This research was composed of two main parts.
Firstly, metal mercury concentration in air of the total 10 fluorescent lamp manufacturing industries, and in urine and in blood of the total of 815 workers, was measured and evaluated in accordance with some contributing variables.
Secondly, in order to evaluate the effectiveness of environmental intervention of two industries among the above, differences in mercury concentration sampled before and after the interventions were evaluated.
Samples included air samples of work environments and those of urine of workers in two industries.
@ES The results were as follows.
@EN 1. Among 196 air samples, 39.8% exceeded metal mercury TLV (Threshold Limit Value) of Korea, 0.05mg/㎥, and average mercury concentrations by work site were 0.069±0.038mg/㎥ in exhaustion site the showing highest level, and it declined as
the
distance from exhaustion site increased.
2. Average mercury concentration in air of exhaustion site was the highest at floor level showing 0.078±0.036mg/㎥ and the concentration at the level of worker's breathing zone and vacuum exhaustion pump also exceeded the metal mercury TLV.
3. Mercury concentration in urine of 15 workers (1.9%) among 792 workers exceeded dignostic criteria level of 300μg/l, and of 411 workers (51.9%) exceeded warning level of 50μg/l.
Average mercury concentration in urine of workers was the highest in workers of exhaustion site showing 140.4±88.2μg/l and it declined as the distance from the exhaustion site increased.
4. Among 263 workers, 5 workers (1.9%) showed higher level of blood mercury concentration than 20μg/l which was said to be dignostic criteria level in Korea, and 100 workers (38.0%) showed higher than 3.5μg/dl of warning level.
5. Among correlation coefficients between urinary mercury concentration and some contributing variables, the highest was 0.74 which related with the numbers of lamp destroyed per month, and 0.67 with the amount of mercury consumed per lamp, 0.63
with
the amount of mercury treated by person in order.
6. Average mercury concentrations in air before the intervention were the level over the TLV, but they decreased after finishing the intervention reaching below the TLV level, showing effectiveness rate of intervention to be 57.3%. Average
concentration
in urine of workers also decreased after the intervention was half of it.
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