ABSTRACT
Abstract@#Introduction: The electronic cigarette (EC) usage has raised public health concerns; whether its advantages to smokers as a potential smoking cessation aid have outweighed its negative health impacts among EC users. This study aims to estimate health risks associated with chemical exposures to nicotine, propylene glycol (PG) and selected Tobacco-Specific Nitrosamines (TSNAs) namely 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N’-nitrosonornicotine (NNN) in e-liquids locally-manufactured in Malaysia. Methods: The health risk assessment (HRA) was performed using established guideline by the Environmental Protection Agency (EPA). The average daily dose (ADD) and lifetime average daily dose (LADD) were calculated using previously published data on chemical concentration of selected compounds and local EC usage topography data. Next, the non-carcinogenic risk (nicotine and PG) and carcinogenic risk (NNK and NNN) were calculated and denoted as total hazard quotient (HQT) and total lifetime cancer risk (LCRT) value, respectively. Results: For non-carcinogenic risk, the mean of HQT was 78.9 which falls under “unacceptable” risk as demonstrated by HQT value of more than 1. While for carcinogenic risk, the mean of total LCRT value was 1.54E-04 which may place EC users at risk of developing cancer resulted from exposure to selected TSNAs. Conclusion: Comprehensive HRA using currently available data of local EC usage topography and chemical evaluation of Malaysian-made e-liquids have revealed that the exposure to nicotine, PG and selected TSNAs are expected to be a significant health concern for local EC users. This finding supports the local health authority to issue a stringent health policy in considering EC as a tool for smoking cessation among heavy smokers.
ABSTRACT
@#Introduction: Electronic Cigarette (EC) usage has been gaining acceptance in Malaysia despite its lack of analytical evidence on the chemical constituents of its liquid formulations. This study aims to evaluate the chemical concentrations of nicotine, propylene glycol (PG) and selected Tobacco-Specific Nitrosamines (TSNAs); 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) and N’-nitrosonornicotine (NNN) in e-liquids locally sourced from the Malaysian market. Methods: A total of 17 e-liquids from a variety of flavours and brands were purchased from local EC retailers in Klang Valley, Malaysia. Nicotine and PG concentrations were assessed using Gas Chromatography-Flame Ionization Detector (GC-FID) while NNK and NNN were quantified using Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS). The concentrations of nicotine and PG (mg/mL) were described in comparison with the levels indicated on the labels when present while levels of TSNAs were descriptively explained. Results: Nicotine was detected in all e-liquid samples, despite several samples being declared as nicotine-free. The average (standard deviation) level of nicotine, PG, NNN and NNK were 3.26 (1.04) mg/mL, 484.10 (98.24) mg/mL, 0.383(0.288) µg/L and 0.086 (0.057) µg/L, respectively. Labelling discrepancies (when indicated on the label) of nicotine and PG were between the range of 27%-73% and 3%-63%, respectively. Conclusion: The concentrations of nicotine and PG in local e-liquids were varied. There were evidences of labelling discrepancy in that local e-liquids. TSNAs were detected in all samples of e-liquids. This study brought forth strong evidence on the need for the implementation of regulation on e-liquid manufacturing and sales, particularly on the accuracy of labelling and licensing to protect the public health.