Monday, May 11, 2009

The Toxin Gambit Part 1: Formaldehyde

We will be conducting a multiple-part series describing some of the vaccine constituents that many consider 'toxins' or just have what the actual chemical is, just plain wrong. The first part of our series will be dedicated to information regarding formaldehyde, what it is, why it is in vaccines and any health implications. So thank you to Valo for your suggestion.

For the purpose of this series, it is important to understand the metric scale, not so much the actual measurements but their relationship to one another. For example, if a microgram (mcg) is a grain of sand, then a milligram (mg) is a slice of American cheese, so a gram (g) is an average 5.5 year-old boy and a kilogram (kg) would be 7 H2 Hummers. Again, these aren't actual weights, volumes or measurements, but rather, their differences on a visual scale.

Formaldehyde is a naturally-occurring chemical that can also be synthesised. The chemical formula is CH2O and is also known as methanal (not to be confused with methanol), formal and methyl aldehyde. It is also not to be confused with formalin, which is an aqueous solution of formaldehyde. Numerous isomers of formaldehyde exist but they are not formaldehyde. It is used in the manufacture of resins that are then used for the production of pressed wood products, paper, textile fibres, adhesives and plastics (EPA 2009 and WHO 2006). Of course, those involved with the manufacturing of products with formaldehyde may sustain occupational exposure and subsequent pathologies (EPA, 2009 and WHO, 2006). Formaldehyde is also a by-product of tobacco smoke and combustion reactions from stoves, kerosene space heaters and automobiles (EPA 2009).

Naturally occurring sources of formaldehyde are found in plants, fruits, vegetables, animals (including humans) and seafood (Mason et al. 2004 and Inchem 1989). Table 14 of the Environmental Health Programme on Chemical Safety: Formaldehyde, and Table 95.2, Chapter 95: Formaldehyde, lists some commonly-consumed foods and their formaldehyde concentrations. (Clary and Sullivan 2001 and Inchem 1989). In a study of Shiitake mushrooms, investigators reported formaldehyde concentrations of 100-300 mg/kg; this wide variation is a result of a combination of analysis techniques, naturally-occurring formaldehyde and also possible contamination with exogenous formaldehyde (Mason et al. 2004).

Formaldehyde is a normal, essential human metabolite with a biological half-life of about 1.5 minutes (Clary and Sullivan 2001). It is endogenously produced and is involved with methylation reactions for and biosynthesis of some proteins and nucleic acids. It is also rapidly metabolised to formate and excreted in urine or to carbon dioxide and exhaled (WHO, 2006 and Clary and Sullivan 2001). Some common routes of exposure for exogenous formaldehyde include dermal, from occupational handling, inhalation, from occupational exposure and environment, oral via dietary intake and of course, intramuscularly or subcutaneously from vaccines. (Franks 2005, Clary and Sullivan 2001 and Inchem 1989).

Human normal blood concentrations of formaldehyde are 2.74 +/- 0.14 mg/L (Franks 2005). The average adult male (86 kg) in the U.S. has a blood volume of 5.8 litres; the average adult female (74 kg) has a blood volume of 5.0 litres and an average 2 month old infant (5 kg), 0.43 litres. So this translates to 15.1-16.7 mg of normal formaldehyde range in an adult male, 13.0-14.4 mg in an adult female and 1.1-1.2 mg in a 2 month-old infant which works out to be 0.22-0.24 mg/kg (CHOP 2008 and Franks 2005). Using the visual scale provided earlier for the infant, that would be a little more than 1 slice of American cheese/35 H2 Hummers.

Toxic levels of formaldehyde can induce a variety of illness from localised skin/respiratory tract irritation to cancer (Bosetti et al. 2008, Sundstrom et al. 2001 and Pandley et al. 2000). Inhalation of 1.0-2.0 parts per million or ppm (ppm=mg/kg) is considered mildly irritating, while 3.0 ppm causes moderate eye irritation although there is variation of sensitivity in individuals (Sundstrom et al. 2001 and Inchem 1989). Chronic inhalation studies on rats and mice have resulted in nasal cavity squamous cell carcinomas, when exposed to levels above 6-15 ppm (Bosetti et al. 2008 and Clary and Sullivan 2001). Formaldehyde toxicity resulting in death occurs in humans at a volume of about 60-90ml (Pandey 2000). The CDC conducted a survey of 'travel trailers' used for displaced people from hurricanes Katrina and Rita and found levels ranging from 0.003-0.59 ppm with an average of 0.077 ppm (CDC 2008). Thus far, only symptoms of local irritation have been reported (CDC 2008). A 2005 study of single-family homes in 3 cities detected an average of 0.17 ppm and 0.016-0.025 ppm in travel trailers (Weisel et al. 2005).

Formaldehyde in vaccines is left over from the production process, where it serves a couple of different functions, depending upon the type of antigens used. Essentially, it is used for killing cells and/or inactivating toxins. For example, the diphtheria-tetanus-acellular pertussis vaccine is a toxoid vaccine. The toxins produced by the bacteria are what causes illness in humans and what we need antibodies against. The addition of formaldehyde internally cross-links the toxin and also cross-links it to other toxins, effectively detoxifying to eliminate pathogenicity. Viral vaccines such as influenza and hepatitis A vaccines utilise formaldehyde to inactivate viral activity, allowing the recipient to produce antibodies to the antigens without pathogenicity (Aunins et al. 2000).

