Interindividual differences in o,p'-DDD enantiomer kinetics examined in Göttingen minipigs

• Five minipigs were given a single oral dose of a racemic mixture of o,p’-DDD (30 mg kg-1 b.w., EF = 0.49). Blood plasma and subcutaneous adipose tissue were collected for analysis, at different time-points over 180 d. At the end of the experiment also liver, kidney and brain tissue were collected. Low concentrations of o,p’-DDD still remained after 180 d in plasma (mean 0.5 ±0.3 ng g-1 f.w.) and in adipose tissue (mean 40 ±40 ng g-1 f..w.). The mean concentrations in liver and kidney were 500 ±300 pg g-1 f.w. and 90 ±50 pg g-1 f.w. respectively. The enantiomers of o,p’-DDD were isolated by HPLC and the absolute configuration of the enantiomers were determined by X-ray crystallography and polarimetry as R-(+)-o,p’-DDD and S-(-)-o,p’-DDD. The enantiomer fractions (EFs) of o,p’-DDD were determined in plasma, adipose tissue and kidney using GC/ECD equipped with a chiral column. The EFs of o,p’-DDD in the individual minipigs showed large variability, ranging from 0.2-0.6 after 24 h in plasma and from 0.2-0.7 after 90 d in adipose tissue. Hence in two of the minipigs, the S-(-)-o,p’-DDD enantiomer was dominating while the other enantiomer, R-(+)-o,p’-DDD was dominating in three minipigs. We propose that a yet not identified factor related to polymorphism, regulating the metabolism and/or elimination of the enantiomeric o,p´-DDD, is responsible for the differences in enantiomeric retention of the compound in the minipigs.

Ämnesord

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Miljövetenskap (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Environmental Sciences (hsv//eng)

Nyckelord

Chiral analysis

enantioselective toxicokinetics

adrenocortical carcinoma

enantiomer fraction

absolute configuration

Environmental chemistry

Miljökemi

miljökemi

Environmental Chemistry

Publikations- och innehållstyp

pop (ämneskategori)

ovr (ämneskategori)