By Stephen Adams
Abraham Haim, a professor of biology at Haifa University in Israel, said that the bluer light that compact fluorescent lamps (CFLs) emitted closely mimicked daylight, disrupting the body's production of the hormone melatonin more than older-style filament bulbs, which cast a yellower light.
Melatonin, thought to protect against some breast and prostate cancers, is produced and secreted by the brain's pineal gland around the clock.
Highest secretion levels are at night but light depresses production, even if one's eyes are shut.
A possible link between night time light exposure and breast cancer risk has been known for over a decade, since a study was published showing female shift workers were more likely to develop the disease.
Prof Haim explained that a recent study by himself and fellow colleagues had found a much stronger association than previous research between night-time bedroom light levels and breast cancer rates.
Their study, published in the journal Chronobiology International, found breast cancer rates were up to 22 per cent higher in women who slept with a light on, compared to those who slept in total darkness.
They thought one of the reasons for this stronger link could be that people had switched to using energy saving lightbulbs.
They wrote: "In the past decade, light bulbs emitting bluer light waves (~460 nm) have been widely introduced to save energy consumption and reduce CO2 emission."
They quoted another study which showed that exposure to bluer, shorter wavelength light for two hours in the late evening suppressed melatonin production more than the same exposure to yellower light (~550nm), which is more typical of filament bulbs.
The bluer light also made people more alert and increased their body temperature and heart rate.
Prof Haim thought this was because the bluer light from eco-light-bulbs mimicked the stronger light of midday closer than filament bulbs did.
Speaking to The Daily Telegraph, he said he had subsequently removed eco-friendly light-bulbs from his house, as he thought they caused "light pollution".
He said: "Around the world the advice is to change the lights to 'green' bulbs - but they are not really green. They pollute much more light."
Because people thought they were so cheap to run, they were turning on more lights at home, he explained.
He emphasized that the study did not prove that using eco-friendly light bulbs late at night or overnight resulted in higher breast cancer rates than using filament bulbs, and that it remained an unproven theory.
British cancer charities echoed that point.
Jessica Harris, senior health information officer at Cancer Research UK, said: "As this study didn’t investigate low energy ‘eco’ light bulbs and there isn’t any other evidence that they have an effect on breast cancer risk we can’t draw any conclusions about the risk of breast cancer from low energy light bulbs.
"Although it’s far from settled, the evidence that light at night – from any source - could affect breast cancer risk is strengthening and the World Health Organization classify shift working as a 'probable' cause of cancer."
Dr Sarah Rawlings, head of policy at Breakthrough Breast Cancer, said the link was "purely speculative".
"We know there are a number of lifestyle, genetic and environmental risk factors associated with breast cancer, which require more research," she said.
Energy saving light bulbs are not as bright as their traditional counterparts and claims about the amount of light they produce are "exaggerated", the European Union has admitted.
Soon they will be the only kind of light bulb allowed, but now officials in Brussels have admitted that energy-saving bulbs are not as bright as the old-fashioned kind they are replacing.
From tomorrow a Europe-wide ban on traditional incandescent bulbs will begin to be rolled out, with a ban on 100W bulbs and old-style frosted or pearled bulbs.
Buyers of the main type of energy-saving bulb, compact fluorescent lamps (CFLs), are told on the packaging that they shine as brightly as an old-fashioned bulb. For example, an 11W CFL is labelled as being the equivalent of a 60W incandescent bulb.
However, the European Commission, which was responsible for the ban, has now conceded that this is "not true" and that such claims by manufacturers are "exaggerated".
The Sunday Telegraph has conducted its own tests on level of illuminance provided by light bulbs from different manufacturers to see whether their claims stand up to scrutiny.
We found that under normal household conditions, using a single lamp to light a room, an 11W low-energy CFL produced only 58 per cent of the illumination of an "equivalent" 60W bulb – even after a 10-minute "warm-up".
On a website intended to answer consumers' questions about the switch to energy saving bulbs, the European Commission states: "Currently, exaggerated claims are often made on the packaging about the light output of compact fluorescent lamps.
"For example, a 11-12 Watt compact fluorescent lamp would be the equivalent of a 60 Watt incandescent, which is not true. The light output of 15W compact fluorescent lamp is slightly more than the light output from a 60W incandescent."
Under the regulations which are being implemented in the UK from tomorrow, it will be illegal for retailers to import 100W, frosted or pearled incandescent light bulbs, or to sell them once their current stocks have run out. Instead consumers will have to rely upon CFLs or low-energy halogen bulbs.
From September 2011, 60W clear incandescent bulbs will be banned, followed by a ban on all remaining incandescent bulbs in September 2012.
The Department for Food, Environment and Rural Affairs has said it intends to work with retailers to begin phasing out the traditional bulbs sooner.
