chronic exposure

基本解释

Doctors believe that heredity and chronic exposure to loud noises are the main factors that contribute to hearing loss.
医生们认为遗传因素和长期处于高分贝的嘈杂环境是导致失聪的主要因素。
Acetylene is a simple asphyxiant and anesthetic. Experiments have shown there to be no harmful effects from chronic exposure to acetylene at high concentrations.
乙炔是简单的窒息物和麻醉剂。实验显示慢性接触高浓度乙炔没有有害影响。
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Chronic exposure and action level;
慢性照射和行动水平；

It is important to mention that this condition is not a burn, but just a skin condition that develops as a result of chronic exposure to moderate heat.
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If you have a history of asthma or emphysema, (COPD) or other chronic lung disease, limit your exposure to the cold temperatures.
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Doses may be chronic or acute depending upon the duration of exposure.
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