Lecture: Monitoring of Selected Pollutants and Metabolites of Pharmaceuticals in Fish (dissertation
thesis defence)

Ph.D. adept: Samuel Mach, supervisor: Assoc. Prof. RNDr. Zdeněk Šimek, Ph.D.,
special consultant: RNDr. Alexandr Jegorov, Ph.D. (Teva Czech Industries, s.r.o.)

Abstract: The aim of this thesis is to bring new insight in the field of exposition of fish to
xenobiotics released by humans. Two different perspectives were used:

1. Monitoring of one special group of contaminants, hexabromocyclododecane (HBCD) predominant
isomers, in fish obtained from polish fish market. A suitable analytical method including sample
preparation, instrumental analysis (HPLC/MS) and quality assurance and controll was adjusted.
Relationship among individual HBCD isomers and their concantrations in fish and relationship
between level of total HBCD content and lipid content were discussed.

2. Monitoring of metabolites of 2 APIs (active pharmaceutical ingredients) formed
in laboratory conditions in model fish species, Ameiurus Nebulosus. Both APIs, obeticholic acid
(OCA) and abirateron acetate (ABR-acetate), have steroid skeleton. OCA, in addition, is by nature a
synthetic derivative of a naturally occuring bile acid (6-alpha-ethyl-derivative
of chenodeoxycholic acid). This monitoring contributed to understanding of metabolism pathways of
these special APIs in fish. Comparison with metabolism of these APIs in humans and other mammals
and with metabolism of other steroids in fish was discussed, in case of OCA also comparison with
metabolism of naturally occuring bile acids both in humans and other mammals and fish.