Dietary Bioavailability of Cu Adsorbed to Colloidal Hydrous Ferric Oxide

作者：Cain Daniel J^*; Croteau Marie Noele; Fuller Christopher C

来源：Environmental Science & Technology, 2013, 47(6): 2869-2876.

DOI：10.1021/es3044856

The dietary bioavailability of copper (Cu) adsorbed to synthetic colloidal hydrous ferric oxide (HFO) was evaluated from the assimilation of Cu-65 by two benthic grazers, a gastropod and a larval mayfly. HFO was synthesized, labeled with Cu-65 to achieve a Cu/Fe ratio comparable to that determined in naturally formed HFO, and then aged. The labeled colloids were mixed with a food source (the diatom Nitzschia palea) to yield dietary Cu-65 concentrations ranging from 211 to 2204 nmol/g (dry weight). Animals were pulse fed the contaminated diet and assimilation of Cu-65 from HFO was determined following 1-3 days of depuration. Mass transfer of Cu-65 from HFO to the diatom was less than 1%, indicating that HFO was the source of Cu-65 to the grazers. Estimates of assimilation efficiency indicated that the majority of Cu ingested as HFO was assimilated (values >70%), implying that colloidal HFO potentially represents a source of dietary Cu to benthic grazers, especially where there is active formation and infiltration of these particles into benthic substrates.

• 出版日期2013-3-19