Prevalence of per- and polyfluoroalkyl substances (PFASs) in drinking and source water from two Asian countries.

The present study focuses on the determination of the occurrence and levels of per- and polyfluoroalkyl substances (PFASs) in the drinking and source water from the Philippines and Thailand. A total of 46 samples (18 commercial bottled waters, 5 drinking water from vending machine (re-fill stations) and 23 source water) were analyzed using liquid chromatography with tandem high-resolution mass spectrometry. Using the targeted method, 12 different PFASs were detected in the drinking water samples with total quantifiable PFASs (∑PFASs) levels ranging from 7.16 to 59.49 ng/L; 15 PFASs were detected in source water with ∑PFASs ranging from 15.55 to 65.65 ng/L. A 100% detection frequency was observed for perfluoroheptanoic acid (PFHpA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorosulfonic acid (PFOS) in all water samples. Six other PFASs, not included in the targeted analysis, were detected using the suspect screening approach. For the first time, the presence of 2-(N-methylperfluorooctanesulfonamido) acetic acid (N-MeFOSAA) in drinking water is reported, and 3 novel PFASs (C5H5OF8, C6H4O2F6, and C9H2O2F16) were detected using suspect screening in source water. Combined results from target and suspect screening analysis showed that PFASs detected were predominantly (52%) short-chain (with fluorinated alkyl chain of ≤6) which could be explained by their high mobility in the environment. The detected PFASs levels in drinking water will not likely pose immediate health risk to consumers according to US EPA health advisory for PFOS and PFOA of 70 ng/L, but inclusion of bottled and drinking water from re-fill stations in monitoring programs is warranted.

Selective Uptake and Bioaccumulation of Antidepressants in Fish from Effluent-Impacted Niagara River.

The continuous release of pharmaceuticals and personal care products (PPCPs) into freshwater systems impacts the health of aquatic organisms. This study evaluates the concentrations and bioaccumulation of PPCPs and the selective uptake of antidepressants in fish from the Niagara River, which connects two of the North American Great lakes (Erie and Ontario). The Niagara River receives PPCPs from different wastewater treatment plants (WWTPs) situated along the river and Lake Erie. Of the 22 targeted PPCPs, 11 were found at part-per-billion levels in WWTP effluents and at part-per-trillion levels in river water samples. The major pollutants observed were the antidepressants (citalopram, paroxetine, sertraline, venlafaxine, and bupropion, and their metabolites norfluoxetine and norsertraline) and the antihistamine diphenhydramine. These PPCPs accumulate in various fish organs, with norsertraline exhibiting the highest bioaccumulation factor (up to about 3000) in the liver of rudd (Scardinius erythrophthalmus), which is an invasive species to the Great Lakes. The antidepressants were selectively taken up by various fish species at different trophic levels, and were further metabolized once inside the organism. The highest bioaccumulation was found in the brain, followed by liver, muscle, and gonads, and can be attributed to direct exposure to WWTP effluent.

Dispersive solid-phase extraction using polyaniline-modified zeolite NaY as a new sorbent for multiresidue analysis of pesticides in food and environmental samples.

The applicability of polyaniline (PANI)-modified zeolite NaY as a sorbent for multi-class pesticides extraction was investigated. The sorbent had a sorption capacity of 833mgkg-1 sorbent and preconcentration factor of 42 in the mixture of twenty pesticides. The PANI-coated zeolite NaY was successfully created via oxidative polymerization of aniline onto the surface of the zeolite. The sorbent was applied for dispersive solid phase extraction (DSPE) of commonly used pesticides belonging to five different chemical groups, involving carbamate, organophosphate, sulfonylurea, pyrethroid and neonicotinoid. The coupling of DSPE and HPLC-PDA resulted in an efficient method for multiresidue analysis of pesticides. The proposed method gave LODs and LOQs in the ranges of 0.001-1.00mgL-1 and 0.005-2.50mgL-1, respectively. The method was applied for determination of pesticide residues in environmental and food samples including drinking water, pond waters, soils, honey, cabbages, cucumbers, tomatoes and strawberries which were collected in Khon Kaen Province, Thailand. Recoveries of the target pesticides were in the range of 64-128% with RSDs less than 12% using matrix matched calibration for all sample matrices. Eight pesticides were found in fruit and vegetable samples at concentrations of 0.003-0.033mgkg-1 whereas a few compounds in contaminated pond waters have concentrations of 0.046-0.092mgL-1. The occurrence of high concentration of up to 1.26mgkg-1 in the soil samples is noteworthy.

Vortex-Assisted Dispersive Micro-Solid Phase Extraction Using CTAB-Modified Zeolite NaY Sorbent Coupled with HPLC for the Determination of Carbamate Insecticides.

A vortex-assisted dispersive micro-solid phase extraction (VA-D-µ-SPE) based on cetyltrimethylammonium bromide (CTAB)-modified zeolite NaY was developed for preconcentration of carbamate pesticides in fruits, vegetables, and natural surface water prior to analysis by high performance liquid chromatography with photodiode array detection. The small amounts of solid sorbent were dispersed in a sample solution, and extraction occurred by adsorption in a short time, which was accelerated by vortex agitation. Finally, the sorbents were filtered from the solution, and the analytes were subsequently desorbed using an appropriate solvent. Parameters affecting the VA-D-µ-SPE performance including sorbent amount, sample volume, desorption solvent ,and vortex time were optimized. Under the optimum condition, linear dynamic ranges were achieved between 0.004-24.000 mg kg(-1) (R(2) > 0.9946). The limits of detection (LODs) ranged from 0.004-4.000 mg kg(-1). The applicability of the developed procedure was successfully evaluated by the determination of the carbamate residues in fruits (dragon fruit, rambutan, and watermelon), vegetables (cabbage, cauliflower, and cucumber), and natural surface water.