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Saturday 20, November, 2004 13:30 - 15:30, No.2 Conference Room Workshop E Epidemiology and Public Health Chairs: Gunnar Hillerdal and Kohki Inai Reza Gholamnia1, S.B. Mortazavi2, Hasan Asilian2, Ali khavanin2 , Yahya Rasoulzadeh1 1Uromia of Medical Science University, Uromie, Iran [not- attended, paper submission] 2Tarbiat Modares University, Tehran, Iran ABSTRACT Introduction Due to definite pathogenicity of asbestos, human have thought a appreciate alternative for asbestos with a like chemical properties and none or less pathoginicity and less hazards. Synthetic vitreous fibers are an important substitute for asbestos in a variety of products where thermal and acoustical is required. Due to numerous uses, it is important exposure rate of worker and other persons that deal with directly in production, transportation and handling. In fact, like man-made fibers with asbestos due to morphological fiber, microscopic appearance, application and large uses in industry lead to concern that such fibers may cause health effects like asbestos. Occupational exposure to fibers has been associated with irritation skin and respiratory tract. One of the objectives of this study was determine occupational exposure with Rockwood fibers and survey volumes and capacities respiratory. Material and Methods The standard method for the determination of airborne fibrous particles in the workplace is NIOSH Method 7400 by Phase Contrast Microscopy. According to this method, samples are collected on 25-mm cellulose ester filters. The filter is treated to make it transparent and then is analyzed by microscopy at 400-450x magnification, with phase-contrast illumination, using a Walton-Beckett graticule. Using counting rules B, only fibers <3 ƒÊm in diameter and >5 ƒÊm in length with aspect ratios of 5:1 are counted. Pulmonary function test is carried out by P.F.T spirometer to obtain VC and FVC test. Questionnaire respiratory is completed for case - control groups. In this case, administrative staff and production workers are elected as case and control groups respectively. The respiratory questionnaire is filled to both groups. The FVC and VC maneuver is performed. Results and Discussion The result of counting fiber had determined different level in worker's breathing zone.Mean of exposure TWA 8 hours and actual exposure is 0.51 and 0.7 fiber/cc, respectively. Occupational exposure has not exceeded to TLV-TWA (ACGIH) and T-test has not determined significantly different with occupational exposure level (P < 0.001). Due to overtime, occupational exposure was high and T-Test has revealed significantly different with OEL (p = 0.001). The results are showed that the significantly different has been between mean of VC, FVC and FEV1 in groups but there are significantly different to normal range (P< 0.001). Then our study showed that rockwool fiber has not too influenced on volumes and capacities respiratory. But, in spite of the fact that, the respiratory sign such as cough, phlegm is caused due to inhalation fiber. Pervious studies confirm our findings. In fact, irritation sings due to inhalation rockwool fiber is accomplished with cough, phlegm, wheezing and breathlessness. The correlation test is revealed that there is significantly correlation between smoking and respiratory signs such as phlegm (r = 0.29, P= 0.006), cough (r = 0.25, P = 0.02). KEY WORDS: Rock wool, Counting Fibers, Volumes and capacities respiratory, Spirometery. |