129I from the nuclear reprocessing facilities traced in precipitation and runoff in northern Europe

A huge amount of radioactive I-129 has been released into the environment from the nuclear energy industry, atomic weapon tests, and nuclear accidents. In this study, we present weekly and seasonal data on I-129 measured in precipitation and runoff of northern Europe during 1998 and 1999. The I-129 concentration is at 10(8)-10(9) atoms/L in precipitation and (2-5) x 10(8) atoms/L in runoff water, and it is 3-4 orders of magnitude higher than in the prenuclear era. Snow shows lower O-129 concentration than rain, and there is apparently a positive correlation between surface air temperature and I-129. Precipitation chemistry, expressed as the content of CI, SO4, and NO3 and atmospheric ozone, exhibits weak negative correlation with I-129 values. Our I-129 data on precipitation suggest significant influence of the northern European atmosphere by the discharges from the nuclear reprocessing facilities at Sellafield and La Hague.