Linked Life Data

19388791

Source:http://linkedlifedata.com/resource/pubmed/id/19388791

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2009-11-24
pubmed:abstractText
Knowledge gaps in nanomaterial fate and toxicity currently limit the ability of risk assessments to characterize the environmental implications of nanomaterials. This problem is further complicated by the lack of standardized characterization and preparation methodologies for researchers to gain the needed information to assist risk assessors. In the present study, data were generated to determine if multiwalled nanotube (MWNT) fate and toxicity are altered by engineered surface modifications or by different dispersal methods. While dissolved organic matter was a good dispersing agent of MWNTs in water, the humic acid fraction was a more effective dispersant than the fulvic acid fraction. When stabilized in organic matter, the functional group attached to the MWNT controlled its toxicity. Underivatized MWNTs induced relatively moderate toxicity to Ceriodaphnia dubia after 96 h (25 +/- 19% survival at 26 mg/L), while hydrophilic groups (hydroxyl, carboxyl) reduced this toxicity (93 +/- 12% survival at 48 mg/L). However, other functional groups (alkyl, amine) increased toxicity (0 +/- 0% survival at <15 mg/L). In dispersal method studies, sonication of MWNTs increased fragmentation relative to magnetic stirring. The sonication treatment of MWNTs also slightly reduced the mortality of C. dubia in the water column but increased toxicity in the sediment to Leptocheirus plumulosus and Hyalella azteca. Findings in the present study indicate that nanotubes engineered for specific applications need to be managed independently and that laboratory methods to disperse and test nanotubes in bioassays need to be standardized to obtain repeatable results for comparison of materials.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0730-7268
pubmed:author
pubmed:issnType
Print
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1930-8
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Influence of nanotube preparation in aquatic bioassays.
pubmed:affiliation
US Army Engineer Research and Development Center, Environmental Laboratory, Vicksburg, Mississippi 39180, USA. alan.j.kennedy@usace.army.mil
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.