case there are any problems.

7.    To ship make sure your vials are secure in either an egg carton-like case the lab sent or wrap them in bubble wrap.  Put these, the temperature vial and the ice pack into the cooler.  You will eventually put your custody form into the cooler so don’t seal the cooler.

8.    Complete your chain of custody form, noting which vials you want analyzed, the extras you send you can request that they be analyzed if there are any problems with the ones you identified being analyzed or held for possible later request of analysis.

9.    Take to UPS (or have them come to you), as soon as possible after the sample is completed: the custody form, the cooler with all materials, a zip loc bag and a credit card or account number.

10.    Complete the chain of custody and shipping label.  Put the proper copy of the chain of custody signed by you and the UPS agent, into the zip loc bag, in the cooler.  Tape the cooler and sign across the seal.  Ship overnight.

11.    Call lab next day to confirm receipt and ask when analysis will be completed.