| dc.creator |
Ikingura, Justinian R. |
|
| dc.creator |
Akagi, Hirokatsu |
|
| dc.date |
2016-06-13T06:07:01Z |
|
| dc.date |
2016-06-13T06:07:01Z |
|
| dc.date |
1999 |
|
| dc.date.accessioned |
2018-03-27T08:57:26Z |
|
| dc.date.available |
2018-03-27T08:57:26Z |
|
| dc.identifier |
Ikingura, J.R. and Akagi, H., 1999. Methylmercury production and distribution in aquatic systems. Science of the Total Environment, 234(1), pp.109-118. |
|
| dc.identifier |
http://hdl.handle.net/20.500.11810/2439 |
|
| dc.identifier |
10.1016/S0048-9697(99)00116-3 |
|
| dc.identifier.uri |
http://hdl.handle.net/20.500.11810/2439 |
|
| dc.description |
Mercury methylation and partitioning between sediment, water and fish were studied in river sediment spiked with
mercuric chloride at levels of 1, 5 and 10 ppm as Hg. Maximum methylmercury production in the sediment occurred
during the first week of incubation, with concentrations reaching 45.5 ngrg dry wt. . Equilibrium conditions were Ž .
established 3]4 weeks after the contamination of the sediment with mercury. Methylmercury partitioning between
sediment and water yielded methylmercury levels of 25]154 ngrl in the fish aquariums and 0.26 ngrl in the fish-free
control after 1 week of incubation. Equilibrium levels were 1.5]5.5 ngrl and 0.53 ngrl, respectively, during the 7th
week. Over 50% of the methylmercury in whole water were in soluble form or associated with colloidal particulate
-1 mm. Mercury concentration in fish increased almost exponentially from 30 ppb to an average of 345 ppb within 3
weeks. Mercury uptake rates by fish were in the range of 10]18 ngrg per day during the 2nd and 3rd weeks, high
rates occurring in water with methylmercury to total mercury ratios )0.45. The partition coefficients for total
mercury and methylmercury between fish and water Ž . K were 5000]7000 and 10 000]22 000, respectively. Large f ] w
differences were observed in methylmercury production in sediment]water incubation with fish and the fish-free
control. Equilibrium methylmercury concentrations in sediment were in the range 15]32 ngrg in the aquariums
containing fish and 3]4.5 ngrg in the fish-free control. The significance of fish in mercury methylation in the
aquariums still remains to be clarified as fish itself cannot methylate mercury in vivo. |
|
| dc.language |
en |
|
| dc.publisher |
Elsevier |
|
| dc.subject |
Mercury |
|
| dc.subject |
River sediment |
|
| dc.subject |
Methylation |
|
| dc.subject |
Partitioning |
|
| dc.subject |
Fish |
|
| dc.title |
Methylmercury Production and Distribution in Aquatic Systems |
|
| dc.type |
Journal Article, Peer Reviewed |
|