Introduction

Over time, common building and maintenance materials can begin to release several chemicals that are known and/or suspected of being toxic to humans and non-human animals. Though we have discontinued the days of asbestos insulation and lead paint, the substitutes and undiscovered contaminants may be just as harmful. For example, polycyclic aromatic hydrocarbons (PAHs) are used as a primary component in the tar used for roofing in many buildings and are suspected of being carcinogenic. Studies have found that high levels of exposure can cause tumors and reproductive problems in rats. Furthermore, the polybrominated diphenyl ethers (BDEs) used as flame retardants in electrical cables and and insulation have also been thought to be carcinogenic. Additionally, insecticides tend to be used indoors as pest controllers and can be harmful to humans in large doses. The EPA classifies many insecticides as possible carcinogens and warns against their effects on the human nervous system.

Objective

Previous research has shown that PAHs, BDEs, and insecticides are common contaminants within Hispanic homes. Thus, my research objective was to determine the concentration of these contaminants in buildings on the Oklahoma State University campus. By diversifying our collection areas, we anticipate to further identify the regions in which the public may experience exposure to environmental contaminants.

Table 2: Method details.

Methods

Sampling: •  Using a 10cm x 10cm polyethylene template, 100 cubic centimeters were sampled in ten separate buildings by rubbing an isopropyl alcohol dampened wipe across the selected walls. • One wipe was put aside to be used as a control. • 10 mL of Ethyl Acetate and around 1500 mg of sodium sulfate were then added to a vial with each wipe collected to extract the samples. • All samples were gently shaken by a pulsating water bath and then extracted (using a pipet) into smaller test tubes. • All 11 samples were evaporated down to 1mL using nitrogen gas and place within a 2mL vial. • Sites sampled are shown in Table 1. Preparations for Testing: • After overnight refrigeration, 25µl of internal standards were placed into each vile using a micropipette . • A standard dilution curve was made that contained all analytes at concentrations ranging from 30-3000 ng/ml. • These samples were also then refrigerated overnight. Calibrations: • To ready the gas chromatograph/mass spectrometer for testing, the GCMS was calibrated to search for certain ions that matched the ions of PAHs, BDEs, and insecticides within the samples at predetermined retention times (Table 2) • These retention times were based upon the times and temperatures at which the gaseous chemicals are known to be eluted from the methyl siloxane column (Table 2). • Once finished calibrating, the samples were analyzed.

Table 1:

List of sites tested and sample details

Reten.on)Time)(Min))

Ions:)Quan.ta.ve/ Qualita.ve)

Benz(a)anthracene, Benzo(k)fluoranthene, Benzo(b)fluoranthene, Benzo(a)pyrene,

PAHs%% 14.01, 16.86, 16.82, 17.48,

228/226,229, 252/250, 252/250, 252/250,

Indeno,(1,2,3,Ccd),pyrene,

20.02,

276/277.274,

Dibenzo,(a,h),anthracene,

20.18, BDEs% 12.14, 14.71, 16.58, 16.58, 19.29, 19.29, 21.29, 13.04, INSECTICIDES% 14.87, 17.78, 16.86, 7.2, 9.39, 16.03,

278/279,276,

Chemical)Class)

BDE,28, BDE,47, BDE,99, BDE,100, BDE,153, BDE,154, BDE,183, TDCPP, Bifenthrin, Cypermethrin,1, Permethrin, Diazinon,, Chlorphyrifos, Lambda,

Results Sample%Site%

Loca8on%of%Sample%

Notes% Test,preformed,on,concrete, block,surface, Test,preformed,on,Sled,wall, surface,

Physical,Sciences,

Third,Floor,,

Engineering,North,,

Second,Floor,

Library,

Third,Floor,

Library,,

Fourth,Floor,

Murray,Hall,

Third,Floor,

Rough,surface,tested,

Gundersen,Hall,

First,Floor,

Rough,surface,tested,

Morrill,Hall,

First,Floor,

Smooth,surface,tested,

Seretean,,

First,Floor,

Brick,surface,tested,

Old,Central,

Second,Floor,

LSW,

Fi\h,Floor,

Tiled,surface,tested,

181/166, 163/181, 183/163, 137/153,179, 197/314,199, 181/197,208,

TDCPP, a flame retardant, was the only compound that was found in significant concentrations. The sample taken from physical sciences had the highest concentration at 52.61ng per 100cm. 15ng was the average for all samples. All other analytes were below quantitation limits.

Wall,recently,painted,green, East,wing,C,Next,to,emergency, exit,

Older,wooden,surface,tested,

406/246,408, 326/486, 564/404,566, 564/404, 484/644,482, 484/644,482, 562/722,564, 381/191,193,

Figure 1:

Example chromatogram showing results from Engineering North