- For Bulk Samples
To analyze for the allergen levels in bulk dust samples, we need 100mg of fine dust. Our recent findings (click link below) indicate that due to increased potential for variability, allergen analysis should not be attempted unless a minimum of 10mg fine dust is available. Samples with less than 10mg available of fine dust will not be analyzed and a “Not Enough Sample (NES)” charge will be applied.
“Variability introduced into allergen immunoassays during the dust extraction process”
- For DUSTREAM™ Samples
If using the DUSTREAM™ and sampling for the recommended area and time yields very little or no dust, continue sampling until the filter is 1/4 full. Our allergen results are not based on area, but on microgram of allergen per gram of dust.
- For Extracted Samples
For allergen extracts or extracts of bulk dust or air filters, we need a minimum of 0.5 mL, especially if testing for multiple allergens.
- For Air Filter Samples
For air sampling cassettes, the whole filter is extracted with 1ml of PBS extraction solution and the results are reported as ng or µg allergen per filter.
- For Bulk Samples
To analyze for endotoxin levels in bulk dust samples, we need 100mg of fine dust. Samples of bulk dust will not be processed if there is less than 20mg of fine dust.
- For DUSTREAM™ Samples
If using the DUSTREAM™ and sampling for the recommended area and time yields very little or no dust, continue sampling until the filter is 1/4 full. Our endotoxin results are not based on area, but on endotoxin Units per gram dust.
- For Extracted Samples
It is very important that we receive samples that have not been extracted. The extraction procedure must be performed in a clean environment with endotoxin free water containing 0.05% Tween. Samples should be extracted and analyzed on the same day. These steps are important in preventing endotoxin contamination from other sources.
- For Air Filter Samples
Air filter samples can also be sent in for endotoxin analysis. The whole filter is extracted in 1mL of endotoxin free water with 0.05% Tween. Results are reported as endotoxin Units per filter. We recommend sending in a blank filter for testing as well to provide a baseline for the specific filter being used.
Whether to sieve the dust or not is determined by the quality of the dust.
We do not routinely sieve dust collected from beds and soft furnishings. Carpet samples are sieved (e.g. using a No.45 mesh screen, 355um diameter sieve) to separate the fiber and large particles from fine dust.
We recommend using the DUSTREAM™ collector, which greatly reduces the need for sieving dust. After collecting a dust sample using the DUSTREAM™ collector, remove the nylon filter containing the dust sample insert, invert the filter and tap the dust onto a piece of weigh paper. The fine dust falls before the fibers come out of the filter.
Dust samples prior to extraction should be stored in a dry place at room temperature. Dust extracts should be stored frozen in a -20C freezer.
See Submitting Samples.
Download Analysis Request Form:
Standard turnaround time from sample receipt is five business days for the US lab, and 10 business days for the UK lab.
