In this perspective paper, we discuss the negative impacts of plastics and associated chemicals on the triple planetary crisis of environmental pollution, climate change and biodiversity loss from a multidisciplinary perspective. Plastics are part of the pollution crisis, threatening ecosystems and human health. They also impact climate change and accelerate biodiversity loss; in this, they aggravate the triple planetary crisis. We analyze the scientific state-of-the-art to identify critical knowledge gaps regarding the life cycle, release, fate, exposure, hazard and governance of plastics and associated chemicals, as well as links to climate change and biodiversity loss. Based on the outcome, we derive key research needs for a comprehensive hazard assessment of plastics and associated chemicals, amongst others, to address the largely missing regulation of plastic additives and in-use plastics. We offer a holistic perspective bridging disciplinary expertise from natural and social sciences to achieve effective plastic governance and risk management of plastics and associated chemicals that protect the Earth, its ecosystems and human health from the plastics crisis.