September 30, 2005
The results of the FY 2004 monitoring of hazardous air pollutants conducted by local governments have been compiled together with those monitored by the Ministry of the Environment (MOE). The concentrations of nineteen substances showed the same level or declining trend.
Hazardous air pollutants might harm human health through long term exposure even if the ambient concentration is low. Since FY 1985, the MOE has monitored hazardous air pollutants. Local governments have also monitored them since FY 1997 in compliance with the Air Pollution Control Law.
At some monitoring points, the monitoring is conducted less frequently so that the annual average cannot be compared with the environmental quality standards (EQSs). However, the monitoring results at those points have been compiled together with those monitored with enough frequency, because they are important information to comprehend the ambient concentrations of hazardous air pollutants.
|1.||Substances for which EQSs are established (four substances)|
As for benzene, measurements exceeded the EQS at 5.5 % of all monitoring points, an improvement compared to 7.8 % in FY 2003. The average concentration level also showed a declining trend. Measurement of the other substances were below the EQSs at all monitoring points (Table 1).
|2.||Substances for which guideline values are established (four substances)|
The guideline values are set as a guide to reduce health risks resulting from hazardous air pollutants in the air. Measurements of nickel compounds exceeded the guideline value at 1.8% (2.6% in FY 2003) of all monitoring points, and the average concentration level showed a declining trend. Measurement of the other substances were below the EQSs at all monitoring points (Table 2).
|3.||Trend of average value of other hazardous air pollutants for which EQSs are not established (11 Substances) (Table 3).|
To control the twelve substances including benzene and trichloroethylene, the MOE and the Ministry of Economy, Trade and Industry established a Guideline for the Promotion of Voluntary Control of Hazardous Air Pollutants by Business Entities. Under this guideline, each industry group developed a nationwide and voluntary reduction plan, setting up the target at FY 2003. Also, regional and voluntary actions to curb benzene emission have been promoted in five industrial districts, in which ambient concentration of benzene is significantly high due to considerable contribution by stationary sources.
In June 2005, the MOE reviewed the results of the plans, and concluded that voluntary actions by business entities and regional voluntary actions through collaboration between local governments and business entities within the framework established under the plan would be appropriate from now instead of an effort of each individual industryl group.
The MOE will continue to examine and assess the emission volume and the concentration of hazardous air pollutants from PRTR data and monitoring results to work on countermeasures.
|*||Environmental Quality Standards for Benzene, Trichloroethylene, Tetrachloroethylene and Dichloromethane|
|*||Guideline Values for Hazardous Air Pollutants to Reduce Health Risks|