El mercurio en las bombillas de bajo consumo

1. Why is mercury tolerated in compact fluorescent light bulbs?

The SCHER opinion states:

1. Background
Certain energy-saving light bulbs, namely compact fluorescent lamps (CFLs), are widely available on the market and are offered for saving electricity. They also eventually reduce carbon dioxide emissions particularly from coal-fired power plants. They fulfil the requirements of Commission Regulation (EC) No 244/2009 on ecodesign requirements for non-directional household lamps1 (Ecodesign Regulation), in contrast to traditional incandescent light bulbs which will be phased out progressively in accordance with the Regulation.

According to Directive 2002/95/EC on the restriction of hazardous substances in electrical and electronic equipment (RoHS Directive), a mercury content in CFLs not exceeding 5 mg per lamp is allowed (the mercury exemption for CFLs is listed as n°1 in the Annex to the RoHS Directive). An indicative benchmark (best available technology) of 1.23 mg of mercury in energy efficient CFLs is provided in the above-mentioned Ecodesign Regulation (Annex IV, n° 3 of the Ecodesign Regulation).

The above-mentioned 5 mg mercury tolerance for CFLs is being reviewed on a regular basis, in line with the four-year-review period prescribed by the RoHS Directive. Such reviews aim at assessing whether the elimination or substitution of mercury is technically possible through specific design changes or through the use of other materials, provided that the negative impacts for the environment, health and/or consumer safety generated by the substitution do not outweigh the possible benefits thereof. This is indicated in Article 5 (1.c) of the RoHS Directive.

At the end of 2007, DG Environment commissioned a technical and scientific assessment of this exemption including, among others, consultation of interested stakeholders (e.g. producers of electrical and electronic equipment, environmental organisations and consumer associations). According to this assessment (Öko-Institut and Fraunhofer IZM 2009), finalised in March 2009, the elimination of mercury in CFLs is still technically and scientifically impracticable.

On the basis of this assessment, the Commission will take a decision for the review of this mercury exemption before July 2010, after consultation with the RoHS Technical Adaptation Committee (RoHS Directive, Article 7). In support of any future review, it may further be appropriate to consider the potential risks associated with the release of mercury from a CFL when it accidentally breaks in the hands of a consumer, for example while replacing a CFL. In such a case, long-term toxicological limit values may be exceeded up to 6,000 times, and the consumer's exposure to mercury may only be 10-fold below acute intoxication. Further information can be found in annex 2. Further considerations on the risk from mercury have been published elsewhere (Groth 2008), including in the event of a CFL breakage in a consumer home.

Clean-up of the debris of a broken CFL has been described as complicated, requiring, for example, the removal of the mercury droplets with adhesive tape and their disposal as special waste. This again points to the relevance of the risk caused by the breakage of a CFL in a consumer's home.

As regards the impacts of mercury emissions related to CFLs, the life-cycle of CFLs should be considered so as to weigh the risks of a mercury escape from CFLs, be it by accidental breakage or disposal as waste (instead of an appropriate recycling) against the reduction of mercury emissions from coal-based power plants due to the lower electricity consumption of CFLs (Aucott et al. 2004). Available information indicates that the reduced electricity consumption of CFLs reduces the need for Hg in Energy saving light bulbs electricity, thus the electricity production would release less mercury, and such a decrease could, on balance, save about 10% of the mercury emissions into the environment.

Concerning disposal, Directive 2002/96/EC on waste from electrical and electronic equipment3 (WEEE Directive) requires Member States to adopt appropriate measures in order to minimise the disposal of WEEE, including CFLs, as unsorted municipal waste and to remove mercury from the collected CFLs [see article 5 and Annex II (2) of the WEEE Directive]. A proposal to recast the Directive, made by the Commission in December 2008, strengthens the requirements for separate collection, and specifies that transport of WEEE is to be carried out in a way which optimises the confinement of hazardous substances.

Source & ©: SCHER,  Opinion on Mercury in Certain Energy-saving Light Bulbs (2010), p.5-6.