Theyâ€™ll cause a lot of health problems if they aren't.
CFL lamps, HID lamps and old-type ballasts contain certain chemicals that are important for their function. Unfortunately, these chemicals are very harmful to health.
In order for them to light up, Fluorescent (and CFL) lamps and High Intensity Discharge lamps contain harmful mercury vapor. Although the average amount of mercury in fluorescent lamps went down from 50 mg in the 1970s to around 7.5 mg in 2007 (around 4.0 mg now; HID lamps have higher mercury contentâ€”from 50 mg up to 1000 mg), this amount can be accidentally inhaled if the lamps are broken indoors. Thatâ€™s why the U.S. Environmental Protection Agency (EPA) advises people to leave the room and keep it well ventilated for at least 15 minutes if a fluorescent light bulb is broken indoors.
EPA also recommendeds a special cleanup procedure for broken fluorescent lamps.
old 'wet-type' ballasts, on the other hand, contain polychlorinated biphenols (PCBs) before 1979, or di (2-ethylhexyl) phthalate (DEHP) from 1979 to 1991.
This type of ballast used PCBs/DEHPs as packing material in their transformers and capacitors. When these chemicals leak out into the environment, they accumulate (biomagnify) up the food chain, threatening animal and plant reproduction and cause certain cancers.
Accordingly, EPA says you must treat a leaking wet ballast (made before 1991) as hazardous waste.
The best way to dispose of unused lamps and ballasts is to send the unusable lamps to designated recycling centers, where they have special equipment to recycle the mercury and glass from the lamps and to incinerate old ballasts.