Analysis of Drifting Polystyrene Degradation Surround Japan

Research Article

Austin J Environ Toxicol. 2020; 6(1): 1030.

Analysis of Drifting Polystyrene Degradation Surround Japan

Amamiya K1, Koizumi K2, Yamada K1, Hiaki T1, Kusui T4 and Saido K1,3*

¹College of Industrial Technology, Nihon University, Japan

²College of Science & Technology, Nihon University, Japan

³Albatross Alliance, Japan

4Toyama Prefecture University, Japan

*Corresponding author: Katsuhiko Saido, College of Industrial Technology, Nihon University, Chiba, Japan

Received: January 09, 2020; Accepted: February 06, 2020; Published: February 13, 2020


Due to accidental or intentional littering, plastics make their way into rivers and ultimately into oceans. No studies have been conducted on plastic decomposition at low temperatures in the ocean owing to the misconception that plastic hardly decomposes, if at all. To clarify if drifting plastics do indeed break down or not. Not only does this happen through micro/nano-scale fragmentation, but also potentially noxious chemicals are generated. To examine the level of chemical contamination of ocean bodies due to debris/waste Polystyrene (PS), 2,000 sand and water samples surrounding Japan were analyzed by GC/MS since 2,000 to 2015. All samples containing styrene oligomer (SOs) which consist of ethynylbenzene (Styrene Monomer, SM), 2,4-diphenyl-1-butene (Styrene Dimer, SD) and 2,4-6-triphenyl-1-hexene (Styrene Trimer, ST). The composition ratios were SM1: SD1: ST 7 to10. Mega/Macro debris PS not only fragmented to generate micro/nano PS-particles (micro/nano plastic) but also chemically degraded to basic structure unite chemicals SOs.

One Sentence Summary: PS in the ocean breaks into its oligomer at ambient temperatures throughout the year, posing a serious threat to marine ecosystems.

Keywords: Marine debris plastic; Polystyrene; Degradation; Styrene ligomer; Contamination


World plastic production had reached 1.5×106 metric tons (1,500 million kilograms) in 1950 and increased to 322×106 metric tons (322 billion kilograms) in 2015 [1,2]. Accidentally or intentionally, the release of this plastic waste from land sources will ultimately make its way to oceans all over the world [3-5]. Two types of plastic have been shown to have adverse effect on oceans—drifting plastic, which traps marine animals and causes digestive disorders [6,7] and acuminate persistent organic pollutants (POPs) in the plastic. Lebereton et al. confirmed that these plastics have been on the rise in ocean “garbage patches” [8] around the world. The POPs on the other hand are organic wastes that persist for long periods of time on the ocean surface [9,10]. Although plastics are durable, in oceans, they eventually undergo extensive chemical fragmentation into pieces less than 5 mm in diameter, which are called micro/nano-plastics [11,12]. These pieces are digested by the planktons [13,14]. Plastic fragments ingested by larger marine species and smaller plankton or accumulating elsewhere are still suspected of damaging the marine biota [15,16].

This research article presents a first-of-its-kind extensive study on the degradation of PS at sea surface temperatures. Over 2,000 sand and water samples taken from surrounding Japan at different time periods were analyzed for SOs which generated chemical degradation products of PS at ambient temperature. All the samples with PS were shown to contain SOs surround Japan coast lines.


Reagents/samples and analyzers

The extractant Di Chloro Methane (DCM) to SOs from sand and seawater, a pesticide analysis reagent manufactured by Kanto Chemical Co, Ltd. was used. For SM, a special grade reagent manufactured by Wako Pure Chemical Industries, Ltd. was used after purification by distillation. 2,4-diphenyl-1-butene (Styrene Dimer: SD2) and 2,4,6-triphenyl-1-hexene (ST) decompose PS and purify by boiling fractionation under reduced pressure [5]. The purity of each reagent was analyzed by Gas Chromatography (GC) equipped with H-FID detector, and confirmed to be 99.8% or more were used. For 1, 3-diphenylpropane (styrene dimer: SD1), a special grade reagent manufactured by Wako Pure Chemical Industries, Ltd. was used. The Phenan Threne (PT), internal standard and surrogate Substance Biphenyl (BP) were used after purifying a special grade reagent manufactured by Wako Pure Chemical Industries, Ltd. by a sublimation method. GC used in the analysis was HP6890 manufactured by Agilent, the Mass Spectrometer (MS) was JMS-AMII manufactured by JEOL Ltd., and the column was DB-1 manufactured by Agilent @ J & W. The analytical operating conditions were shown in Table 1.