Residue Analysis and Risk Assessment of Oxathiapiprolin and Its Metabolites in Cucumbers under Field Conditions.

In this study, a rapid, sensitive, and selective method was established for the detection of oxathiapiprolin and the metabolite IN-E8S72, as well as its glucose conjugate IN-SXS67 in cucumber using modified QuEChERS procedure combined with HPLC-MS/MS. The LOQs for all compounds were 0.02 mg kg-1, and the average recoveries were 77.4-111.3% with RSDs of 1.0-8.5%. Under the optimized conditions, the established method was successfully used to determine field samples in dissipation and terminal residue studies. The dissipation study results showed that oxathiapiprolin dissipated rapidly in cucumber with half-lives of 2.4-4.0 days. On the basis of the terminal residue results, the risk assessment was conducted, and both the international estimated daily intake (IEDI) or national estimated daily intake (NEDI) of oxathiapiprolin were much less than 100% which indicate a low health risk to consumers. This work provides guidance for establishing MRL of oxathiapiprolin in China and is of great significance for evaluating its dietary risk in cucumber.

Aquatic hazard, bioaccumulation and screening risk assessment for ammonium 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)-propanoate.

The fluoropolymer manufacturing industry is moving to alternative polymerization processing aid technologies with more favorable toxicological and environmental profiles as part of a commitment to curtail the use of long-chain perfluoroalkyl acids (PFAAs). To facilitate the environmental product stewardship assessment and premanufacture notification (PMN) process for a candidate replacement chemical, we conducted acute and chronic aquatic toxicity tests to evaluate the toxicity of ammonium 2,3,3,3-tetrafluoro-2-(heptafluoropropoxy)-propanoate (C6HF11O3.H3N) or the acid form of the substance to the cladoceran, Daphnia magna, the green alga, Pseudokirchneriella subcapitata, and a number of freshwater fish species including the rainbow trout, Oncorhynchus mykiss, In addition, testing with the common carp, Cyprinus carpio, was conducted to determine the bioconcentration potential of the acid form of the compound. Based on the relevant criteria in current regulatory frameworks, the results of the aquatic toxicity and bioconcentration studies indicate the substance is of low concern for aquatic hazard and bioconcentration in aquatic organisms. Evaluation of environmental monitoring data in conjunction with the predicted no effect concentration (PNEC) based on the available data suggest low risk to aquatic organisms.

Simultaneous determination of oxathiapiprolin and two metabolites in fruits, vegetables and cereal using a modified quick, easy, cheap, effective, rugged, and safe method and liquid chromatography coupled to tandem mass spectrometry.

An effective and rapid analytical method for the simultaneous determination of a new fungicide oxathiapiprolin and its metabolites (IN-E8S72 and IN-WR791) residues in fruits (grape, watermelon, watermelon peel), vegetables (cucumber, tomato, potato) and cereal (wheat) was developed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) using the modified quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction concept. Three target compounds were extracted from all matrices with 1% (V/V) formic acid aqueous solution and acetonitrile then cleaned by dispersive solid phase extraction (dSPE) with octadecylsilane (C18) and graphitized carbon black (GCB). The determination of the target compounds was achieved within a 5.1min run time by using an UPLC HSS T3 column connected to an electrospray ionization source (ESI, positive ion mode) for oxathiapiprolin and the negative mode for the two metabolites. The method showed excellent linearity (R(2)>0.9904) for target compounds. The limit of detection (LOD) for the three compounds ranged from 0.5µgkg(-1) to 7.5µgkg(-1) and the limits of quantitation (LOQ) were 1µgkg(-1) and 10µgkg(-1) for oxathiapiprolin and the metabolites, respectively. The mean recoveries from seven matrices ranged from 81.5 to 110.7%, with intra-day relative standard deviations (RSDr) in the range of 0.8-12.0% for all three test compounds. The inter-day RSDR were less than 14.5% for all of the recovery tests. The method was successfully applied for simultaneous analysis of oxathiapiprolin and its metabolites in actual trial samples, indicating its effectiveness in investigating oxathiapiprolin and its metabolites in the food.

