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Having medical reasons not to receive vaccines myself, I’m among those who mandatory vaccination for those who can be vaccinated would supposedly benefit the greatest.But I’m nonetheless very strongly against mandatory vaccination.Say you have 300 million magic pills you can give people that would give them 99% protection against disease, but a saboteur had been caught lacing them with poison, claiming almost 30,000 of them had enough poison to make them very sick, 500 had enough poison to permanently disable, and 200 had enough poison to kill people, but scattered the poisoned pills among the batch, and the poisoned pills don’t appear any different, and can only be detected by literally analyzing all the pills so one couldn’t identify which were tainted without destroying them. Then the perpetrator took one from the few remaining in the smallest pile, and soon convulsed and died.Would you offer these “magic pills” to people? Let alone force feed them? I certainly wouldn’t.And these figures are much more optimistic than the evidence for vaccination indicates, in terms of benefit vs. risk. Effectiveness of vaccines is typically from 70% to 95%, with some as low as offering only a 10% reduction in the odds of getting ill, such as the 2017–18 winter flu shot, which was the deadliest epidemic in recent history, to which about as many vaccinated as unvaccinated people succumbed. There is even considerable evidence that the very crude smallpox vaccine of the late 19th and early 20th century that gets the credit for the eradication of smallpox may have had no effectiveness at all, public health measures having actually done the work (see referenced data below).So if I couldn’t distribute those partially poisoned pills, how could I require people to assume a greater risk for lesser protection against diseases that are now very rare and were on the road to eradication due to improved nutrition and public health anyway (see below), and therefore are not going to come back to Dickensian levels, as many fear?Speaking of pills, many have been taken off the market by the FDA for causing far less harm than vaccines.So how consistent is it to force products on people that would be taken off the market for safety reasons when causing far less harm if they were over the counter medicines or nutritional supplements? Who is the FDA looking out for?It’s in the Hippocratic Oath: First Do No Harm. Vaccines unquestionably cause a lot of harm.Anti-vax sentiment didn’t just come out of thin air. A vast majority of “anti-vaxxers” are actually ex-vaxxers. Just ask them. These multitudes of parents who are reporting sharp declines in the health their formerly very healthy kids after vaccination cannot be merely imagining things. We need to listen to them, listen earnestly; and properly investigate the matter, at long last.Such an epidemic of “coincidence” is so far-fetched as to be incomprehensible. Over 50% of American children now have some sort of chronic health issues. It wasn’t like that when I was a kid. These concerns deserve more earnest attention ASAP.The vaccine injury register (VAERS) has reported an average of over 30,000 adverse reactions following vaccines, including over 600 permanent disabilities, and over 200 deaths per year since the mid 2000s. And this may be under-reported by a factor exceeding 200 (see below). I’ve read the data, and don’t believe any claims that only a small percentage of those injuries were actually vaccine injuries. If anything, it appears that at very best only a minuscule percentage were not. The stomach-turning facts are there, and the association is painfully obvious.Yes, it is true the only way to get a really good sense of the true extent of harm caused by vaccines would be a thorough and transparent (except for patient anonymity in public records) analysis of vaccination and medical records of millions of Americans. Any consistent association would give cause for consideration, and there is good reason to think would indicate the prevalence of vaccine injury is much, much worse than VAERS data. Which begs the question of why such an analysis hasn’t been done.Want to shut up anti-vaxxers? Do the study, already!It has long been suspected that vaccine injuries are grossly under-reported. Even government and associated agencies that are overwhelmingly staffed by individuals with pharmaceutical connections acknowledge the likelihood that vaccine injury is greatly under-reported, some CDC correspondence having estimated by a factor of 100. The most optimistic estimates indicate a factor of 10.To get a sense of the actual figures, an automated reporting study was performed from 2006 to 2009 in Massachusetts by Harvard Pilgrim Health Care, Inc., which flagged medical history events consistent with vaccine injury, such as acute anaphylactic reaction following vaccination. The report from the study can be found here: https://healthit.ahrq.gov/sites/default/files/docs/publication/r18hs017045-lazarus-final-report-2011.pdfThe results were shocking. Verbatim from the study report: “A total of 1.4 million vaccine doses (of 45 different vaccines) were given to 376,452 individuals. Of these doses, 35,570 possible reactions (2.6 percent of vaccinations) were identified.” That corresponds to history consistent with an adverse reaction per 39.4 vaccines (over 2.5%) and per 11 people who were vaccinated!That doesn’t look “extremely