Emission fluxes of styrene monomers and other chemicals for products containing expanded polystyrene beads.

Atsushi Iizuka,Atsushi Mizukoshi,Miyuki Noguchi,Akihiro Yamasaki,Julian Aherne

doi:10.1371/journal.pone.0239458

Atsushi Iizuka, Atsushi Mizukoshi + Show 3 more

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https://doi.org/10.1371/journal.pone.0239458

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Journal: PloS one	Publication Date: Oct 1, 2020
Citations: 7	License type: CC BY 4.0

Affiliation: Tohoku University, Kindai University

Abstract

Styrene in indoor air can adversely affect human health. In this study, styrene monomer and other chemical emission fluxes for products containing expanded polystyrene beads (pillows, cushions, and soft toys) were measured at various temperatures to simulate typical product use. The contributions of the products to styrene and other chemical concentrations in indoor air and human exposure to these chemicals were estimated, and health risk assessments were performed. The styrene monomer emission fluxes for the samples at 25°C were between 25.3 and 8.73×103 μg/(m2 h). The styrene emission fluxes for the product surfaces increased strongly as the temperature increased, from between 124 and 2.44×104 μg/(m2 h) at 36°C (simulating human body temperature) to between 474 and 4.59×104 μg/(m2 h) at 50°C (simulating inside an automobile in summer). The hexane, heptane, toluene, octane, ethylbenzene, m- and p-xylene, o-xylene, and dodecane emission fluxes at 25°C for the sample that emitted the analytes most readily were high. The maximum estimated styrene and xylene concentrations in indoor air caused by emissions from expanded polystyrene beads at 36°C in a bedroom and automobile were higher than the relevant guidelines. The maximum contribution of a product containing expanded polystyrene beads in a living room, bedroom, or automobile could cause the total volatile organic compound concentration in air to exceed the advisable value (400 μg/m3). The estimated maximum hazard quotients for styrene, toluene, and xylene emitted by a product containing expanded polystyrene beads at 36°C in a bedroom were 0.59, 0.30, and 0.37, respectively. These non-carcinogenic risk values for single products could contribute to the non-carcinogenic risk thresholds being exceeded when multiple products and other sources of chemicals are taken into consideration. The estimated styrene concentrations suggest that products containing expanded polystyrene beads are important sources of styrene to indoor air.

Highlights

The styrene emission fluxes were much higher than the styrene emission flux of 3.4 μg/(m2 h) for high-impact polystyrene found by the Japan Styrene Industry Association (JSIA) [12]
It should be noted that the total amounts of styrene monomers in the products were not very large, so the styrene emission flux would have decreased over time
It is important for temporal variations in the chemical fluxes for products containing Expanded polystyrene beads (EPSBs) over long periods to be determined in a future study

Summary

Introduction

We published a study in 2010 [13] in which we measured styrene and other chemical emission fluxes for the surfaces of three pillows, three cushions, and two soft toys containing EPSBs. The emission fluxes increased markedly with increasing temperature (tests were performed at 25, 36, and 50 ̊C). The aim of the study presented here was to measure styrene monomer and other chemical emission fluxes for various products (pillows, cushions, and soft toys) that contain EPSBs at different temperatures to simulate typical daily activities and locations.

Results

Conclusion