Prospective, open-label assessment of albuterol sulfate hydrofluoroalkane metered-dose inhaler with new integrated dose counter.

Metered-dose inhalers (MDIs) allow patients who require therapy for various respiratory diseases to deliver these therapies directly to the airways via inhalation. MDIs are designed to contain more propellant than required for administration of the labeled number of actuations; therefore, the amount of active medication/actuation remaining after administration of the labeled number of actuations may result in a lower than therapeutic dose of active medication. An MDI with an integrated dose counter provides the only reliable means by which a patient can track the amount of medication remaining in the MDI. This study evaluated the functionality, reliability, accuracy, and patient satisfaction with albuterol sulfate hydrofluoroalkane (HFA) MDI with a new integrated dose counter in the clinical setting. Patients aged ≥4 years with asthma, chronic obstructive pulmonary disease, or both, participated in this phase 4, prospective, open-label study. Treatment was twice-daily dosing with albuterol HFA MDI at 90 micrograms with dose counter for either 5 or 7 weeks. Concordance/agreement between daily patient recordings of actuations and counter readings was assessed with five discrepancy types: fire not count (undercount; primary end point), count not fire (overcount), fire count up within a dose (counter reading increased, instead of decreased, after MDI was actuated), count unknown fire (counter number at the beginning of a dosing session was less than counter number at the end of the previous session), and count up unknown fire (counter number at the beginning of a dosing session was greater than counter number at the end of the previous session). Responses to twelve questions designed to evaluate confidence, ease of use, and patient satisfaction were also analyzed. Overall discrepancy rate was 1.87 per 200 actuations. Primary end point (fire not count rate) was 0.30 per 200 actuations. Overall, ~95-97% of patients were "very satisfied" or "somewhat satisfied" with the albuterol HFA MDI with dose counter, its ease of use, and the ability to tell when it should be replaced. The albuterol HFA MDI with new integrated dose counter functioned reliably and accurately in the clinical setting. Overall patient satisfaction was high with the albuterol HFA MDI with new integrated dose counter and the device was shown to function reliably and accurately. Clinicaltrials.gov identifier: NCT01302587.

Compound A uptake and metabolism to mercapturic acids and 3,3,3-trifluoro-2-fluoromethoxypropanoic acid during low-flow sevoflurane anesthesia: biomarkers for exposure, risk assessment, and interspecies comparison.

BACKGROUND: Sevoflurane is degraded during low-flow anesthesia to fluoromethyl-2,2-difluoro-1-(trifluoromethyl)vinyl ether ("compound A"), which causes renal necrosis in rats but is not known to cause nephrotoxicity in surgical patients. Compound A is metabolized to glutathione S-conjugates and then to cysteine S-conjugates, which are N-acetylated to mercapturic acids (detoxication pathway), or metabolized by renal beta-lyase to reactive intermediates (toxification pathway) and excreted as 3,3,3-trifluoro-2-fluoromethoxypropanoic acid. This investigation quantified compound A metabolites in urine after low-flow sevoflurane administration, to assess relative flux via these two pathways. METHODS: Patients (n = 21) with normal renal function underwent low-flow (11 min) sevoflurane anesthesia designed to maximize compound A formation. Inspiratory, expiratory, and alveolar compound A concentrations were quantified. Urine mercapturic acids and 3,3,3-trifluoro-2-fluoromethoxypropanoic acid concentrations were measured by gas chromatography and mass spectrometry. RESULTS: Sevoflurane exposure was 3.7 +/- 2.0 MAC-h. Inspired compound A maximum was 29 +/- 14 ppm; area under the inspired concentration versus time curve (AUCinsp) was 78 +/- 58 ppm x h. Compound A dose, calculated from pulmonary uptake, was 0.39 +/- 0.35 mmol (4.8 +/- 4.0 micromol/kg) and correlated with AUCinsp (r2 = 0.84, P < 0.001). Mercapturic acids excretion was complete after 2 days, whereas 3,3,3-trifluoro-2-fluoromethoxypropanoic acid excretion continued for 3 days in some patients. Total (3-day) mercapturates and fluoromethoxypropanoic acid excretion was 95 +/- 49 and 294 +/- 416 micromol, respectively (1.2 +/- 0.6 and 3.6 +/- 5.0 micromol/kg). CONCLUSION: Compound A doses during 3.7 MAC-h, low-flow sevoflurane administration in humans are substantially less than the threshold for renal toxicity in rats (200 micromol/kg). Compound A metabolites quantification may provide a biomarker for compound A exposure and relative metabolism via toxification and detoxication pathways. Compared with previous investigations, relative metabolic flux (fluoromethoxypropanoic acid/mercapturates) through the toxification pathway was sixfold greater in rats than in humans. Species differences in dose and metabolism may influence compound A renal effects.

