Lay summary
Significant excess risks of lung cancer and haematologic neoplasms have been observed in meat workers in both cohort and case-control studies conducted in several countries including New Zealand. No specific causes have been identified, although a biological cause is most likely as the risk is highest in parts of the process where workers are exposed to live animals; to animal urine; faeces and blood; or are directly involved in slaughtering. We propose a study including environmental monitoring of bioaerosols to measure proteins, urine and blood, plus methods for universal detection of pathogens in personal and area samples of workplace air; mutagenicity testing of bioaerosol samples; biological monitoring using serological testing, and sputum induction, to establish the presence of candidate microorganisms in the airways of meat workers. We will use this exposure information to update and reanalyse our existing cohort study of mortality and cancer incidence in meat workers.