| 英文摘要 |
There is a growing need for chemical analysis of toxic chemical substances in order to support the administrative actions under the amended Toxic and Concerned Chemical Substances Control Act. This project aims to develop the needed analytical capabilities via the tasks including completing the analytical method database and the acquirement of the standard materials, learning from the international operations of the laboratory management for chemical substances, assessment of the aquatic toxicity, sampling and analysis of chemical substances from factories, and submission for accreditation of 33 chemical substances. Besides, benefits from this project were analyzed and the follow-up tasks in the near future were also proposed.
To complete the analytical method database, relevant methods for the 51 toxic substances, which lack domestic standand methods, and 20 candidates of the concerned chemical substances can be found from the sources listed in Article 14 of the “Management and Operation of Toxic Chemical Substances and Regulations”. However, some of the methods analyze the toxic groups of concern instead of the individual compound, whereas the concentration of the individual compound shall be on demand based on our regulation in Taiwan. Although analytical methods for the individual compound may be studied, it was suggested to consider adopting group regulations for those whose toxicity concerns are only associated with the particular groups. As for the standard materials not available in the regular commodity channel, obtaining from the users is a doable way as long as the certificate of analysis can be provided.
As for the operation system of the laboratories in countires such as those of European Uion, the U.S., Korean and Japen, laboratories compliance with Good Labortory Practice (GLP) are qualified for chemical substance analysis. GLP is a quality system of management controls without limitations on the analytical methods used. For laboratories, this way of operation provides the needed flexibility in order to analyze hundreds of chemical substances that may come in different ways. On the contrary, for the environmental sample analysis, laboratories must obtain the accreditation of the analytical method specific to the target compounds in the matrix of the samples. While there are two different operation systems in these foreign countries, there is only one syetem in Taiwan, which is similar to that aforementioned for the environmental sample analysis. Fortunately, the NIEA T101 and NIEA T102 methods specific for chemical substances announced in recent years by Taiwan EPA provide the flexibility similar to that of GLP and thus are very helpful for the development of the analytical capability of chemical substances.
Assessment of aquatic toxicity was conducted using daphnia and carp to evaluate the acute toxicity of volitle organic chemicals. Evaluation was performed in a close system with little headspace based on the test method recommended by OECD. Results showed that over-estimation of LC50 or EC50 can be minimized in close systems compared to open systems. Besides, it was recommended that EC50 be defined based on immobility instead of death.
In order to understand how the chemical substances are handled in the industries, 33 compounds were chosen as targets in this work and 30 factories handling at least one of the targets were visited. A total of 203 samples containing more or less the targets were sampled from the factories and analyzed by 2 laboratories, which completed the submission of accreditation application by the end of this project. Some of the analysis results were not consistent with the claimed concentrations on safety data sheets (SDS) provided by the factories, and frequently a certificate of analysis with data quality quarenteed was not available. It was suggested that chemical handlers should have certificates of analysis as a legal proof of the concentration especially when the toxic chemical substances are contained. With the experience of taking samples of various toxic chemical sunstances from industries, we incorporated the advices from several experts and completed a draft of Handbook of Sampling, Screening and Analysis for Chemicals. We also managed a training course and shared these experiences with the local enforcement officers.
Benefits of this project include enhancing the safety of chemical substances and promoting the needs and market of screening and analysis of chemical substances, not to mention a significant progress in the development of the domestic analytical capability. In the future, efforts to improve are still needed and a 4-year blueprint was presented in this work with focuses on the directions including both regulations and technical enhancement.
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