Many consumers complain that CFLs take time to "warm up", are too big for some lampshade fittings and are more expensive than the traditional bulbs. Special CFLs costing up to £15 each are required to work with dimmer switches.
However, the new-style bulbs use up to 80 per cent less energy than traditional bulbs and can last far longer – up to eight years.
In our test, we used a simple lamp with a light metre placed half a metre away, in an otherwise-darkened room, to measure the illumination provided by a range of clear and frosted 60W incandescent bulbs, as well as 11W CFLs said on their labels to be equivalent.
After giving each bulb 10 minutes to warm up, a reading was taken in lux, a measure of illumination.
Clear 60W bulbs provided around 120 lux of illumination while pearled 60W bulbs produced 101 lux.
By comparison, the best performing energy efficient light bulb, an 11W CFL made by General Electric and handed out free to Southern Electric customers, rated 79 lux. The worst performing 11W CFL, an Eveready, produced just 60 lux.
A Philips Softone 12W energy saving bulb also claimed to be equivalent to a 60W incandescent bulb, but it only produced 77 lux of illumination.
A spokesman for Philips said that its Softone Energy Saver bulbs met international standards and were intended to provide the equivalent light output of a frosted incandescent bulb, but our test shows it still failed to perform as well as a frosted bulb.
A spokesman for General Electric said all of their light bulbs were tested to meet international standards.
She added: “Our test results are then verified independently before our products are approved by the Energy Savings Trust.”
As part of the new European regulations, manufacturers will face tough new rules on labelling, and will be required to state their light emission in lumens as well as their power in Watts.
Syed Kamall, the Conservative MEP who has campaigned against European interference in traditional measures, said the new regulations would create confusion among consumers.
He said: "While lumens measure brightness, no one I have met understands these units."
Ferran Tarradellas Espuny, energy spokesman for the European Commission, said: "The regulation is setting clear rules on how equivalence claims with incandescent bulbs can be made on the packaging of efficient lamps."
A spokesman for the Trading Standards Institute, which regulates claims made about products sold in the UK, said it was not aware of any substantiated complaints about inaccurate labelling on low-energy bulbs.
A Defra spokesman said: "The EU is reviewing low energy light bulb labelling to make sure they are easily understood by consumers and will be monitoring the accuracy of the wattage claims."
How the energy saving bulbs compared to incandescent bulbs
Osram 60W (700 lumens) – 126 lux
Philips 60 W (700 lumens) -114 lux
Tesco 60W (700 lumens) – 122 lux
Maxim Pearl 60W pearled (no lumen info) – 101 lux
Energy Saving (all claim to be equivalent to 60W):
Philips 12W T60 Softone (610 lumens) – 77 lux
Southern Electric/GE 11W (610 lumens) – 79 lux
Tesco Greener living stick 11W (640 lumens) – 70 lux
Eveready Energy Saver 11W (no lumen info) – 60 lux
Osram Duluxstar 11W (600 lumens) – 67 lux
Source: www.telegraph.co.uk By: Victoria Ward
Their report advises that the bulbs should not be left on for extended periods, particularly near someone’s head, as they emit poisonous materials when switched on.
Peter Braun, who carried out the tests at the Berlin's Alab Laboratory, said: “For such carcinogenic substances it is important they are kept as far away as possible from the human environment.”
The bulbs are already widely used in the UK following EU direction to phase out traditional incandescent lighting by the end of this year.
But the German scientists claimed that several carcinogenic chemicals and toxins were released when the environmentally-friendly compact fluorescent lamps (CFLs) were switched on, including phenol, naphthalene and styrene.
Andreas Kirchner, of the Federation of German Engineers, said: “Electrical smog develops around these lamps.
“I, therefore, use them only very economically. They should not be used in unventilated areas and definitely not in the proximity of the head.”
British experts insisted that more research was needed and urged consumers not to panic.
Dr Michelle Bloor, senior lecturer in Environmental Science at Portsmouth University, told the Daily Express: “Further independent studies would need to be undertaken to back up the presented German research.”
The Department for the Environment insists the bulbs are safe, despite the fact that they contain small amounts of mercury which would leak out if the glass was broken.
Advice on its website states: “Energy efficient light bulbs are not a danger to the public.
“Although they contain mercury, limited at 5mg per lamp, it cannot escape from a lamp that is intact.
“In any case, the very small amount contained in an energy efficient bulb is unlikely to cause harm even if the lamp should be broken.”
The latest report follows claims by Abraham Haim, a professor of biology at Haifa University in Israel, that the bulbs could result in higher breast cancer rates if used late at night.
He said that the bluer light that CFLs emitted closely mimicked daylight, disrupting the body's production of the hormone melatonin more than older-style filament bulbs, which cast a yellower light.
The Migraine Action Association has warned that they could trigger migraines and skin care specialists have claimed that their intense light could exacerbate a range of existing skin problems.