Cancer risks in the optical manufacturing industry.

Area of Science:

• Occupational Health
• Epidemiology
• Environmental Health

Background:

• Optical lens and metal spectacle frame manufacturing involves potential exposure to various substances.
• Previous studies have not fully elucidated the cancer risks associated with these specific manufacturing processes.

Purpose of the Study:

• To investigate the association between occupational exposures in optical lens and metal spectacle frame production and cancer risks.
• To identify specific cancer types and exposure durations linked to increased mortality.

Main Methods:

• A mortality odds ratio (MOR) study was conducted using male death certificates from a Massachusetts town with a significant optical industry.
• Cancer cases were compared against cardiovascular disease as a reference, with non-optical industry workers serving as controls.
• Standardized MORs (sMOR) were calculated for different exposure durations (medium and long-term).

Main Results:

• Lens workers showed an excess risk of total cancers (observed=70, expected=48), primarily driven by gastrointestinal cancers (sMOR=2.2-2.5).
• Colorectal cancer risks were significantly elevated among lens workers with medium and long-term exposure (sMOR=3.2-2.6).
• Metal frame workers with long-term exposure exhibited excess risks for gastrointestinal (sMOR=2.9) and colorectal cancers (sMOR=3.4), though with small case numbers.

Conclusions:

• Occupational exposures, potentially abrasives or cutting oil mists, may increase the risk of gastrointestinal, particularly colorectal, cancers in lens and metal spectacle frame manufacturers.
• The findings suggest a need for further investigation into exposure pathways, such as ingestion.
• Implementing targeted occupational health and safety measures is recommended for these industries.