 There is a near universal system for assessing the relative risks associated with GMOs and other agents to laboratory staff and the community.They are assigned to one of four risk categories based on their virulence, the severity of disease, the mode of transmission, and the availability of preventive measures or treatments.There are four biosafety levels that a laboratory can fall into, ranging from level 1 (which is suitable for working with agents not associated with disease) to level 4 (working with life-threatening agents).