rare” to me. I could not see anything whatsoever faulty with the study methodology. And it stands to reason these reactions were serious enough to lead to a visit to the doctor or emergency room, or they would not have shown up in medical records.The study results indicate vaccine injuries are under-reported by a factor of 233, based on figures from the Vaccine Injury Adverse Event Reporting System VAERS Search VAERS Database and a reported figure of “at least 3,454,269,356 vaccine doses” from 2006 to 2017 in the US from a site that advocates vaccination.Vaccines Statistics and NumbersScaling up the VAERS figures from 2006–17 by an under-reporting rate of 233 gives us an estimate of 7,313,593 injuries, 148,314 disabilities, and 53,722 deaths due to vaccines per year: including on the order of 789,679 injuries, 10,504 disabilities, and 2,466 deaths due to measles vaccines alone in the US if serious events and measles vaccine events are under-reported at about the same rate as vaccine injuries, in general. That’s a very big “IF”, but I could not find such specific data associated with the Harvard Pilgrim study.By way of comparison, the US measles death rate was about 500 per year (slightly less than 1 death per 400,000 people per year) and disability rate was about 1000 per year prior to the introduction of the vaccine in the early 1960s; such victims having been mostly people who were in a poor state of health, rather than healthy children, as are a very large percentage of reported vaccine injury victims. That would be equivalent to about 800 deaths and 1600 disabilities scaled to today’s population had the measles death and disability rates remained the same -- though they had been decreasing, as a general trend, and would likely be a considerably lower by now, had the trend continued.I highlighted measles because “measles outbreaks” on the order of dozens of cases from which all have fully recovered are all over the news in a deliberate and largely successful campaign to incite unwarranted hysteria to convince more people to vaccinate at the time of this edit.Here’s an image of the spreadsheet I generated to make such calculations (if it’s hard to see, click to magnify for a clearer view):So this evidence begs the question: What is causing more harm, the treatment or the disease?Those figures are in line with my personal observations. About 1 in 50 people I know have recently reported some sort of significant vaccine injury to themselves or a family member. It’s a small sample size, but that would be equivalent to 6 million among the US population of about 300 million. Just about right in line with the automated reporting study projections.There are volumes of anecdotal evidence as well, which is remarkably consistent (consistency and independence being the best gauges of the veracity of anecdotal evidence). An anonymous (to keep their job safe from a witch hunt, so powerful vaccine dogma is within the medical profession) ER nurse who noticed a lot of non-accident emergency admissions of people who had just been vaccinated reported that “he” was the only among a staff of over 300, possibly as many as 500, who reported such admissions; and not even that, noticed that doctors actively suppressed reporting of such incidents, reporting them as “of unknown cause”. ER Nurse Shares His Experiences With Vaccine ReactionsAlso, chronic illnesses and mental impairments were much, much less common when I was a kid and there were about 1/3 as many vaccines administered later in life. In my schools we had a few “special ed” kids, not entire classes. Now such conditions have reached a level that strains the very resources of schools:February 2020: Injured Kids, Society Costs • Children's Health DefenseI don’t know how much effect the proliferation of vaccinations has to do with the recent proliferation of chronic health issues and mental impairments in children, as there are other very plausible causes, such as Roundup in commercially grown (as opposed to organic) food, EMF exposure from mobile phones and wireless devices (5G could wreak havoc on health, so the worse may be yet to come), and use of high-fructose corn syrup instead of sugar. But a well controlled survey of of 405 vaccinated and 261 unvaccinated kids within a local population strongly suggests such a connection; though again it was not controlled for diet:Pilot comparative study on the health of vaccinated and unvaccinated 6- to 12- year old U.S. childrenIn that survey the vaccinated children were found to have a 19% (about 1 in 5, 44.0% to 24.9%) greater chance of having been diagnosed with chronic health issues than the unvaccinated children, 4.7 times the rates of autism and learning disabilities (4.7% to 1.0% for each), and over 3 times the rates of neuro-developmental disorders (10.1 % to 3.1%) and allergies (22.6% to 6.9%) as the unvaccinated kids.Perhaps more surprisingly, the vaccinated children had a 20% higher rate of sick visits to their doctor within the past year (36% to 16% - what does this imply about susceptibility to novel infections, such as the coronavirus?) and a 5 times higher rate (5% greater chance) of pneumonia (6.4% to 1.2%) than the unvaccinated children. But the sick visits could also have been due to a greater inclination to treat illness at home, so I’d take that one with a big pinch of salt; though the ratio of sick visits far exceeded the ratio of routine checkups. Still, the results are