Abstract：
Following the introduction of lead-free frangible ammunition in United States Air Force small arms firing ranges, Combat Arms instructors have routinely reported experiencing adverse health symptoms during live fire training exercises, including sore throat, cough, and headache. Previous studies have found that these symptoms occur despite occupational exposure limits not being exceeded. To better characterize the potential source and mechanisms for health symptoms, a comprehensive characterization of the physicochemical properties of gases and aerosols emitted during the firing of the M9 pistol and M4 rifle using lead-free frangible ammunition was completed. Weapons were fired within a sealed chamber using a remote firing mechanism. A suite of direct-reading instruments and collection-based analytical methods were used to determine the composition of the emissions. Emissions were dominated by carbon monoxide and ultrafine particles. Other prevalent gases included carbon dioxide, ammonia, formaldehyde, hydrogen cyanide, and nitric oxide when measured using Fourier-transform infrared spectroscopy. An electrical, low-pressure impactor showed that, on average, the count median diameter immediately after firing was 36 ± 4 nm (n = 10 rounds) and 32 ± 3 nm (n = 14 rounds) for the M9 pistol and M4 rifle, respectively. Analytical methods were used to determine that emitted particles were primarily composed of soot, copper, and potassium, with trace amounts of calcium, silicon, sodium, sulfur, and zinc. Results from this research confirm prior work and expand upon the characterization of emissions generated from firing lead-free frangible ammunition. By employing multiple methods to measure and analyze data we were able to quantify both total and respirable particle fractions and determine particle morphology and composition. Characterization of the emissions provides insight into potential exposure risks that may lead to the development of adverse health symptoms allowing for the development of strategies for risk mitigation.
摘要：
美国空军小武器射击场引进无铅易碎弹药后,战斗武器教官经常报告在实弹训练演习中出现不良健康症状，包括喉咙痛,咳嗽,和头痛。先前的研究发现，尽管未超过职业暴露限制，但仍会出现这些症状。为了更好地表征健康症状的潜在来源和机制，完成了对使用无铅易碎弹药发射M9手枪和M4步枪期间排放的气体和气溶胶的物理化学性质的全面表征。使用远程射击机构在密封的室内发射武器。使用了一套直接读取仪器和基于收集的分析方法来确定排放物的组成。排放主要是一氧化碳和超细颗粒。其他常见的气体包括二氧化碳，氨,甲醛,氰化氢,和使用傅里叶变换红外光谱法测量时的一氧化氮。一个电气，低压冲击器显示，平均而言,M9手枪和M4步枪射击后立即计数中值直径为36±4nm（n=10发）和32±3nm（n=14发），分别。使用分析方法来确定排放的颗粒主要由烟灰组成，铜，钾，含有微量的钙，硅，钠,硫磺,和锌。这项研究的结果证实了先前的工作，并扩展了发射无铅易碎弹药产生的排放特征。通过采用多种方法来测量和分析数据，我们能够量化总颗粒和可吸入颗粒部分，并确定颗粒形态和组成。排放物的表征提供了对可能导致不良健康症状发展的潜在暴露风险的见解，从而可以制定减轻风险的策略。
