Only 3.2 million of the estimated 10 million lightbulbs sold in 2019 were recycled, according to Waste, Electrical and Electronic Equipment Ireland. That leaves up to 6.8 million bulbs which could have been sent to landfill via household rubbish bins. This creates a severe health and environmental hazard as many bulbs are fluorescent and compact fluorescent lamps, which can contain traces of mercury and other very harmful chemicals.