pretty consistent among neurological issues.Every time an isolated outbreak of a few measles cases occurs, from which all fully recover, there’s a big hue and cry blaming “anti-vaxxers”. Why so much alarm about those few instances, with so much less concern for multitudes of vaccine injuries, including many lifelong serious disabilities and even deaths, especially when vaccinated people may even be less healthy in general?It seems way out of proportion. I thought the idea was to maximize health and minimize death and disability.I think in order to justify making a treatment mandatory, it has to be proven overwhelmingly safe beyond a reasonable doubt. There’s not only reason to doubt the safety of vaccines, but overwhelming evidence they’re unsafe for many, many people, and we’re still not able to reliably determine who until it’s too late.Again, the only way to really tell whether or not vaccines have a net benefit at all would be to assess overall health outcomes of vaccinated and unvaccinated people, accounting for all outcomes. If, for example, diseases or vaccines increase the odds of mental impairments, it stands to reason they could also impact matters such as accidents, violent crime, and suicide, which are among the leading causes of death of young people, especially teens.Enough of the bad news about vaccine injuries. Here’s the good news: if people don’t vaccinate, massive epidemics are highly unlikely to come back, as long as we maintain good public health and nutrition.The most stunning proof of this is overwhelmingly unvaccinated Leicester, England having virtually eradicated smallpox with less than 20% of its citizens vaccinated from about 1885 through the 1940s, no smallpox deaths having occurred most years when almost nobody was vaccinated, and with only 2 known smallpox deaths from 1908 to 1948.The doom and gloom predictions of massive, deadly smallpox epidemics in predominately unvaccinated Leicester never came to pass.Here’s the data from 1838 to 1910, when the greatest changes in the vaccine coverage and smallpox death rate occurred in Leicester. If it’s hard to see, click to magnify for a clearer view:The citizens literally revolted against mandatory vaccination after the worst smallpox epidemic on record killed multitudes of their about 90% vaccinated people in the early 1870s, along with many killed by the vaccine itself. Yes, the worst epidemic occurred when the city had the greatest “vaccine coverage”!They elected people who opposed mandatory vaccination, and did not enforce the law, and almost nobody in Leicester vaccinated for decades. They used sanitation, nutrition, and quarantine with more success than other English communities; who also eventually incorporated the Leicester sanitation measures, after which their measles death rates sharply declined as well.The success of Leicester in eradicating smallpox while remaining predominately unvaccinated led to the repeal of mandatory vaccination laws in the UK.A majority of people are quite unaware of this. But more people are finding out, as sales of the book linked below have skyrocketed in response to recent events as of this edit in response to the heightened censorship campaign against information that calls vaccines into question.History seems to be repeating itself, as untold multitudes of parents are noticing sharp declines in the health of their formerly very healthy kids after theirs umpteenth vaccines!Here’s the reference for this info, in which the primary data is extensively referenced (and I may add in later edits):Dissolving Illusions: Disease, Vaccines, and The Forgotten History: Suzanne Humphries MD, Roman BystrianykThe book also shows how polio vaccination may well have had less to do with the “disappearance” of the disease than phasing out of DDT and simple reclassification of the cases. Such paralytic conditions are still rampant in India, which is predominately vaccinated, and DDT is still on the shelves.More proof is in the mortality rate data for communicable diseases, such as this referenced graph, which you can view more clearly by clicking on it to magnify it:Surprised? I certainly was when I first saw this, having believed, as most do and current government web sites spin the data to imply, that there were massive epidemics, vaccines came into use, and all of a sudden the diseases went away. That was obviously not the case, not by a long shot.But then, governments are largely staffed (especially at the top) and medical programs funded by pharmaceutical companies who understandably want to believe in them, even aside from any profit motive. Is it reasonable to expect even-handedness in government literature and medical training when the hands of vaccine manufacturers are all over it?Many doctors who have changed their minds have reported that it took several instances of very obvious and severe vaccine injuries to shake their faith. And when they reported such instances invariably came under fire. Many doctors know, but few dare to go public for fear of jeopardizing their careers. Here’s the story of one courageous doctor who did go public, one of the authors of the book cited above, and the Spanish inquisition-like opposition she dealt with:http://drsuzanne.net/wp-content/uploads/2011/11/author-intro-Suzanne-Humphries.pdfMedicine evolves. Not that long ago medical professionals forced homosexuals and people with mental health issues to undergo torturous electric shock treatment, which