Cresson H. Kearny, the author of the NWSS book, also states about this now declassified incident:

"It produced fallout that by January 1, 1967 resulted in the fallout cloud covering most of the United States. This one Chinese explosion produced about 15 million curies of iodine- 131 - roughly the same amount as the total release of iodine- 131 into the atmosphere from the Chernobyl nuclear power plant disaster."
"Fallout from the approximately 300 kiloton Chinese test explosion shown in Fig. 1 (Map 'B' above) caused milk from cows that fed on pastures near Oak Ridge, Tennessee and elsewhere to be contaminated with radioiodine, although not with enough to be hazardous to health."

"However, this milk contamination (up to 900 picocuries of radioactive iodine per liter) and the measured dose rates from the gamma rays emitted from fallout particles deposited in different parts of the United States indicate that trans-Pacific fallout from even an overseas nuclear war in which "only" two or three hundred megatons would be exploded could result in tens of thousands of unprepared Americans suffering thyroid injury."

"Perhaps the first nuclear war casualties in the United States will be caused by fallout from an overseas nuclear war in which our country is not a belligerent. As the number of nations with nuclear weapons increases - especially in the Middle East - this generally unrecognized danger to Americans will worsen."