Compared with the exposure data reviewed by Kamijima et al. (2007), the environmental exposure concentrations in the present study were relatively high.
Study physicians at the NHS and HPFS who were masked to the exposure data reviewed medical records and assigned cancer diagnoses and causes of death.
The fact that the large body of controlled human exposure data has been reviewed and/or relied upon numerous times for establishing formaldehyde air levels to prevent the symptoms of sensory irritation by regulatory and authoritative bodies worldwide (e.g., US EPA, NAS, Canada's Health Canada, Australia's NICNAS, Germany's BFR, OECD, WHO), attests to their validity and usefulness.
Two study physicians (gastroenterologists) blinded to exposure information, reviewed and extracted the data based from hospital records, discharge summaries, endoscopy reports and pathology reports if biopsy specimens were taken.
The original group invested considerable time in reviewing exposure data, the populations involved, and possible health outcomes.
No study in this review gathered exposure data for all potential sources.
Although tobacco smoke exposure data were limited in this review, environmental tobacco smoke is reported to be present in ~90% of Nunavut homes, which are small, overcrowded and have low air change rates [ 39].
Although the numbers of asbestos-related diseases were expectedly low, given the rigorous review of exposure data adopted by Nelson, it is interesting that there were, in actual fact, ANY cases with asbestosis or asbestos pleural disease – both of which require substantial exposure over a long period of time.
A study physician blinded to the woman's exposure and intake data reviewed all records and extracted data on the histologic type, anatomical location, and stage of the cancer.
In 2013, the International Journal of Environmental Research and Public Health (IJERPU) published an article, Domestic Asbestos Exposure: A Review of Epidemiologic and Exposure Data [ 22].
Alcohol exposure data were collected at the interview or from a review of available study data.
