I remember there was a lot of noise made about the Hg content in the power saving lights when the adds first appeared to promote them as a good alternative. Somehow it got swept under the carpet and people have bought them in droves (none in my house I will keep feeding the plants instead). The Hg combines with other elements to make salts that play merry hell on the nervous system if they build up in high enough concentrations. Anybody for "mad hatters disease"
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Mark