The following variables were extracted from the PATHAUT database for 1975 2007: population group, duration of gold mining employment, age at death, and whether silicosis was present at autopsy.
In comparison to the trucking industry, the duration of underground mine exposure was relatively short (a mean of 8 years compared with a mean of 21.6 years in the present study) but more intense, with mean EC exposures of 128 µg/m compared with the historical trucking industry's lower cross-shift estimates noted previously.
Thus, over the 15-year projected duration of a single mining operation, nodule mining might severely damage abyssal seafloor communities over areas of 20,000 to 45,000 km² (a zone at least the size of Massachusetts).
Increased risks of lung cancer in relation to duration of underground hard rock mining have also been described in other cohorts.
The average duration of employment in gold mining for the black miners was 7.7 years (median, 6.1 years; range, 1.1 48.0 years), and that for white miners was 17.1 years (median, 15.0 years; range, 1.1 54.0 years) for white miners.
Calculated according to the duration of surface movement and deformation, mining activities in this region should have lasted for around 6 years.
This newer source contrasts in duration of exposure with the lead mining and smelters found in areas of Australia such as Broken Hill and Port Pirie.
Potential risk factors for the development of silicosis were considered to be age at death and duration of employment in the gold mining industry (as proxy measures of dust exposure in the absence of dust measurements), and year of autopsy.
Her hand and mine found the Eggy Stone at the same moment, our fingers touched, and somehow that sealed it: I was hers and she was mine for the duration of the holiday.
Mine for the duration of the trip was lean, enthusiastic, vastly experienced and proud of his boast of being the only person of Zambian descent to be born Andorran.
