A parliamentary commission in Belgium has begun hearings to investigate the political responsibilities behind the recent dioxin crisis.

The scandal broke in May when all Belgian poultry and eggs had to be withdrawn from sale because it was found farmers had used poultry food contaminated with dioxin -- an extremely dangerous cancer-inducing chemical.

Among other issues, the parliamentary inquiry will question the former Belgian health and agriculture ministers, who resigned following the scandal, about why the presence of dioxin in Begian poultry was kept a secret for a month before an alert was issued.