Authors surveyed the ground water near the waste disposed from a fiberglass production factory to confirm the presence of glassfiber in the water and to determine the effect of sampling conditions and storage on the recovery of fibrous materials in the ground water.
Sample was collected at every 4 hours for 48 hours consecutively. After finishing the 48 hours sample, water sampling was done from each tap after repeated turning on and off the water for 30 seconds at each time. Sample was collected in the two 1.5 liter polyethylene bottle after vigorously shaking the bottle with the same water several times with the flowing tap water. At each paired sample, one bottle was stored stand still at room temperature, and the other sample was filtered immediately after sampling. Water was filtered on the Mixed Cellulose Ester filter with negative pressure. Each sample was divided into upper and lower layer. The other bottle was stored at room temperature standstill for 7 days and filtered in the same fashion as the other pair of sample did. Each MCE filter was divided into 4 pieces and one piece was treated with acetone to make it transparent. Each prepared sample was observed by two researchers under the light and polarizing microscopy, scanning electron microscopy and energy dispersive X-ray microanalysis. Fibers were classified by the morphology and polarizing pattern under the polarizing microscope, and count was done.
1. There was a significant fluctuation in number of the fibers, but there was no specific demonstrable pattern.
2. Non-polarizing fibers frequently disappeared after 7 days´s storage. But cluster of fibers were found at the wall of the same container by scratching technique.
3. Polarizing fibers were usually found in between the filter and the manicure pasted area. Possible explanations for this phenomenon wilt be that either these fibers are very light or have electronic polarity. Hence, these fibers are not able to he attached on the surface of slide glass.
4. Under the scanning electron microscopic examination, the fibers which are not refractive under the light microscopy were identified as glassfiber. Other fibers which is refractive under the polarizing microscopy were identified as magnesium silicate fibers.
It is strongly suggested that development of standardized method of sample collection and measurement of fibrous material in the water is needed.
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