Research Article
Simultaneous Determination of Fluoroquinolones and
Sulfonamides Originating from Sewage Sludge Compost
K. Kipper,
1
M. Lillenberg,
2
K. Herodes,
1
L. Nei,
3
and E. Haiba
3
1
Institute of Chemistry, University of Tartu, Tartu, Estonia
2
Estonian University of Life Sciences, Tartu, Estonia
3
Tartu College, Tallinn University of Technology, Tartu, Estonia
Correspondence should be addressed to K. Kipper; karin.kipper@gmail.com
Received 20 February 2017; Revised 1 May 2017; Accepted 11 May 2017; Published 12 June 2017
Academic Editor: Sandra Babic
Copyright © 2017 K. Kipper et al. is is an open access article distributed under the Creative Commons Attribution License, which
permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
A simultaneous method for quantitative determination of traces of fluoroquinolones (FQs) and sulfonamides (SAs) in edible
plants fertilized with sewage sludge was developed. e compounds were extracted from the plants by rapid and simple liquid
extraction followed by extracts clean-up using solid phase extraction. e eluent additive 1,1,1,3,3,3-hexafluoro-2-propanol was
used for liquid chromatographic detection to achieve separation of structurally similar antimicrobials like ciprofloxacin and
norfloxacin. Identification and quantification of the compounds were performed using high-performance liquid chromatography
with electrospray ionization mass spectrometry in selected reaction monitoring mode. Method was validated and extraction
recoveries of FQs and SAs ranged from 66% to 93%. e limit of quantifications was from 5 ng/g in the case of ofloxacin to 40 ng/g
for norfloxacin. e method precision ranged from 1.43% to 2.61%. e developed novel method was used to evaluate the plats
antimicrobial uptake (potato (Solanum tuberosum L.), carrot (Daucus carota L.), lettuce (Lactuca sativa L.), and wheat (Triticum
vulgare L.)) from soil and migration of the analytes inside the plants.
1. Introduction
e increase of the yearly production of sewage sludge
compost containing human and veterinary antimicrobials
has led to antimicrobial resistance being one of the top health
challenges in the 21st century [1]. One of the largest and most
diverse microbial habitats on Earth is soil, a vast repository of
the antimicrobial resistance genes between soil bacteria and
clinical pathogens [2].
When antimicrobials are eliminated from the human
body, they can be excreted in their native form or as
metabolites [3]. Since antimicrobials are developed to have
a specific mode of action, even low levels of these drugs in
edible plants can cause effects in organisms [4].
Several studies have demonstrated that the two most
important sources through which toxic compounds reach the
environment are sewage sludge and compost, which are oſten
used in agriculture [5–9]. More generally, pharmaceuticals
move into the sewage system and to waste water treatment
plants [10]. e nutrition-rich sewage sludge and compost
can be used as fertilizers for plants. e increasing propor-
tions of administered drugs and personal care products are
alarming because the compound releases into the environ-
ment are not controlled [11, 12] and this is a potential threat to
the environment [13–15]. It is worrisome that pharmaceutical
compounds may potentially enter edible food plants that have
been fertilized with sewage sludge compost [9, 16–18].
e risks from the fertilizer should be evaluated carefully.
Exposure to pharmaceuticals via plant-derived foodstuffs is
usually low and effects on human health are in most cases
unlikely. is route of exposure may, however, be more
significant for a small number of highly toxic medicines or
in situations where long-term low-level exposure could elicit
subtler effects (e.g., promotion of antibacterial resistance or
endocrine disruption) [19]. A chemical can undergo various
structural changes by a multitude of biotic and nonbiotic pro-
cesses aſter its introduction into the environment. Structural
transformations may also be a result of effluent treatment
[4, 20–26]. e maximum residue levels (MRL) are set only
for food of animal origin, milk and meat [27, 28].
Hindawi
e Scientific World Journal
Volume 2017, Article ID 9254072, 8 pages
https://doi.org/10.1155/2017/9254072