The actual amount in vaccines is minuscule, even when considering an infant that receives the full CDC schedule. If you look at this table, it contains a list of vaccines and their final formaldehyde content. Not included in this table is Pentacel which contains 0.005mg of formaldehyde. If all vaccines are given as per the CDC recommendation and separately, the most a 2 month old infant would receive is 0.1204 mg of formaldehyde or 120.4 mcg. Going back to what normal formaldehyde levels for a 5kg, 2-month old infant are 1.1-1.2 mg or 0.22-0.24mg/kg so the total formaldehyde exposure from vaccines would raise that to 1.22-1.32 mg or raises the baseline level by less than 1 grain of sand/35 Hummers. Put another way, the amount contained within a vaccine is more than 50 times less than what is in a pear.

Given what is known about human formaldehyde metabolism, excretion and toxic levels, along with what is actually in vaccines, we hope that this gives some perspective about the safety of the amount of formaldehyde that an infant would receive via vaccines. There is simply no valid argument, beyond the scope of fear-mongering that formaldehyde exposure from vaccines is implicated in any health problems, whatsoever.

Aunins JG, Lee AL, Volkin DB. Vaccine Production. In: Bronzino JD, ed. The Biomedical Engineering Handbook 2nd ed. Vol. 2. New York, NY: Springer Publishing; 2000. Accessed May 10, 2009:105-8—105-9.

Bosetti C, McLaughlin JK, Tarone RE, Pira E, La Vecchia C. Formaldehyde and cancer risk: a quantitative review of cohort studies through 2006 . Annals of Oncology. 2008; 19:29-43. Accessed May 10, 2009.

The Children's Hospital of Philadelphia (CHOP). Vaccine Education Center Web site. Accessed May 10, 2009.

Clary JJ and Sullivan, Jr. JB. Formaldehyde. In: Sullivan, Jr. JB and Krieger GR, eds. Clinical Environmental and Toxic Exposures. 2nd ed. Philadelphia, PA: Lippincott, Williams and Wilkins; 2001.,M1. Accessed May 10, 2009:1007-1008 and 1010.

Indoor Air Quality. U.S. Environmental Protection Agency (EPA) Web site. Accessed and link repaired Aug 1, 2012.

Franks SJ. A mathematical model for the absorption and metabolism of formaldehyde vapour by humans [abstract]. Toxicology and Applied Pharmacology. 2004; 206(3):309-320. Accessed May 10, 2009.

Environmental Health Criteria 89: Formaldehyde. International Programme on Chemical Safety (INCHEM) Web site. Accessed May 10, 2009.

Mason DJ, Sykes MD, Panton SW, Rippon EH. Determination of naturally-occurring formaldehyde in raw and cooked Shiitake mushrooms by spectrophotometry and liquid chromatography-mass spectrometry [abstract]. Food Additives and Contaminants. 2004; Nov;21(11):1071-1082. Accessed May 10, 2009.

Pandey CK, Agarwal A, Baronia A, Singh N. Toxicity of ingested formalin and its management [Abstract]. Human & Experimental Toxicology. 2000;Jun,19(6);360-366.$=citationsensor. Accessed May 10, 2009. PMID: 10962510.

CDC Final Report on Formaldehyde Levels in FEMA-Supplied Travel Trailers, Park Models, and Mobile Homes Web site July 2, 2008. Accessed May 10, 2009.

Weisel CP et al. Relationships of indoor, outdoor, and personal air (RIOPA). Part I. Collection methods and descriptive analyses [abstract]. Research Report (Health Effects Institute). 2005;Nov(130 Pt 1):1-107; discussion 109-127. Accessed May 10, 2009. PMID: 16454009.

IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. World Health Organization (WHO). Volume 88 Formaldehyde, 2-Butoxyethanol and 1-tert-Butxypropan-2-ol. 2006. Web site. Accessed May 10, 2009.

Thursday, May 7, 2009

Cochrane Collaboration on Influenza

I went to a talk given by Sir Iain Chalmers, cofounder and current director of the Cochrane Collaboration yesterday. He spoke about the various controlled trials that need to be performed to ensure that a new medicine is a) effective and b) not doing more harm than no treatment or previously used treatments. He was taking us through the history of treatments for pneumonia (for the longest time treated with blood letting, as late as 1903), treatment and prevention of diphtheria, and prevention of whooping cough and measles. I am hoping the James Lind Library or Public Health Department of Edinburgh University will publish the lecture eventually. For the moment, Evans, Thornton and Chalmers' book "Testing Treatments" , free for download at the James Lind Library is a suitable alternative. But since everyone is talking about the flu, Sir Iain also pointed to the Cochrane Collaboration's new page on all things infuenza and to Dr Tom Jefferson's pod cast that summarizes the findings of all Cochrane Reviews on influenza in a few minutes. Listen in - you may be surprised:

Special Podcast - summary of Cochrane Reviews on influenza

Play Now! | Download [mp3]