First Evidence of Contamination in Aquatic Organisms with Organic Light-Emitting Materials

Organic light-emitting materials (OLEMs) play an irreplaceable role in electronic display screens, and some of them have been proposed to be persistent, bioaccumulative, and toxic. They were detected in indoor dust, sediment, and landfill leachates. However, until now, no information has been available about their contamination in biota samples. Here, we developed a novel atmospheric pressure gas chromatography-tandem mass spectrometry-based analytical method to quantitatively determine OLEMs in biota samples and reveal the contamination of OLEMs in 32 species of wild aquatic invertebrates and fishes. Twenty-nine of the 30 target OLEMs analyzed were detected in aquatic organisms, including 16 liquid crystal monomers (LCMs) and 13 OLEMs employed in organic light-emitting diode (OLED) displays. The total concentrations of OLEMs in invertebrates ranged from not detected (N.D.) to 7.36 ng/g wet weight (ww) with a median of 0.13 ng/g ww, and in fish, they ranged from N.D. to 29.7 ng/g ww with a median of 9.5 ng/g ww. Thus, the present study established a sensitive analytical method for OLEM quantification in tissue samples and provided the first evidence for contamination of OLEMs in wildlife.