6 research outputs found
Human mercury exposure associated with small-scale gold mining in Burkina Faso.
PURPOSE: In Burkina Faso, gold ore is one of the main sources of income for an important part of the active population. Artisan gold miners use mercury in the extraction, a toxic metal whose human health risks are well known. The aim of the present study was to assess mercury exposure as well as to understand the exposure determinants of gold miners in Burkinabe small-scale mines.METHODS: The examined gold miners' population on the different selected gold mining sites was composed by persons who were directly and indirectly related to gold mining activities. But measurement of urinary mercury was performed on workers most susceptible to be exposed to mercury. Thus, occupational exposure to mercury was evaluated among ninety-three workers belonging to eight different gold mining sites spread in six regions of Burkina Faso. Among others, work-related exposure determinants were taken into account for each person during urine sampling as for example amalgamating or heating mercury. All participants were medically examined by a local medical team in order to identify possible symptoms related to the toxic effect of mercury.RESULTS: Mercury levels were high, showing that 69% of the measurements exceeded the ACGIH (American Conference of Industrial Hygienists) biological exposure indice (BEI) of 35 µg per g of creatinine (µg/g-Cr) (prior to shift) while 16% even exceeded 350 µg/g-Cr. Basically, unspecific but also specific symptoms related to mercury toxicity could be underlined among the persons who were directly related to gold mining activities. Only one-third among the studied subpopulation reported about less than three symptoms possibly associated to mercury exposure and nearly half of them suffered from at least five of these symptoms. Ore washers were more involved in the direct handling of mercury while gold dealers in the final gold recovery activities. These differences may explain the overexposure observed in gold dealers and indicate that the refining process is the major source of exposure.CONCLUSIONS: This study attests that mercury exposure still is an issue of concern. North-South collaborations should encourage knowledge exchange between developing and developed countries, for a cleaner artisanal gold mining process and thus for reducing human health and environmental hazards due to mercury use
Antimicrobial Activities of Methanol, Ethanol and Supercritical CO2 Extracts of Philippine Piper betle L. on Clinical Isolates of Gram Positive and Gram Negative Bacteria with Transferable Multiple Drug Resistance
Assessing the ecotoxicity of gold mine tailings utilizing earthworm and microbial assays
Problems associated with mining are the disposal
of wastes on tailing disposal facilities (TDFs). The
aim of this study was to determine the ecotoxicity of
gold mine tailings by using earthworm bioassays, earthworm
biomarkers and enzymatic analyses. End points
included changes in biomass, reproduction, lysosomal
membrane stability, tissue metal concentrations, and
selected enzymatic activities. Results indicated high
concentrations of Ni in the material as well as bioaccumulation
of lead and arsenic in the earthworm body
tissue after exposure. Enzymatic activity was higher in
revegetated tailings than in unrehabilitated tailings. It
was concluded that TDF and surrounding areas have an
acidic pH which affects earthworms and metal bioavailability.
Soil enzymatic activities were a sensitive indicator
of metal pollution in mining areas. Growth, reproduction
and lysosomal membrane stability of earthworms
have also been shown to be sensitive end points
to assess the ecotoxic effects of gold TD