Participation in an international occupational semen study
| Site | Workplaces | Source populations*† (n) | Semen providers (n) | Participation rate (%) |
|---|---|---|---|---|
| *Eligibility criteria: current employment at the selected workplace and age between 18 and 55 years; †the source population is the group of eligible men who were invited to participate in the study. In Italy, men were selected for the study by their blood lead concentration to obtain a balanced contribution of men with different levels of exposure. This group comprised 10%–15% of the total number of workers in the referent companies and 20%–25% of the total number in the companies with exposure to lead. | ||||
| England: | 884 | 199 | 23 | |
| Exposed | Smelter, batteries | 652 | 143 | 22 |
| Referents | Internal | 232 | 56 | 24 |
| Italy: | 146 | 140 | 96 | |
| Exposed | Foundries, batteries | 101 | 95 | 94 |
| Referents | Security service | 45 | 45 | 100 |
| Belgium: | 1816 | 164 | 9 | |
| Exposed | Smelter | 903 | 68 | 8 |
| Referents | University hospital | 913 | 96 | 11 |
| All: | 2846 | 503 | 18 | |
| Exposed | 1656 | 306 | 18 | |
| Referents | 1190 | 197 | 17 | |