t Air pollution emissions were not continually
monitored in the Upper Silesian Industrial District
(USID), southern Poland, and data is only available
for the last 20 years. Long-lasting and severe tree ring
reductions in pines growing 5–20 km north of the
USID area recorded particularly high levels of air
pollution emissions in the period 1950–1990. Especially high amounts of reductions and many missing rings were found in the period 1964–1981. At
the same time, pines growing 60 km west of the
USID do not record deep ring reductions; this
proves that the phenomenon is of a regional nature.
Increases in infant mortality and lung, bronchial,
and tracheal cancer morbidity rates among males