Respiratory Health and Urinary Trace Metals among Artisanal Stone-Crushers: A Cross-Sectional Study in Lubumbashi, DR Congo.

BACKGROUND: Thousands of artisanal workers are exposed to mineral dusts from various origins in the African Copperbelt. We determined the prevalence of respiratory symptoms, pulmonary function, and urinary metals among artisanal stone-crushers in Lubumbashi. METHODS: We conducted a cross-sectional study of 48 male artisanal stone-crushers and 50 male taxi-drivers using a standardized questionnaire and spirometry. Concentrations of trace metals were measured by Inductively Coupled - Plasma Mass Spectrometry (ICP-MS) in urine spot samples. RESULTS: Urinary Co, Ni, As, and Se were higher in stone-crushers than in control participants. Wheezing was more prevalent (p = 0.021) among stone-crushers (23%) than among taxi-drivers (6%). In multiple logistic regression analysis, the job of a stone-crusher was associated to wheezing (adjusted Odds Ratio 4.45, 95% Confidence Interval 1.09-18.24). Stone-crushers had higher values (% predicted) than taxi-drivers for Forced Vital Capacity (105.4 ± 15.9 vs. 92.2 ± 17.8, p = 0.048), Forced Expiratory Volume in 1 Second (104.4 ± 13.7 vs. 88.0 ± 19.6, p = 0.052), and Maximum Expiratory Flow at 25% of the Forced Vital Capacity (79.0.1 ± 20.7 vs. 55.7 ± 30.1, p = 0.078). CONCLUSION: Stone-crushers were more heavily exposed to mineral dust and various trace elements than taxi-drivers, and they had a fourfold increased risk of reporting wheezing, but they did not have evidence of more respiratory impairment than taxi-drivers.

Holoprosencephaly: A case series from an area with high mining-related pollution.

BACKGROUND: The extraction and processing of copper and cobalt in the African Copperbelt in the Democratic Republic of Congo have led to substantial environmental pollution, causing concerns about possible adverse effects on human health, including birth defects. CASES: We report three neonates with clinically diagnosed holoprosencephaly who were part of a case-control study performed in Lubumbashi between February 2013 and February 2015. One mother had a high concentration of uranium in urine, and high manganese concentrations were found in blood of another mother and in cord blood of one infant. Two of the three fathers had a mining-related job. DISCUSSION: We hypothesize that these cases of holoprosencephaly were connected to mining-related pollution, possibly via epigenetic alterations induced by paternal occupational exposure to toxic metals.