No, in contrast to energy-saving lamps, LED luminaires contain no toxic substances such as mercury.
When improperly used, light from blue LEDs can damage the eyes. However, luminaires usually contain colour-converted LEDs that have a smaller blue component and specific optics. The possibility of eye damage can be excluded if LED luminaires and LED lamps are used correctly.
The energy balance of a retrofit LED lamp is comparable to that of an energy-saving lamp but the lighting quality of the LED version is significantly better. What is more, the LED lamp does not contain toxic mercury.
LEDs are disposed of in accordance with the applicable directives (WEEE), together with the electronics of the luminaire. The industry has set up special collection schemes for this purpose. Retrofit LED lamps from private households are disposed of as electronic scrap at appropriate collection points.
Examples of new applications include hybrid luminaires which combine LEDs and conventional light sources, energy-efficient LED downlights and spotlights, and innovative LED façade solutions and streetlights.
Yes, LEDs are now suitable for many professional applications.
References: Sustainability Report 2010/11