Chemical analysis of fresh and aged Australian e-cigarette liquids.

OBJECTIVES: To assess the chemical composition of electronic cigarette liquids (e-liquids) sold in Australia, in both their fresh and aged forms. DESIGN, SETTING: Gas chromatography-mass spectrometry analysis of commercial e-liquids sold in Australia (online and physical stores). MAIN OUTCOME MEASURES: Chemical composition of 65 Australian e-liquids - excipients/solvents, flavouring chemicals, other known e-liquid constituents (including nicotine), and polycyclic aromatic hydrocarbons - before and after an accelerated ageing process that simulated the effects of vaping. RESULTS: The measured levels of propylene glycol and glycerol often diverged from those recorded on the e-liquid label. All e-liquids contained one or more potentially harmful chemicals, including benzaldehyde, menthol, trans-cinnamaldehyde, and polycyclic aromatic hydrocarbons. Nicotine or nicotyrine were detected in a small proportion of e-liquids at extremely low concentrations. CONCLUSIONS: Australian e-liquids contain a wide variety of chemicals for which information on inhalation toxicity is not available. Further analyses are required to assess the potential long term effects of e-cigarette use on health.

Plasma acrolein level in rheumatoid arthritis increases independently of the disease characteristics.

OBJECTIVE: This study aimed to clarify whether plasma acrolein level actually increases in rheumatoid arthritis (RA) patients, and to elucidate whether any relationship exists between the levels and the RA background variables. METHODS: Plasma levels of protein-conjugated acrolein (PC-Acro) in 84 patients (RA group) and 298 normal individuals (Control group) were measured by enzyme-linked immunosorbent assay procedures. The data were statistically analyzed with Wilcoxon rank-sum test, multiple logistic regression analyses and Spearman's rank correlation coefficient. RESULTS: The RA group showed significantly higher PC-Acro levels than the Control group (median [interquartile range]: 80.5 [63.2-105.2] and 65.9 [58.9-78.1] nmol/ml, respectively). Of background factors giving influence to PC-Acro level in the combination of the two groups, 'diagnosis of RA positive' indicated strong correlation to high PC-Acro level (odds ratio: 2.96; 95% confidence interval: 1.54-5.71). These increases of PC-Acro in the RA patients did not correlate to their disease duration and/or inflammatory variables: PC-Acro level could elevate even in early RA patients showing negative inflammatory findings. CONCLUSION: Plasma levels of PC-Acro increased with RA, but the levels did not correlate with RA background variables. This report provides the basis for further studies of early diagnosis of RA as well as its pathogenesis.

Real-time process quality control of ramulus cinnamomi by critical quality attribute using microscale thermophoresis and on-line NIR.

Real-time process quality control of ramulus cinnamomi (cassia twig) is still a challenge in pharmaceutical industry. Rapid critical quality attribute (CQA) determination of ramulus cinnamomi is essential for quality control. Microscale thermophoresis (MST) was used to investigate the CQA of ramulus cinnamomi by the interaction with biomacromolecule. There was a good affinity between cinnamaldehyde and human serum albumin (HSA) with Ka as 2.1722×103mol/L. It was an excellent combination of similarity to ibuprofen with same binding force as discovered as hydrogen bond and van der Waals force. Furthermore, regarding cinnamaldehyde as CQA, on-line near-infrared was used to monitor pilot extraction process of ramulus cinnamomi combined with high performance liquid chromatography (HPLC). Quantitative model was established with Rpre2 as 0.9798 and RMSECV as 0.0993, suggesting the NIR model was so robust and accurate for pilot process quality control. This method provided a perfect guideline for rapid CQA determination and real-time process quality control of Chinese materia medica (CMM) based on a vital CQA.

Human exposure to acrolein: Time-dependence and individual variation in eye irritation.

The aim of the study was to examine the time dependence on sensory irritation detection following exposure to threshold levels of acrolein, in humans. The exposures occurred in an exposure chamber and the subjects were breathing fresh air through a mask that covered the nose and mouth. All participants participated in four exposure conditions, of which three consisted of a mixture of acrolein and heptane and one of only heptane. Exposure to acrolein at a concentration half of the TLV-C lead to sensory irritation. The perceived sensory irritation resulted in both increased detectability and sensory irritation after about 6.8min of exposure in 58% of the participants. The study confirm the previously suggested LOAEL of about 0.34mg/m(3) for eye irritation due to acrolein exposure. The sensory irritation was still significant 10min after exposure. These results have implications for risk assessment and limit setting in occupational hygiene.

Occupational exposures among personnel working near combined burn pit and incinerator operations at Bagram Airfield, Afghanistan.

Occupational air samples were collected at Bagram Airfield Afghanistan for security forces (SF) stationed at the perimeter of the solid waste disposal facility that included a burn pit, air curtain destructors, and solid waste and medical waste incinerators. The objective of the investigation was to quantify inhalation exposures of workers near the disposal facility. Occupational air sample analytes included total particulates not otherwise specified (PNOS), respirable PNOS, acrolein and polyaromatic hydrocarbons (PAH). Exposures were measured for four SF job specialties. Thirty 12-hour shifts were monitored from November 2011 to March 2012. The geometric means for respirable particulate matter and PAH for all job specialties were below the 12-hour adjusted American Conference of Governmental Industrial Hygienists threshold limit value time weighted averages (TLV-TWA). The geometric mean of the respirable particulate matter 12-hour TWAs for the four job specialties ranged from 0.116 to 0.134 mg/m(3). One measurement collected at the tower (3.1 mg/m(3)) position exceeded the TLV-TWA. Naphthalene and pyrene were the only PAHs detected in multiple samples of the 18 PAHs analyzed. The geometric mean concentration for naphthalene was 9.39E-4 mg/m(3) and the maximum concentration was 0.0051 mg/m(3). The geometric mean of acrolein for the four job specialties ranged from 0.021 to 0.047 mg/m(3). There were four exceedances of the Occupational Safety and Health Administration 8-hour permissible exposure limit- time weighted average (PEL-TWA), respectively, ranging from 0.13 to 0.32 mg/m(3).

Effect of variable power levels on the yield of total aerosol mass and formation of aldehydes in e-cigarette aerosols.

The study objective was to determine the effect of variable power applied to the atomizer of refillable tank based e-cigarette (EC) devices. Five different devices were evaluated, each at four power levels. Aerosol yield results are reported for each set of 25 EC puffs, as mass/puff, and normalized for the power applied to the coil, in mass/watt. The range of aerosol produced on a per puff basis ranged from 1.5 to 28 mg, and, normalized for power applied to the coil, ranged from 0.27 to 1.1 mg/watt. Aerosol samples were also analyzed for the production of formaldehyde, acetaldehyde, and acrolein, as DNPH derivatives, at each power level. When reported on mass basis, three of the devices showed an increase in total aldehyde yield with increasing power applied to the coil, while two of the devices showed the opposite trend. The mass of formaldehyde, acetaldehyde, and acrolein produced per gram of total aerosol produced ranged from 0.01 to 7.3 mg/g, 0.006 to 5.8 mg/g, and <0.003 to 0.78 mg/g, respectively. These results were used to estimate daily exposure to formaldehyde, acetaldehyde, and acrolein from EC aerosols from specific devices, and were compared to estimated exposure from consumption of cigarettes, to occupational and workplace limits, and to previously reported results from other researchers.