Page 192 - Materials Chemistry, Second Edition

Determination of Pharmaceutical Compounds in Sewage Sludge 173

(alprenolol, norephedrine, and tramadol) significantly deviated from the racemic
proportion. This fact was explained by biological processes occurring during acti-
vated sludge treatment or during anaerobic digestion.
A wide range of concentration levels have been reported for pharmaceutical com-
pounds in sewage sludge. Verlicchi and Zambello (2015), in a review of 59 papers
about the presence of 152 pharmaceuticals in different types of sewage sludge,
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reported that analgesics are in the range of 3–10,000 ng g d.m. in primary sludge,
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1–1000 ng g d.m. in secondary sludge, 4–1000 ng g d.m. in digested sludge, and
10–1000 ng g d.m in compost; antibiotics are in the range of 5–4000 ng g d.m.
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in primary sludge, 0.1–70,000 ng g d.m. in secondary sludge, 1–8000 ng g d.m.

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in digested sludge, and 0.8–200 ng g d.m in compost; hormones are in the range
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of 4–400 ng g d.m. in primary sludge, 0.1–300 ng g d.m. in secondary sludge,

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1–10,000ng g d.m. in digested sludge, and 20–200 ng g d.m in compost; and psy-
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chiatric drugs are in the range of 5–2000 ng g d.m. in primary sludge, 1–600 ng g
d.m. in secondary sludge, 0.1–3000ng g d.m. in digested sludge, and 0.1–900 ng g

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d.m in compost.
To obtain information about the occurrence and fate of pharmaceutical com-
pounds and their metabolites in sewage sludge, accurate and sensitive methods are
needed. In this chapter, an overview of extraction and detection techniques applied
to the determination of pharmaceutical compounds in sewage sludge from urban
WWTPs is discussed. The application of analytical methodologies to obtain infor-
mation about the evolution of their concentration in the sludge treatment line, their
occurrence and fate in sewage sludge from different treatment technologies, and
the ecotoxicological risk assessment of sewage sludge application to soils are also
described.
9.2 METHODOLOGY FOR THE DETERMINATION OF
PHARMACEUTICALS IN SEWAGE SLUDGE
The occurrence and fate of pharmaceutical compounds in sewage sludge have not
been studied in such depth as has been done in wastewater. This fact can be explained
by the difficulties of detecting and quantifying such low trace pollutants in the com-
plex sludge matrix. The following section discusses the main extraction and deter-
mination techniques reported for the determination of pharmaceutical compounds in
sewage sludge from urban WWTPs. An overview of analytical methods reported for
the determination of pharmaceuticals in sewage sludge is shown in Table 9.1.
9.2.1 saMple TreaTMenT
The main goals of sludge sample treatment are to achieve good extraction recover-
ies for the target compounds, reducing interfering compounds to the lowest levels,
which can involve a difficult and time-consuming step (Peysson and Vulliet, 2013).
Moreover, after sample extraction, a clean-up step can still be required to reduce inter-
fering compounds before analytical determination. Extraction methods should be
simple and easy to perform, should require small volumes of organic solvents, should
generate little waste, and should require cheap equipment to make the methodology