Study: Female gold diggers at risk of passing mercury to unborn babies

Women in gold mining sites in Migori County are exposed to high levels of mercury that could harm them and their unborn babies.

A global study found nearly half of Kenyan women involved in artisanal and small-scale gold mining (ASGM) had mercury levels that exceeded 1 ppm, which approximately corresponds to the US Environmental Protection Agency reference dose.

Mercury levels above 1ppm can be linked to brain damage, IQ loss, and kidney and heart damage.

But foetal neurological damage can begin at mercury levels greater than 0.58ppm for which an even higher percentage (71 per cent) of Kenyan women involved in the study were found to be exposed to.

Women in gold mines in Osiri, Mikei, and Masara in Migori were among 1,044 women of child-bearing age who gave samples in 37 locations across 25 countries.

"Sampling results from women directly engaged in ASGM, or who had family members practicing ASGM with mercury in Indonesia, Kenya, and Myanmar show significantly elevated mercury levels in their hair," states the report made public last month.

"In Kenya and Myanmar, the percentage of women exceeding the 1 ppm threshold level was 44 per cent – 93 per cent respectively. When compared to the 0.58 ppm threshold level, the percentage rose to 71 per cent and 100 per cent respectively," adds the report.

The survey was done by IPEN - a network of non-governmental organisations working in more than 100 countries to reduce and eliminate the harm to human health and the environment from toxic chemicals.

In ASGM, elemental mercury is often used to amalgamate gold dust obtained by low technology mining (panning, sluicing, and ball milling).

The gold and mercury amalgam is ‘roasted’, often in domestic settings, to vaporise the mercury, leaving a small amount of gold.

MERCURY EXPOSURE

This leads to direct mercury exposure through handling and fume inhalation.

"The results from this study strongly suggest that the practice of artisanal and small-scale gold mining (ASGM) using mercury leads to elevated mercury levels for women engaged in this activity," the report states.

"Urgent action must be taken to reduce and eliminate mercury exposure of women involved in ASGM activity. An outright ban on mercury use in ASGM and the trade in mercury associated with it would have the most immediate beneficial health impacts for women," the report recommends. 

"In the absence of urgent action, generations of women and their offspring will bear the brunt of mercury contamination, while others will profit from ongoing mercury pollution," it warns.

Other factors that resulted in elevated levels of mercury in mothers and potential mothers across different countries and continents were a fish-rich diet and proximity to industrial locations. 

The report cautions that mercury pollution poses a serious and substantial threat to the health of women and the developing fetus in many parts of the world.

Of the 1,044 women who participated in the study, 42 per cent had a mercury body burden that exceeded the reference level of 1ppm total mercury in hair.

Locations where the mean (average) level for the group of women exceeded the 1ppm reference level for mercury were the Cook Islands, Indonesia, Kenya, Kiribati, Marshall Islands, Myanmar, Nepal (location A), Nigeria, Solomon Islands, Thailand, Tonga, and Tuvalu.

A second tier of women from Alaska, Albania, Chile, Kazakhstan (location B), Ukraine, and Vanuatu exceeded the 0.58 ppm mercury level as the mean for the group. 

“This study illustrates the unfolding global mercury pollution threat for the women and children of many Pacific Island nations and for most women engaged in small-scale gold mining,” said Lee Bell, policy mercury adviser.

But the study reveals that more women from the Osiri and Mikei locations had elevated levels of mercury than in the Masara location even as all locations reported significant elevated levels.

The study is the first of its kind to sample as many countries and regions and spotlight women of childbearing age.