Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2008-9-8
pubmed:abstractText
The diffusion of drug residues in wastewaters and surface waters as rivers and streams may constitute a problem for the environment, with consequences on the ecosystem and also on the human health. This paper deals with the study of the photo-induced transformation of amiloride, an orally administered diuretic agent, under simulated solar light. Direct photolysis and photocatalyzed degradation processes, using titanium dioxide as a photocatalyst, were investigated. The study involved the monitoring of the drug decomposition, the identification of intermediate compounds of the decomposition, the assessment of mineralization, as well as the evaluation of the toxicity associated to the degradation products. Amiloride underwent complete degradation within 30min of irradiation (heterogeneous photocatalysis) or 4h (homogeneous photolysis). HPLC coupled to HRMS, via ESI interface, demonstrated to be a powerful tool to identify and measure degradation products of the studied drug. By considering the photocatalytic process, the identified intermediates are formed through: (1) dechlorination and hydroxylation of the heteroaromatic ring; (2) the detachment of the guanidinic moiety; (3) cleavage of the heteroaromatic ring. The drug photomineralization was a rather slow process and after 4h of irradiation 25% of the total organic carbon (TOC) was still present. Chlorine was stoichiometrically released as chloride ions within the considered irradiation times (4h), while nitrogen was only partially converted into ammonium ions. This was due to the formation of guanidine, known to be hardly mineralized photocatalytically, and some other small molecules still containing the nitrogen. Acute toxicity, measured with a Vibrio fischery assay, showed that amiloride transformation proceeded through the formation of toxic compounds.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0731-7085
pubmed:author
pubmed:issnType
Print
pubmed:day
29
pubmed:volume
48
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
315-20
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Study of the photolytic and photocatalytic transformation of amiloride in water.
pubmed:affiliation
Department of Analytical Chemistry, University of Turin, via P. Giuria 5, 10125 Torino, Italy. paola.calza@unito.it
pubmed:publicationType
Journal Article