Shin-ichi Sakai* and Hiroshi Takatsuki*

*Kyoto University, Environment Preservation Center

+ Correspondence should be addressed to Shinichi Sakai:
(Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501, Japan)

Abstract

Organic compounds, which have such characteristics as persistence, bioconcentration, semi-volatilityandtoxicity,aredefinedaspersistentorganicpollutants (POPs) . Amongtheirphysico-

chemical characteristics, the octanol-water partition coefficient, the soil adsorption equilibrium coefficient and the bioconcentration coefficient are interrelated, and degradation factors are involved. For this reason, their half-lives are fixed. Furthermore, the vapor pressure and the octanol-air partition coefficient have a great influence on the volatilization with respect to their global migration. Reflecting these physicochemical characteristics, their atmospheric distribution on a local or global scale is determined, after which the time delay up to the distribution is defined. Concerning recycling and waste management, some POPs have been intentionally manufactured for specific uses. At present it is required that waste PCBs and waste agricultural chemicals, which are included among the banned POPs, must be properly treated. Using coplanar PCB as an example, we showed that such intentionally manufactured POPs can be formed as by-products of incineration processes. The source control of unintentional by-products, including PCDDs/DFs and coplanar PCB, and the environmental cycle control are most important for total management.

Key words: Persistent Organic Pollutants (POPs), environmental persistence, vapor pressure, octanol-air partition coefficient, PCDDs/DFs, Polychlorinated Biphenyl (PCBs), waste agricultural chemicals, source control, environmental cycle control