Consumer Health Digest #07-37

Your Weekly Update of News and Reviews
September 25, 2007


Consumer Health Digest is a free weekly e-mail newsletter edited by Stephen Barrett, M.D., and cosponsored by NCAHF and Quackwatch. It summarizes scientific reports; legislative developments; enforcement actions; news reports; Web site evaluations; recommended and nonrecommended books; and other information relevant to consumer protection and consumer decision-making.


New rules announced for ozone-producing air cleaners. The California Air Resources Board (CARB) has adopted the nation's first regulation to prohibit indoor air cleaners from emitting more than 0.050 parts per million of ozone. Ozone is the main ingredient of smog. Very low exposure is tolerable to humans, but at higher levels adverse health effects can result. Much research has led California to establish an outdoor ozone standard of 0.070 parts per million over an 8-hour period, and 0.090 parts per million over a one-hour period. Exposure beyond this level can lead to lung inflammation and impaired functioning, coughing, chest tightness, shortness of breath, worsening asthma symptoms, hospitalization due to respiratory issues, and potentially death. [California cleans up indoor air cleaners. CARB news release, Sept 27, 2007] The new regulation, which takes effect in 2009, will exempt industrial and commercial uses of ozone generators when people are not present.


Another study finds no neurologic damage from vaccines. It has been hypothesized that early exposure to thimerosal, a mercury-containing preservative used in vaccines and immune globulin preparations, is associated with neuropsychological deficits in children. However, a study of 1047 children who received these preparations between 1993 and 1998 has found no such association. [Thompson WW. Early thimerosal exposure and neuropsychological outcomes at 7 to 10 years. New England Journal of Medicine 357:1281-1292, 2007] Thimerosal was used in tiny amounts as a vaccine preservative. Even though exposure was slight, it was removed from most vaccines as an extra precautionary measure. An editorial accompanying the recent study traces the history of its use and the irresponsible way that it and certain other vaccines were criticized. [Offit PA. Thimerosal and vaccines: A cautionary tale. New England Journal of Medicine 357:1278-1279, 2007] The journal has posted the full text of both articles.


New review highlights neck manipulation dangers. Edzard Ernst, a leading analyst of "complementary medicine" research, has systematically reviewed reports of adverse effects of neck manipulation published between 2001 and 2006. In case reports or case series, more than 200 patients were suspected to have been seriously harmed. The most common serious effects were due to vertebral artery dissections. Two prospective reports suggested that relatively mild adverse effects occur in 30% to 61% of all patients. Most of the reported cases were treated by chiropractors. Survey data indicated that even serious adverse effects are rarely reported in the medical literature. After noting that "the effectiveness of spinal manipulation for most indications is less than convincing, Ernst concluded:

Spinal manipulation, particularly when performed on the upper spine, is frequently associated with mild to moderate adverse effects. It can also result in serious complications such as vertebral artery dissection followed by stroke. Currently, the incidence of such events is not known. In the interest of patient safety we should reconsider our policy towards the routine use of spinal manipulation.

The full text of the report is online. [Ernst E. Adverse effects of spinal manipulation: A systematic review. Journal of the Royal Society of medicine 100:330-338, 2007] Quackwatch has additional information about the risk of neck manipulation.


Dore treatment criticized. Dorothy Bishop, a psychology professor at Oxford University, has severely criticized the Dore treatment and the research that claims it works. [Bishop DVM. Curing dyslexia and attention-deficit hyperactivity disorder by training motor co-ordination: Miracle or myth? Journal of Paediatrics and Child Health 43:653–655, 2007] Bishop's report concludes:

Dore Achievement Centres are springing up world-wide with a mission to cure cerebellar developmental delay, thought to be the cause of dyslexia, attention-deficit hyperactivity disorder, dyspraxia and Asperger’s syndrome. Remarkable success is claimed for an exercise-based treatment that is designed to accelerate cerebellar development. Unfortunately, the published studies are seriously flawed. On measures where control data are available, there is no credible evidence of significant gains in literacy associated with this intervention. There are no published studies on efficacy with the clinical groups for whom the programme is advocated. It is important that family practitioners and paediatricians are aware that the claims made for this expensive treatment are misleading.

Dore's Web site states: "The Dore Programme of physical and mental exercise fine tunes and hard wires those parts of your skill learning centre so that learning becomes easy and automatic, giving you optimal performance in reading, handwriting, spelling, physical coordination, attention and memory." The exercises are said to "develop the cerebellum." The program, which is available at 50 "centers" worldwide, costs about $4,000, is said to take 12 to 18 months to complete. Wikipedia has a comprehensive report.


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This page was revised on September 29, 2007.