Linked Life Data

15597892

Source:http://linkedlifedata.com/resource/pubmed/id/15597892

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
23
pubmed:dateCreated
2004-12-15
pubmed:abstractText
The effect of a mixture of 10 compounds, which have previously been identified in an effect-directed analysis as potentially relevant for a specific contaminated riverine sediment (Brack et al. Arch. Environ. Contam. Toxicol. 1999, 37, 164), were investigated for the underlying joint effect. Components identified in an organic sediment extract included several PAHs (benzo[ghi]fluoranthene, benz[a]anthracene, fluoranthene, pyrene, 2-phenylnaphthalene, anthracene, and phenanthrene) plus prometryn, N-phenyl-2-naphthylamine, and parathion-methyl. Experiments were performed using a one-generation algal bioassay with the unicellular green algae Scenedesmus vacuolatus as well as chlorophyll fluorescence quenching analysis to describe the effects of the components and mixtures thereof. Analysis of the mixture effects based on concentration-response modeling of the effect data reveals that indeed effect contributions of several components can be expected although the mixture ratio is not equitoxic and the individual components vary greatly with respect to biological effect. Comparing predicted and observed mixture effects, the combined effect may not be attributed to a joint narcotic effect of the mixture components. Evidently, some of the components act specifically and dissimilar and may therefore be best described in their combined effect by response addition while for others a similar mode of action seems plausible. Chlorophyll fluorescence quenching analysis supports to discriminate between prometryn, N-phenyl-2-naphthylamine, and PAHs. A joint model for calculating the combined effect using concentration addition for the suspected unspecifically acting components in algae (PAHs and parathion-methyl) and subsequently response addition for this group and the other components clearly improves the description of the observed combined effect. Allocation of effect contributions to specific components using toxic units or effect contributions lead to different judgments. The observed combined effect of a 3-compound mixture of prometryn, N-phenyl-2-naphthylamine, and benzo[ghi]fluoranthene is indistinguishable from the effects of the original 10-compound mixture, demonstrating the need in site-specific assessment of complex contamination to account for the mode of action of contaminants. Implications forthe confirmation step in effect-directed analysis of substances causing effects in complex contaminated samples are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0013-936X
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
38
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6353-62
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
What contributes to the combined effect of a complex mixture?
pubmed:affiliation
UFZ Centre for Environmental Research Leipzig Halle, Permoserstrasse 15, 04318 Leipzig, Germany. rolf.altenburger@ufz.de
pubmed:publicationType
Journal Article, Comparative Study