Excluding workers with more than 1280 μg/m 3 years produces a highly significant ( p < 0.001) model with an E-R slope of 4.06 (2.11–7.83) per 1000 μg/m 3 years (or 1.0014), and is the only significant model after exclusion of high exposures and workers with <5-years tenure.
E-R trends are marginally significant for squamous and large cell carcinomas (or not significant if multiple testing is taken into account) and E-R associations are uncertain because of weakly positive but statistically non-significant E-R trends.
Subsequent analyses stratified by worker location then resulted in no trend for surface workers, a clear trend for UG workers, and a nonsignificant trend for the complete cohort when adjusted for worker location ( Figure 8 ).
The authors specifically note the limitation of the general population job-exposure-matrix (DOM-JEM) used in this study: “The high prevalence of exposure is also a consequence of the nature of a JEM, namely to assign everybody in a given job code the same exposure, whereas individual assessments give the opportunity for attributing exposure to some people in a job but not others, and to take into account an increasing trend of diesel engines over time.
We conclude the German potash miner study does not support the diesel hypothesis because there is no significant E-R trend, and the suggestion of a possible trend is removed by adjustment for radon exposure in uranium mining and the very low lung cancer mortality in the referent group.