http://news.independent.co.uk/sci_tech/article3081833.ece
...tested for toxic substances.
Half of them tested positive for bromine, ...
Four items also tested positive for antimony, a toxic mineral often used with flame retardants, and others contained very small amounts of chromium and lead. Chlorine was found in the plastic coating of the headphone cables, indicating the presence of PVC.
...
the discovery of phthalates, used to make plastic more flexible, in the cable coating. The chemicals are suspected of causing birth defects and gender-bending effects. ...
It believes the company may prefer to eliminate the materials rather than face the stigma of carrying a warning label.
...
Greenpeace says that all the chemicals found would be allowed under European law