Mortality of Workers in Two Minnesota Taconite Mining and Milling Operations

Abstract

Recent studies have shown that taconite workers may be at increased risk for mortality from lung cancer, mesothelioma, and cardiovascular diseases (CVD). The relationship between CVD and occupational dust exposures at these mines has not been well-studied. We conducted an air monitoring campaign to char-acterise fine aerosol concentrations at 91 locations across six taconite mines using direct-reading instruments to obtain measurements of mass concentrations (PM 2.5 or particles with aerodynamic diameter less than 2.5 mm, and respirable particulate matters or RPM), surface area (SA), particle number (PN), and particle size distributions. We fit a Bayesian model with an AR (1) (autoregressive order 1) correlation structure to estimate exposure while accounting for temporal correlation. The highest estimated geometric means (GMs) were observed in the pelletiz-ing and concentrating departments (pelletizing maintenance, ball-ing drum operator, and concentrator operator) for PM 2.5 and RPM. SA and PN generally had highest GMs in the pelletizing department that processed powder-like particles into iron pellets. Between-location variability estimates were generally higher than within-location, indicating larger differences in exposure levels at different locations between mines. Ranking between PM 2.5 and RPM generally agree with each other, whereas SA and PN were more consistent with each other, with some overlap with PM 2.5 and RPM. Differences in ranking these groups may have potential implication for occupational epidemiological studies that rely on exposure information to detect an exposure-response relationship. Future occupational epidemiological studies investigating fine aerosols exposures and health risk are encouraged to consider multiple metrics to see how they influence health outcomes risk.

Mortality experience among Minnesota taconite mining industry workers

“…The study showed no increases in observed respiratory cancers compared to the USA and Minnesota. Cooper et al 17 18 studied mortality through 1988 in a cohort of 3431 male workers from Erie and Minntac mines between 1959 and 1977. Total observed deaths were fewer than expected when compared to US and Minnesota death rates.…”

“…The authors reported no increased risk of respiratory cancers among the 5751 miners. Later, studies were conducted in 1988 with an update in 199217 18 and, similarly, did not report an excess mortality among the 3431 workers from Erie and Minntac mines. In 1997, the Minnesota Department of Health Cancer Surveillance System reported a 73% excess in cases of mesothelioma among men in the northeastern region of Minnesota between 1988 and 1996 as compared with the rest of the state 19.…”

Nonmalignant Asbestos-Related Disease: Diagnosis and Early Management

“…58,59 Most studies show a relatively large and significant relative risk [60][61][62][63][64] or elevations that do not achieve statistical significance. 65 Only one shows no evidence of elevation. 66 Recently published results from the CARET study also support that colorectal cancer risk is elevated among men occupationally exposed to asbestos, after controlling for smoking.…”

Dual Renin-Angiotensin-Aldosterone System Inhibition for the Treatment of Diabetic Kidney Disease: Adverse Effects and Unfulfilled Promise

“…Approximately 39 % of patients with chronic kidney disease have DM and 41-44 % of all new cases of ESKD are due to DN. The 5-year survival of diabetic patients on dialysis is only 34 % [5].…”

“…Despite increases in the prevalence of DM in the last decade, it is reassuring that the incidence of DN has been declining since 2006 [5]. The recent decline in the incidence of DN has been attributed to better glycemic management, blood pressure control, and widespread use of renin-angiotensin-aldosterone system (RAAS) blockade [4,6].…”