Friday, August 21, 2009

Now candles are bad for you

How did our ancestors ever survive? But it's just speculation. No tests were done to see how they actually affected people

They can add a hint of romance to a meal or make taking a bath a real luxury. But scented candles can be bad for your health, say scientists. The smoke produced by many of them is laced with toxins linked to cancer, asthma and eczema. The odd candle is unlikely to do any harm, but we should avoid using them day after day in bathrooms and other poorly ventilated rooms, say the researchers.

The U.S. researchers burnt a range of candles in the laboratory and collected and tested the substances given off. This showed that those made of paraffin wax, the most common type, released potentially harmful amounts of chemicals such as toluene and benzene. Some of the pollutants have been linked to cancer, while others could trigger asthma attacks or skin complaints, the American Chemical Society's annual conference heard.

Most of those on sale in Britain, including many scented ones, are made of paraffin wax, a byproduct of the petroleum industry. Beeswax and soy candles, which are more expensive, were given a clean bill of health in the tests.

Researcher Dr Amid Hamidi, of South Carolina State University: 'An occasional paraffin candle and its emissions will not likely affect you. 'But lighting many paraffin candles every day for years or lighting them frequently in an unventilated bathroom around a tub, for example, may cause problems.'

Dr Noemi Eiser, of the British Lung Foundation, echoed the advice. She said: 'We would like to reassure people that occasional use of paraffin candles should not pose any risk to their lung health. 'However we would advise people to take sensible precautions when burning candles, such as opening a window to keep the room ventilated to minimise the amount of emissions breathed in.'

But Dr Joanna Owens, of Cancer Research UK, said: 'There is no direct evidence that everyday use of candles can affect our risk of developing cancer.' She said it more important to focus on the risk factors that there was hard evidence for, such as smoking, alcohol, obesity, unhealthy diets, inactivity and heavy sun exposure.

The British Candlemakers' Federation said an authoritative study two years ago concluded that candles, including those made of paraffin wax, did not pose a health risk.


Tiny magnets that help heal injuries could be used to treat cancer

Tiny magnets have been used to guide stem cells to repair injuries in a study that opens a new approach to targeted medicine. Research by British scientists has shown that nanomagnets consisting of stem cells “tagged” with microscopic particles containing iron, each of which is 2,000 times smaller than the thickness of a human hair, can be steered around the body using an external magnetic field.

The first study of the technique has shown that it can boost by five times the number of stem cells that reach the injured blood vessels of rats. The results also suggest that similar methods could be used in other branches of medicine, for example to guide chemotherapy drugs towards tumours while avoiding healthy tissue.

As the nanoparticles used in the experiment are already approved for medical use by the US Food and Drug Administration, human trials of the technology could potentially begin within three to five years, scientists said.

Mark Lythgoe, of University College London who led the study, said: “These particles are tiny: one nanometre is the distance that a fingernail grows in a second.” “It’s feasible that heart attacks and other vascular injuries could eventually be treated using regular injections of magnetised stem cells.

“The technology could be adapted to localise cells in other organs and provide a useful tool for the systemic injection of all manner of cell therapies. And it’s not just limited to cells – by focusing tagged antibodies or viruses using this method, cancerous tumours could be much more specifically targeted.”

In the study, published in the Journal of the American College of Cardiology: Cardiovascular Interventions , the team focused on a type of stem cell called endothelial progenitor cells, which have been shown to be important in vascular healing. Each cell was tagged with a “nanomagnet” about 50 nanometres in diameter, before these were injected into the rats. A magnetic field was then used to guide the tagged stem cells through the bloodstream until they reached an injured artery.

Panagiotis Kyrtatos, another member of the UCL team, said: “This research tackles one of the most critical challenges in the biomedical sciences today: ensuring the effective delivery and retention of cellular therapies to specific targets within the body. “The nanomagnets not only assist with the targeting but with the aid of MRI (magnetic resonance imaging) also allow us to observe how the cells behave once they’re injected.”

Professor Peter Weissberg, medical director of the British Heart Foundation, which helped to fund the study, said: “This encouraging research shows that nanomagnets could be used to help therapeutic stem cells reach specific areas of the body, particularly inside blood vessels where the blood is flowing fast and at high pressure. “We await further research to find out if, as well as increasing the chances of these cells getting to where they are needed, this strategy can actually speed up the repair process.”


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