disabled and killed some, to “cure” them “for the common good”. It may seem strange now, but most really believed they were doing a great service to humanity. Anyone who spoke out against it was “anti-science”, an “idiot”, a “quack” (if a medical professional), “ignorant”, “dangerous”, or whatever. Does any of this language look familiar?Back to the data, note which disease killed people at the highest rate, scarlet fever, and how it was virtually eradicated with no vaccination program at all. Other diseases such as typhus have gone the same way with no vaccination programs. Note how measles and whooping cough (for which current vaccines are among the least effective) had already decreased by over 99% from their Victorian era levels prior to vaccination to less than 1 death per 100,000 people per year, and they were still on the decline. Also note how initiation of the vaccination program had little effect on the death rate trend for diphtheria, as well, the death rate corresponding more strongly to conditions affecting public health, such as wars and their aftermath and economic conditions.Yes, 19th century graveyards have lots of tombstones of young kids. But think of the filth, squalid living conditions, and malnutrition back then. Even the rich didn’t have clean water or even bathe. Surgeons in the US Civil War didn’t even properly wash their surgical instruments.The death rate trends for virtually all communicable diseases have been about the same, going to near 0, regardless of when or even if vaccination programs began. Natural host resistance due to decades of improved nutrition and public health has won out, as evident from the virtual eradication of diseases for which there have been no vaccination programs at all.The one exception is poliomyelitis, which, counter to the decline of infectious diseases in general, increased proportionally to the use of persistent (i.e. remain in body fat for some time) agricultural pesticides which kill insects by paralysis in the mid 20th century, such as calcium arsenate and lead arsenate (yep, a compound of lead and arsenic) in the early 1940s, and benzene hexachloride (BHC) and the all-familar DDT in the late 1904s and early 1950s. Furthermore, the rate of poliomyelitis declined concurrently with the decreased production of those pesticides (which also happened to be near the time the vaccine was introduced, after which time those pesticides were primarily exported), the peaks and valleys following those of the pesticide consistently.Reference: Graphic documentation re polio epidemiology and physiology.But poliomyelitis was not epidemic among some well fed indigenous populations who lived in sunny, warm climates, such as the South American Xavante tribe, who had nearly 100% rates of infection of all 3 major polio viruses but according to the cited study “little or no indications” of poliomyelitis (the paralytic disease), while American service workers in the area did get poliomyelitis.Primary reference: J.V. Neel et al., “Studies on the Xavante Indians of the Brazilian Mato Grosso,” American Journal of Human Genetics, vol. 15, March 1964, pp. 52-140https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1932461/pdf/ajhg00547-0066.pdfDiscussion of the infection rates and absence of the paralytic disease is on pages 122 and 128 of the PDF (pages 72 and 78 of the paper).But when this came to light in the 1960s researchers did not make the connection with environmental toxins and processed, nutrient-deficient junk foods to which the indigenous populations had not been exposed. But what happened when these people mixed with white people? Voila! They got poliomyelitis. These indigenous people thought they got the diseases such as poliomylitis from contact with white people; but evidently it was the unhealthy practices of white people that got them ill. In this reference, which is a very, very tough read, a doctor who observed the effects of vaccination and connected the dots describes the heart-breaking and indeed horrifying experiences that led him to do an about-face on vaccination: Dr Kalokerinos interviewFurthermore, viral illness does not typically present as paralytic at its onset, whereas the above pesticides kill by paralysis.So that begs the question: is it not one’s right to render polio harmless with healthy lifestyle practices, rather than vaccines that could be injurious or even make them more susceptible to other paralytic conditions, such as transverse myelitis and acute flaccid paralysis, which had been diagnosed as “poliomyelitis” prior to advent of the vaccine, and have increased in incidence after the introduction of vaccination for polio?Acute flaccid paralysis, a condition that would have been diagnosed as “poliomyelitis” prior to introduction of the vaccine, and is even more deadly, was very rare prior to the polio vaccination program, but now kills over 40,000 per year in India, where DDT is still in use at the time of this edit (2019 July). In fact, there is a call for ending polio vaccination there for that very reason, and the fact that viral polio itself has virtually been eradicated: Polio programme: let us declare victory and move on.So why should we expect major epidemics to ensue if people who don’t want vaccines aren’t vaccinated, or even if vaccination is discontinued altogether, for that matter?Are all those at least tens of thousands of vaccine injuries, including numerous severe disabilities and