A new risk for the recovered Tibetan antelope (Pantholops hodgsonii): Co-exposure of microplastics with organophosphates in their habitats

Emerging contaminants (ECs), particularly microplastics (MPs) and organophosphate esters (OPEs), poses a new potential threat to the recovered Tibetan antelope on the Qinghai-Tibet Plateau (QTP). However, very little is known about the environmental exposure of ECs and their impacts on wildlife on the QTP. Accordingly, we first conducted investigations of six major Tibetan antelope habitats on the QTP, and found widespread presence of MPs and OPEs in topsoil, surface water, sediments, air and Tibetan antelope feces there. A total of 11 OPEs were detected, with chlorinated OPEs (like TCPP: 2.8 ng/g soil, 9.0 ng/g feces) being most prevalent. MPs (35 polymer types) were identified in all topsoil, air suspended particle and feces samples, with antelope exposure estimated at 2.9 × 10-13.8 × 10 particles/year. Noteworthy, MPs carried adsorbed OPEs, providing direct evidence of co-exposure, and in vivo evaluations demonstrated that co-exposure (polystyrene-MPs loaded with TCPP) caused significant anxiety-like behaviors and cognitive deficits in mice, effects far worse than exposure to either EC alone. This highlights the synergistic neurotoxic potential of combined ECs. This study underscores the urgent need to further research the ecological risks of ECs co-exposure to endangered species like the Tibetan antelope to strengthen conservation efforts.