Comparison of wipe materials and wetting agents for pesticide residue collection from hard surfaces

Abstract

Different wipe materials and wetting agents have been used to collect pesticide residues from surfaces, but little is known about their comparability. To inform the selection of a wipe for the National Children’s Study, the analytical feasibility, collection efficiency, and precision of Twillwipes wetted with isopropanol (TI), Ghost Wipes (GW), and Twillwipes wetted with water (TW), and were evaluated. Wipe samples were collected from stainless steel surfaces spiked with high and low concentrations of 27 insecticides, including organochlorines, organophosphates, and pyrethroids. Samples were analyzed by GC/MS/SIM. No analytical interferences were observed for any of the wipes. The mean percent collection efficiencies across all pesticides for the TI, GW, and TW were 69.3%, 31.1%, and 10.3% at the high concentration, respectively, and 55.6%, 22.5%, and 6.9% at the low concentration, respectively. The collection efficiencies of the TI were significantly greater than that of GW or TW (p<0.0001). Collection efficiency also differed significantly by pesticide (p<0.0001) and spike concentration (p<0.0001). The pooled coefficients of variation (CVs) of the collection efficiencies for the TI, GW, and TW at high concentration were 0.08, 0.17, and 0.24, respectively. The pooled CV of the collection efficiencies for the TI, GW, and TW at low concentration were 0.15, 0.19, and 0.36, respectively. The TI had significantly lower CVs than either of the other two wipes (p=0.0008). Though the TI was superior in terms of both accuracy and precision, it requires multiple preparation steps, which could lead to operational challenges in a large-scale study.

The effect of reusing wipes for particle collection

“…The screening technique that commonly utilizes dry wipe sampling in these security settings is ion mobility spectrometry (IMS), which is often chosen due to its sensitivity, rapid analysis time and ease of use. While biological and environmental screening often uses wet wipes for collection and then extraction for an analytical procedure [ 3 , 14 , 15 ], the wipes for IMS screening must be dry to avoid chemical interferences with the IMS technique [ 5 ]. In the last decade, there have been tens of thousands of these instruments deployed worldwide in airports alone [ 4 ].…”

Feasibility and informative value of environmental sample collection in the National Children's Vanguard Study

“…The low analyte detection frequency with wipe samples also has been observed in the American Healthy Homes Survey (AHHS) (Stout et al, 2009). The informative value of the wipe samples could be improved by changing the wipe wetting agent from water to isopropanol (Deziel et al, 2011). Alternatively, pesticide wipe samples could be replaced with bulk dust collection, which has been shown to yield higher detection frequencies (Colt et al, 2005).…”

A test house study of pesticides and pesticide degradation products following an indoor application

“…The efficiency of the wipes in recovering pesticides from a stainless steel surface has been reported previously (Deziel et al., ). In the current study, only the accuracy and precision of sample processing was evaluated.…”