Free radicals are normal and necessary to some degree. In addition to causing some damage, they also stimulate repair. It is only when so many free radicals are produced, and they overwhelm the repair processes, that it becomes an issue. That is what we call oxidative stress.
1 There were 178 fatalities in May (158 of those in the Joplin EF-5 tornado alone). 2  The record number of tornadoes during the month of May was 542 tornadoes set in May 2003.  The average number of tornadoes for the month of May during the past decade is 298.
It is 103% greater than the overall U.S. average. On 4/11/1965, a category F4 (max. wind speeds 207-260 mph) tornado 1.9 miles away from the Crawfordsville city center killed 28 people and injured 123 people and caused between $5,000,000 and $50,000,000 in damages.