| Contamination factors | Number (n = 300) | Frequency (%) |
| Type of utensil and packaging used | ||
| Plastic plate | 64 | 21.3 |
| Aluminum plate | 33 | 11.1 |
| Cement packaging | 148 | 49.3 |
| Aluminum foil | 55 | 18.3 |
| Point-of-sale devices | ||
| Exposure to the open air | 248 | 82.5 |
| Protection in show case | 52 | 17.4 |
| Wearing the blouse (Body hygiene) | ||
| Yes | No | |
| 70 (23.3%) | 230 (76.6) | |