# 87 (penta-CB) showed the highest concentration among the 19 PCBs congeners
Katsoyiannis and Samara  found that more than 50% of the total seven indicator PCB congeners
(PCB-28, 52, 101, 118, 138, 153, and 180) were absorbed in sludge and the concentration of the PCBs in wastewater was decreased from 1000 to 250ng/L after treatment (samples were from a WWTP in Thessaloniki, northern Greece).
Identification and quantification of 2,3,7,8-substituted congeners
of PCDDs D[Fs.sup.-1] and dioxin-like PCBs (non-and mono-ortho-substituted congeners
) was performed by using a (i) Shimadzu GC-14B gas chromatograph with AOC-1400 auto-sampler.
and Bemisia tabaci were obtained from stock colonies kept in a greenhouse at the Engineering Research Center of Biological Control, South China Agricultural University (SCAU) on poinsettia plants, Euphorbia pulcherrima Willd, which were grown in plastic pots (15 cm diameter).
The level of PCB congeners
found in milk samples are presented in Table I.
The list of congeners
, which includes acetaldehyde and a variety of esters (particularly the ethyl esters of [C.sub.8] to [C.sub.12] fatty acids), is extensive.
in alcohol may contribute to headaches, with red wine and other darker alcohols having the most effect.
(Fabaceae) as to provide evidence that competition for pollinators has influenced reproductive distinctions between the congeners
. The congeners
partially overlap in flowering period and share common pollinators.
The new information that now confirms the previously and apparently unknown or unreported presence of 2,3,7,8-TCDD on the site supports our belief that the concentrations of this congener
found in marine sediments near the plant outfall, and at a further site in Mississippi Sound, originated from the plant site.
Environmental "weathering", and bioaccumulation effects, dictate that polychlorinated biphenyls now be reported as congeners
, rather than as the original commercial mixes (e.g., Aroclor[R], Clophen, Kaneclor, Phenoclor).
A common application of this approach is when PCBs in environmental samples are identified by comparing the PCB congener
distribution pattern present in the samples with those obtained from commercial Aroclors.
PBDEs are molecules that can hold up to 10 bromine atoms in 209 different configurations, or congeners
. Commercial mixtures of PBDEs used as flame retardants are typically dominated by congeners
with a given number of bromines.