deaths, and possibly on the order of a couple hundred times more than we know, even worth it any more?It may even be time to declare victory, give vaccines a fist bump and seat on the bench, and have them at the ready in case outbreaks occur, which the data suggests are overwhelmingly likely to remain isolated and very small in scale, just like all recent outbreaks in developed nations.But that said, I respect anybody’s choice to vaccinate if they wish, and am not an “anti-vaxxer”; however unconvinced I am of their net benefit for people with healthy immune systems, except perhaps in case of outbreaks. Your body, your choice.There is one more matter that it is important to address, and that is social stability considerations. What if vaccination became mandatory for all but people like me who have clear medical reasons not to be vaccinated? As it is, with vaccination being by and large voluntary, there’s quite a bit of anti-vaccine sentiment and outcry against the “holocaust” (in the words of RFK Jr.) of vaccine injury. Which has risen in proportion to the mass media efforts to censor it.What can we expect to become of anti-vax sentiment if more and more people or their children are seriously injured, or even permanently disabled or killed by vaccines that are forced upon them? Anti-vax sentiment will inevitably increase to a fever pitch, and get far, far more vehement, maybe even violent. Things could well get very, very ugly.Just like it did in Leicester in the late 19th century.Those who do not know history are doomed to repeat it.I’d much rather have people do what they want, and let the results sort things out organically. And as long as decent public health is maintained and people are well fed, I fully expect the trend will continue toward less vaccination… and overall public health will improve, as less people are harmed by vaccines, and outbreaks of disease remain very rare, isolated, and easily contained.

The controversy centres on the fact that amalgams contain mercury. In high enough concentrations, mercury is toxic.Some make the point that amalgams make people sick from allergies to neurotoxicity to a whole host of other systemic alimentsThere has been a great deal of bunk science done on amalgam.I will simply post some key concensus documents which also reference reputable science with respect to the use of dental amalgam.the overall consensus is that amalgam has been used for more than 200 years and except for a small number of patients who might have sensitivities to it, it is safe.Another key point made across the documents is that wholsesale removal of amalgam filling from patient is not indicated.Statement on Dental AmalgamStatement on Dental AmalgamFor dental patients: Please visit the ADA’s MouthHealthy website for information about amalgam and silver-colored fillings.Dental amalgam is considered a safe, affordable and durable material that has been used to restore the teeth of more than 100 million Americans. It contains a mixture of metals such as silver, copper and tin, in addition to mercury, which binds these components into a hard, stable and safe substance. Dental amalgam has been studied and reviewed extensively, and has established a record of safety and effectiveness.The FDI World Dental Federation and the World Health Organization concluded in a 1997 consensus statementi: “No controlled studies have been published demonstrating systemic adverse effects from amalgam restorations.” Another conclusion of the report stated that, aside from rare instances of local side effects of allergic reactions, “the small amount of mercury released from amalgam restorations, especially during placement and removal, has not been shown to cause any … adverse health effects.”In 1998, the ADA’s Council on Scientific Affairsii published its first major review of the scientific literature on dental amalgam which concluded that “based on available scientific information, amalgam continues to be a safe and effective restorative material.” The Council’s report also stated, “There currently appears to be no justification for discontinuing the use of dental amalgam.”In an articleiii published in the February 1999 issue of the Journal of the American Dental Association, researchers report finding “no significant association of Alzheimer’s Disease with the number, surface area or history of having dental amalgam restorations” and “no statistically significant differences in brain mercury levels between subjects with Alzheimer’s Disease and control subjects.”A 2003 paper published in the New England Journal of Medicineiv states, “Patients who have questions about the potential relation between mercury and degenerative diseases can be assured that the available evidence shows no connection.”In 2004, an expert panel reviewed the peer-reviewed, scientific literature published from 1996 to December 2003 on potential adverse human health effects caused by dental amalgam and published a report. The review was conducted by the Life Sciences Research Office (LSRO) and funded by the National Institutes of Dental and Craniofacial Research, National Institutes of Health and the Centers for Devices and Radiological Health, U.S. Food and Drug Administration (FDA). The resulting report states that, “The current data are insufficient to support an association between mercury release from dental amalgam and the various complaints that have been attributed to this restoration material. These