What symbol indicates a toxic substance according to the Globally Harmonized System (GHS)?

The symbol that indicates a toxic substance according to the Globally Harmonized System (GHS) is the skull and crossbones. This symbol is universally recognized as a graphic representation of hazards related to toxic materials. When this symbol appears on a label, it signifies that the substance presents a serious risk of acute toxicity, meaning it can cause severe harm or death following exposure, ingestion, or inhalation.

The prominence of this symbol in the context of safety communication is crucial because it alerts individuals to the dangers associated with handling such materials. The skull and crossbones serves as an immediate visual cue, making it easier for workers and the public to recognize potential hazards quickly.

In contrast, while the flame symbol indicates flammable materials, the exclamation mark signifies general hazards such as skin irritation or respiratory issues, and the health hazard symbol is used for substances that may cause serious health effects such as carcinogenicity or respiratory sensitization. Each of these symbols serves a distinct purpose within the GHS framework, but the skull and crossbones specifically denotes toxicity, marking its significance in identifying potentially lethal substances.