Assessment of low-flow sevoflurane and isoflurane effects on renal function using sensitive markers of tubular toxicity.

BACKGROUND: Carbon dioxide absorbents degrade sevoflurane, particularly at low gas flow rates, to fluoromethyl-2,2-difluoro-1-(trifluoromethyl)vinyl ether (compound A). Compound A causes renal proximal tubular injury in rats but has had no effect on blood urea nitrogen (BUN) or creatinine concentrations in patients. This investigation compared the effects of low-flow sevoflurane and isoflurane on renal tubular function in surgical patients using conventional (BUN and creatinine) and finer indices of renal injury, specifically those biomarkers sensitive for compound A toxicity in rats (glucosuria, proteinuria, and enzymuria [N-acetyl-beta-D-glucosaminidase (NAG) and alpha-glutathione-S-transferase (alpha GST)]). METHODS: Consenting patients with normal preoperative renal function at two institutions were randomized to receive sevoflurane (n = 36) or isoflurane (n = 37) in oxygen and air. Total gas flow was 1 l/min, opioid doses were minimized, and barium hydroxide lime was used to maximize anesthetic degradation. Inspiratory and expiratory compound A concentrations were quantified every 30-60 min. Blood and urine were obtained before and 24-72 h after anesthesia for laboratory evaluation. RESULTS: Sevoflurane and isoflurane groups were similar with respect to age, weight, sex, American Society of Anesthesiologists status, anesthetic duration (3.7 or 3.9 h), and anesthetic exposure (3.6 or 3 minimum alveolar concentration [MAC]-hour). Maximum inspired compound A concentration (mean +/- standard deviation) was 27 +/- 13 ppm (range, 10-67 ppm). Areas under the inspired and expired compound A concentration versus time curves (AUC) were 79 +/- 54-ppm-h (range, 10-223 ppm-h) and 53 +/- 40 ppm-h (range, 6-159 ppm-h), respectively. There was no significant difference between anesthetic groups in postoperative serum creatinine or BUN, or urinary excretion of protein, glucose, NAG, proximal tubular alpha GST, or distal tubular pi GST. There was no significant correlation between compound A exposure (AUC) and protein, glucose, NAG, alpha GST, or pi GST excretion. Postoperative alanine and aspartate aminotransferase concentrations were not different between the anesthetic groups, and there were no significant correlations between compound A exposure and alanine or aspartate aminotransferase concentrations. CONCLUSIONS: The renal tubular and hepatic effects of low-flow sevoflurane and isoflurane were similar as assessed using both conventional measures of hepatic and renal function and more sensitive biochemical markers of renal tubular cell necrosis. Moderate duration low-flow sevoflurane anesthesia, during which compound A formation occurs, appears to be as safe as low-flow isoflurane anesthesia.