It is an indicator of how a chemical will behave in the workplace. The higher the number the more the chemical will evaporate into the air. VOC Volatile organic compound. The units are kilo Pascals. Hydroquinone is considered to be a sensitiser, although this effect is seen in very few cases.
Many chemicals can produce some evidence of cancer in animals.
Where this is the case details can be found on the relevant safety data sheets. A highly respected USA organisation which produces workplace health and safety information. This section gives information about the hazards during transport associated with any given product. In addition to some similarities with the workplace health and safety bottle label information, corrosion to the metals steel and aluminium are also included here. The chemical in the product giving rise to the transport classification is always stated on the outer transport packaging.