Lead exposure in indoor firing ranges.

Higher air lead levels (time-weighted average 660, range 112-2238 micrograms/m3) were measured in firing ranges where powder charges were employed than in ranges where air guns were used (4.6, range 1.8-7.2 micrograms/m3); levels in the latter were in turn higher than those in ranges used for archery (0.11, range 0.10-0.13 micrograms/m3). Twenty-two marksmen who used powder charges had significantly increased blood lead levels during the indoor shooting season (before: median 106, range 32-176 micrograms/l; after: 138; range 69-288 micrograms/l; P = 0.0001), while 21 subjects who mainly used air guns displayed no significant increase (before: median 91, range 47-179 micrograms/l; after: 84; range 20-222 micrograms/l). Thirteen archers had significantly lower levels than the pistol shooters before the season (P = 0.006), and showed a significant decrease during the season (before: median 61, range 27-92 micrograms/l; after: 56; range 31-87 micrograms/l; P = 0.04). At the end of the indoor season, there was a significant association between weekly pistol shooting time and blood lead levels.