日本申请进驻日美军基地调查污染源 美军：不同意

Core Viewpoint - The U.S. military has officially rejected Japan's request to investigate potential pollution sources related to per- and polyfluoroalkyl substances (PFAS) detected near U.S. military bases in Okinawa, despite multiple requests from local authorities since 2016 [1][3][6] Group 1 - The Japanese Defense Ministry communicated to Okinawa Prefecture that the U.S. military has formally declined the request for an investigation into pollution sources [1][3] - Okinawa Prefecture has made four requests since 2016 to enter U.S. military bases for investigations, but has not received a response until now [3][6] - The U.S. military cited a lack of scientific evidence linking the bases to the contamination and noted the absence of unified standards for assessing water and soil sample pollution levels [3][6] Group 2 - Experts in Okinawa have concluded that the U.S. military bases are likely sources of the contamination, and the prefecture will continue to seek access for investigations [6] - PFAS are a group of thousands of chemical substances that are persistent in the environment and human body, often referred to as "forever chemicals" [6] - The U.S. Centers for Disease Control and Prevention (CDC) has indicated that these substances may lead to various health issues, including kidney cancer and elevated cholesterol levels [6] - Recent water quality investigations in Okinawa revealed that PFAS levels exceeded safety limits in two locations near U.S. military bases [6]