Occupational exposure and 12-year spirometric changes among Paris area workers

Area of Science:

• Occupational Medicine
• Pulmonary Physiology
• Environmental Health

Background:

• Chronic airflow obstruction is a significant public health concern.
• Occupational exposures are suspected contributors to lung function decline.
• Longitudinal studies are crucial for understanding the progression of respiratory diseases.

Purpose of the Study:

• To investigate the long-term effects of occupational exposures on lung function decline.
• To assess the relationship between dust, gas, and heat exposure and the rate of forced expiratory volume in one second (FEV1) decline.
• To evaluate the impact of job changes on occupational lung disease progression.

Main Methods:

• A 12-year follow-up study of 556 male factory workers in Paris, initially aged 30-54 in 1960.
• Detailed recording of occupational exposures (dust, gases, heat) and workplace assessments.
• Estimation of annual FEV1 decline rate (FEV1 slope) and statistical analysis adjusting for age, smoking, and baseline FEV1 level (ASLA).

Main Results:

• FEV1 slope was independently associated with occupational dust exposure (mineral and grain dust), with steeper decline correlating with higher exposure intensity.
• Job changes among heavily exposed workers were associated with a less steep FEV1 slope.
• Exposure to heat and gases, particularly in combination with dust, also showed a deleterious effect on FEV1 decline.
• ASLA FEV1 slopes ranged from 44 ml/a (minimal exposure) to 60 ml/a (high dust, heat, and gas exposure).

Conclusions:

• Occupational dust exposure plays a causal role in the development of chronic airflow obstruction.
• Cessation of dust exposure demonstrates a beneficial effect on mitigating lung function decline.
• Combined exposures to dust, heat, and gases exacerbate lung function impairment.
• Worker skill level and factory-specific factors may also influence lung function decline, independent of measured exposures.