Determination of chemicals released from single use low density polyethylene plastic bags

Abstract

The use of plastics has increased manifold, owing to their inexpensive, multipurpose, durable and lightweight nature. Plastics are made with various types of polymer, including Low Density Polyethylene (LDPE). In Myanmar, many foods are packaged in single use LDPE plastics including fresh meat, vegetables, fast foods, and even some hot foods in daily life. Therefore the present study was aimed to determine the chemicals released from single use LDPE plastic bags that were used in direct contact with hot foods. Fourier Transform Infra-Red (FTIR) spectroscopy analysis was done for confirmation of LDPE. Extraction of chemicals from single use plastic bags was carried out by reflux extraction method by using four types of solvents (chloroform, ethanol, distilled water and olive oil). The individual chemicals released from the sample were determined by Gas Chromatography-Mass Spectrometry (GC-MS) with National Institute of Standard and Technology (NIST) library. GC-MS results of different extracts were hexadecanoic acid octyl ester (26.09%), octadecanoic acid octyl ester (19.96%), tetracosane (13.36%) and 9-octadecanoic acid methyl ester (9.28%) from distilled water extract;3-methoxy 2,2-dimethyloxirane (84.26%), 2,3-dihydro-1,4-dioxin (3.77%), 1-ethoxy pantane (2.85%) and tetracosane (2.65%) from ethanolic extract; toluene (69.30%), ethyl benzene (18.11%), 1,1-dipropoxypropane (4.02%) and dipropoxy methane (1.56%) from chloroform extract; and supraene (76.81%), nonanal (3.09%), 2-decenal (2.97%), 2-undecenal (3.05%) and toluene (1.35%) from olive oil extract respectively. According to the Wavelength Dispersive X-ray Fluorescence (WDXRF) analysis of single use plastic bag, the different concentrations of elements were found to be titanium (0.0587 %), chlorine (0.0093 %) and strontium (0.0026 %) and so on. The present study revealed that single use LDPE plastic bags contained some chemicals that are toxic to human beings such as toluene, ethyl benzene, methyl oxirane, supraene and some type of aldehyde, and even carcinogenic substance like dioxin. Therefore it is necessary to limit the use of harmful additives and packaging of hot foods in single use LDPE plastic bags.