One of the common reasons for halogen elimination in electronics is based around the possibility that halogens can form dioxins when that halogenated product is burned. Dioxins are considered to be likely carcinogens. During uncontrolled incineration, the dioxins can be breathed in by any person or animal in close proximity to the fire. In a photograph published last year by National Geographic (shown here), you can see an indivdual in India buring the insulation off of copper wires in an open pit. Copper has value, but most companies won't buy back copper with the insulation on them. Therefore, this individual has decided the easiest way is to just burn it off. The wires most likely have PVC coatings on the outside which does contain the halogen chlorine. By buring the halogenated wires, this person is putting his own life and others nearby at risk. I can't find the source right now, but it was documented that about 40% of dioxins in the air are a result of "backyard" or open pit burning of materials. My personal opinion is that we can eliminate the halogens to reduce dioxin formation, but does that really make these types of burning practices "safe?" I don't think so...