Chiral profiling of azole antifungals in municipal wastewater and recipient rivers of the Pearl River Delta, China

Abstract

Enantiomeric compositions and fractions (EFs) of three chiral imidazole (econazole, ketoconazole, and miconazole) and one chiral triazole (tebuconazole) antifungals were investigated in wastewater, river water, and bed sediment of the Pearl River Delta, South China. The imidazole pharmaceuticals in the untreated wastewater were racemic to weakly nonracemic (EFs of 0.450-0.530) and showed weak enantioselectivity during treatment in the sewage treatment plant. The EFs of the dissolved azole antifungals were usually different from those of the sorbed azoles in the suspended particulate matter, suggesting different behaviors for the enantiomers of the chiral azole antifungals in the dissolved and particulate phases of the wastewater. The azole antifungals were widely present in the rivers. The bed sediment was a sink for the imidazole antifungals. The imidazoles were prevalently racemic, whereas tebuconazole was widely nonracemic in the rivers. Seasonal effects were observed on distribution and chirality of the azole antifungals. Concentrations of the azole antifungals in the river water were relatively higher in winter than in spring and summer while the EF of miconazole in the river water was higher in summer. The mechanism of enantiomeric behavior of the chiral azole antifungals in the environment warrants further research.

Occurrence and ecological potential of pharmaceuticals and personal care products in groundwater and reservoirs in the vicinity of municipal landfills in China

“…The other azole anti-fungals were all only occasionally detected and at very low concentrations (Table 1). This pattern was similar to that in the water of the Pearl River (Huang et al, 2013). However, the presence of the azole anti-fungals in groundwater has rarely been reported worldwide, precluding further discussion or comparison (Table 1).…”

“…Box-and-whisker plots of the PPCPs in the reservoirs in the vicinity of the landfills. See Table 1 also revealed higher PPCP concentrations in wintertime in the Pearl River and suggested that dilution effects play a predominant role in seasonal PPCP patterns in river water (Huang et al, , 2013Peng et al, 2011). However, limited sampling sites in the reservoirs precluded indepth analysis of seasonal effects on the distribution of PPCPs in the reservoirs.…”

Occurrence of Chiral Bioactive Compounds in the Aquatic Environment: A Review

“…GC-MS/MS was employed in the first works reporting enantioselective environmental analysis by indirect methods using enantiomerically-pure derivatizing reagents [9,60], or by direct methods using CSPs [61,85]. Despite indirect [70,83] and direct methods [67,80,89] remaining in some studies, LC-MS/MS has been the analytical technique of election for illicit drugs and pharmaceutical while GC-MS and GC-ECD have been the most used for pesticides [13,54,55,57,62,[64][65][66][67][68][69][71][72][73][74][75][76][77][80][81][82]84,87,88,[90][91][92]95,[100][101][102][103][104][105]. Although much less used, LC-DAD, LC-UV and LC-FD detection have been used in some of the studies [11,26,27,…”

“…A study focused in the enantioselective determination of azole antifungals showed that these pharmaceuticals were racemic or almost racemic in the raw wastewater (EFs = 0.45-0.53) and a weak enantioselectivity was observed during treatment at WWTP [88]. The EFs of the dissolved antifungals differed from those of the sorbed fraction in the suspended particulate matter, proposing different behaviors for these enantiomers in the two distinct phases of the wastewater.…”

Chiral Pharmaceuticals in Diverse Environmental Matrices: Occurrence, Removal and Toxicity

“…O mesmo grupo de investigadores estudou os mesmos antifúngicos quirais (excepto propiconazol) em águas residuais e superficiais. 117 Neste estudo, a FE nos afluentes foi globalmente de 0,5, não variando significativamente após tratamento na ETE, mesmo quando as concentrações diminuíram muito, sugerindo uma degradação fracamente enantiosseletiva. Pelo contrário, na matéria particulada das águas residuais, a FE dos antifúngicos foi ligeiramente diferente de 0,5 no afluente e 0,5 após tratamento anaeróbio, sem variação da concentração.…”