@article{PAR00004374,
  title = {{A}nomalous mercury isotopic compositions of fish and human hair in the {B}olivian {A}mazon},
  author = {{L}affont, {L}. and {S}onke, {J}.{E}. and {M}aurice, {L}aurence and {H}intelmann, {H}. and {P}ouilly, {M}arc and {B}acarreza, {Y}.{S}. and {P}erez, {T}. and {B}ehra, {P}.},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e report mercury ({H}g) mass-dependent isotope fractionation ({MDF}) and mass-independent isotope fractionation ({MIF}) in hair samples of the {B}olivian {E}sse {E}jjas native people and in several tropical fish species that constitute their daily diet {MDF} with delta {H}g-202 ranging from -0.40 to -0.92 parts per thousand for fish and +1.04 to +1.42 parts per thousand for hair was observed. {H}air samples of native people with a fish-dominated diet are enriched by +2.0 0.2 parts per thousand in 6212 {H}g relative to the fish consumed. {B}oth odd {H}g isotopes, {H}g-199 and {H}g-201, display {MIF} in fish (from -0.14 to +0.38 parts per thousand for {D}elta {H}g-201 and from -0.09 to +0.55 parts per thousand for {D}elta {H}g-199) and in hair (from +0.12 to +0.66 parts per thousand for {D}elta {H}g-201 and from +0.14 to +0.81 parts per thousand for {D}elta {H}g-199). {N}o significant difference in {MIF} anomalies is observed between {H}g in fish and in human hair, suggesting that the anomalies act as conservative source tracers between upper trophic levels of the tropical food chain, {F}ish {H}g {MIF} anomalies are 10-fold lower than those published for fish species from midlatitude lakes. {G}rouping all {A}mazonian fish species per location shows that {D}elta {H}g-199: {D}elta {H}g-201 regression slopes for the clear water {I}tenez {R}iver basin (0.95 +/- 0.08) are significantly lower than those for the white water {B}eni {R}iver basin (1.28 +/- 0.12). {A}ssuming that the observed {MIF} originates from aquatic photoreactions, we calculated limited photodemethylation of monomethylmercury ({MMH}g) in the {B}eni {R}iver floodplains and insignificant photodemethylation in the {I}tenez {R}iver floodplains. {T}his is possibly related to lower residence times of {MMH}g in the {I}tenez compared to the {B}eni {R}iver floodplains. {F}inally, a significantly negative {D}elta {H}g-201 of -0.14 parts per thousand in {B}eni {R}iver fish suggests that the inorganic {H}g precursor to the {MMH}g that bioaccumulates up the food chain defines an ecosystem specific non-zero {D}elta {H}g-201 baseline. {C}alculation of photodemethylation intensities from {H}g or {MMH}g {MIF}, therefore, requires a baseline correction.},
  keywords = {},
  booktitle = {},
  journal = {{E}nvironmental {S}cience and {T}echnology},
  volume = {43},
  numero = {23},
  pages = {8985--8990},
  ISSN = {0013-936{X}},
  year = {2009},
  DOI = {10.1021/es9019518},
  URL = {https://www.documentation.ird.fr/hor/{PAR}00004374},
}