Using Urinary Thiodiglycolic Acid (TDGA) To Assess The Exposure Of Vinyl Chloride Monomer (VCM) In School-Aged Children Nearby A Vcm Manufactory In Central Taiwan

Abstract

Introduction. In 2013, one elementary school was relocated to a new campus nearby (< 1 km, school A) a vinyl chloride monomer (VCM) manufactory in central Taiwan. We aim to assess the exposure of VCM in these school-aged children using urinary thiodiglycolic acid (TDGA), the suggested biomarker of VCM by ATSDR. Materials and Method. Five elementary schools were selected as our study sites within a 10 km distance closed to a petrochemical complex in central Taiwan. We invited six volunteer boys and girls, respectively, at each grade (one to six) from two schools (< 3km), and matched for age and gender for recruitment of students at the other three schools. After an informed consent was obtained, we collected their first morning urine sample by plastic urine bag (PP), drawed their blood samples and filled a questionnaire from each subject on Wednesday during October 2013 to April 2014. We analyzed TDGA in urine sample of each participant using liquid chromatography tandem mass spectrometry. Blood sample was analyzed for confirmation of hepatitis B virus (HBV) infection. Results and discussion. We totally recruited three hundreds and fourty-three students from five elementary schools. Only one student got HBV infection and 1.9% of participants have consumed vitamin B in the past one month. Mean levels of urinary TDGA in participants at school A and other schools by distance were 192.8, 101.1, 120.6, 116.0 and 61.0 μg/g creatinine, respectively. After adjustment for age, gender, BMI, HBV infection, vitamin B consumption, passive smoking, home location and etc., we found that the mean level of urinary TDGA at school A was significantly (P