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In the place you do research: What are mercury contamination levels in waterways?

Monday, July 29, 2019 - 6:55am

Gerson et al. measured THg and MeHg concentrations in soil (n = 119), sediment (n = 22), and water (n = 25) from four active artisanal small-scale gold mining (ASGM) villages and one non-ASGM reference village in Senegal. Nearly all samples had THg and MeHg concentrations that exceeded the reference village concentrations and USEPA regulatory standards. The highest median THg concentrations were found in huts where mercury-gold amalgams were burned (7.5 μg/g), while the highest median MeHg concentrations and percent Hg as MeHg were found in river sediments (4.2 ng/g, 0.41%). Median river water concentrations of THg and MeHg were also elevated compared to values at the reference site (22 ng THg/L, 0.037 ng MeHg/L in ASGM sites). This study provides direct evidence that Hg from ASGM is entering both the terrestrial and aquatic ecosystems where it is converted in soils, sediment, and water to the neurotoxic and bioavailable form of MeHg.

Gerson, J.R., Driscoll, C.T., Hsu-Kim, H. and Bernhardt, E.S., 2018. Senegalese artisanal gold mining leads to elevated total mercury and methylmercury concentrations in soils, sediments, and rivers.  Elem Sci Anth, 6(1), p.11. DOI:

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In the place where you do research: What are childhood asthma rates?

Monday, July 29, 2019 - 6:49am

In a cross‐sectional study conducted in rural Senegal (Niakhar), Hooper et al. found that nearly one in ten children had symptoms suggestive of asthma; however, few children had a diagnosis of asthma or use appropriate therapies. More specifically, from a total of 1513 children aged 6‐7 years, 130 (9%) reported wheezing within the last 12months, and 41 (3%) had a clinical asthma diagnosis. 

Methodology: The researchers used the International Study of Asthma and Allergies in Childhood (ISAAC) survey instrument to assess childhood respiratory health in rural Senegal. They interviewed the caregivers of children aged 5 through 8 years of age in the four largest Niakhar villages in August 2012.

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