- The main biosafety risk associated with handling primary cell cultures derived from non-human primates is the exposure to latent viruses such as Herpesvirus simiae.
- Non-human primates are known to harbor several latent viruses that can be reactivated during cell culture.
- Among these, Herpesvirus simiae (also known as B virus) is of particular concern because it can cause severe and potentially fatal infections in humans.

- It is important to recognize that while endotoxin contamination (Option 1) and antibiotic resistance (Option 3) are general laboratory concerns, they do not specifically represent the primary biosafety hazard unique to non-human primate-derived cells.
- Similarly, the formation of tumorigenic cell lines (Option 4) relates more to cell transformation studies and is not the main biosafety concern in this context.

- Proper biosafety level protocols, including the use of personal protective equipment (PPE) and working within biosafety cabinets, are essential to minimize the risk of viral exposure from these primary cultures.

Key points:
- Non-human primate cells may harbor latent viruses, notably Herpesvirus simiae.
- Herpesvirus simiae can cause serious infection in humans if accidentally transmitted.
- Adherence to strict biosafety measures is crucial when handling these cultures.

Reference: Biological Safety: Principles and Practices, 5th Edition, Chapter 8, Pages 225-230