complaints are broad and nonspecific compared to the well-defined set of effects that have been documented for occupational and accidental elemental mercury exposures. Individuals with dental amalgam-attributed complaints had neither elevated urinary mercury nor increased prevalence of hypersensitivity to dental amalgam or mercury when compared with controls.” The full report is available from LSRO (The Life Sciences Research Office (LSRO)). A summary of the review is published in Toxicological Reviews.vIn 2006, the Journal of the American Medical Association (JAMA) and Environmental Health Perspectives published the results of two independent clinical trials designed to examine the effects of mercury release from amalgam on the central and peripheral nervous systems and kidney function. The authors concluded that “there were no statistically significant differences in adverse neuropsychological or renal effects observed over the 5-year period in children whose caries are restored using dental amalgam or composite materials”;vi,vii and “children who received dental restorative treatment with amalgam did not, on average, have statistically significant differences in neurobehavioral assessments or in nerve conduction velocity when compared with children who received resin composite materials without amalgam. These findings, combined with the trend of higher treatment need later among those receiving composite, suggest that amalgam should remain a viable dental restorative option for children.”viiiIn May 2008, a Scientific Committee of the European Commission addressed safety concerns for patients, professionals and the use of alternative restorative materials.ix The committee concluded that dental amalgams are effective and safe, both for patients and dental personnel and also noted that alternative materials are not without clinical limitations and toxicological hazards.The ADA Council on Scientific Affairs prepared a comprehensive literature review (PDF) on amalgam safety that summarized the state of the evidence for amalgam safety (from January 2004 to June 2010). Based on the results of this review, the Council reaffirmed at its July 2009 meeting that the scientific evidence supports the position that amalgam is a valuable, viable and safe choice for dental patients.On July 28, 2009, the U.S. Food and Drug Administration (FDA) issued its final rule on encapsulated dental amalgam classifying amalgam and its component parts, elemental mercury and powder alloy, as a class II medical device. Previously there was no classification for encapsulated amalgam, and dental mercury (class I) and alloy (class II) were classified separately. This new regulation places encapsulated amalgam in the same class of devices as most other restorative materials, including composite and gold fillings. At the same time, the FDA also reaffirmed the agency’s position that the material is a safe and effective restorative option for patients.The CSA supports ongoing research on the safety of existing dental materials and in the development of new materials, and continues to believe that amalgam is a valuable, viable and safe choice for dental patients.Referencesi. FDI Policy Statement/WHO Consensus Statement on Dental Amalgam. September 1997. Accessed October 9, 2013.ii. ADA Council on Scientific Affairs. Dental Amalgam: Update on Safety Concerns. J Am Dent Assoc. 1998;129:494-503. Accessed October 9, 2013.iii. Saxe SR, Wekstein MW, Kryscio RJ, et al. Alzheimer’s disease, dental amalgam and mercury. J Am Dent Assoc. 1999;130(2):191-9. Accessed October 9, 2013. (Abstract)iv. Clarkson TW, Magos L, Myers GJ. The toxicology of mercury – Current exposures and clinical manifestations. N Engl J Med. 2003;349:1731-7.v. Brownawell AM, Berent S, Brent RL, et al. The potential adverse health effects of dental amalgam. Toxicol Rev 2005;24(1):1-10. Accessed October 9, 2013. (Abstract)vi. Bellinger DC, Trachtenberg F, Barregard L, et al. Neuropsychological and renal effects of dental amalgam in children: a randomized clinical trial. JAMA 2006;295(15):1775-83. Accessed October 9, 2013. (Abstract)vii. Bellinger DC, Daniel D, Trachtenberg F, Tavares M, McKinlay S. Dental amalgam restorations and children’s neuropsychological function: the New England Children’s Amalgam Trial. Environ Health Perspect 2007;115(3):443-6. Accessed October 9, 2013.viii. DeRouen TA, Martin MD, Leroux BG, et al. Neurobehavioral effects of dental amalgam in children: a randomized clinical trial. JAMA 2006;295(15):1784-92. Accessed October 9, 2013.ix. European Commission: Scientific Committee on Emerging and Newly Identified Health Risks. The Safety of Dental Amalgam and Alternative Dental Restoration Materials for Patients and Users May 6, 2008. Accessed October 9, 2013.Another link from the Government of Canada which looks at amalgam safety and delves into amalgam policies from other countries:The Safety of Dental AmalgamStatement from the Canadian Dental Association on amalgam:https://www.cda-adc.ca/_files/position_statements/amalgam.pdfA paper on this controversy:The Dental Amalgam Toxicity Fear: A Myth or ActualityToxicology InternationalMedknow PublicationsThe Dental Amalgam Toxicity Fear: A Myth or ActualityMonika Rathore, Archana Singh, and Vandana A. PantAdditional article informationAbstractAmalgam has been used in dentistry since about 150 years and is still being used due to its low cost, ease of application, strength, durability, and bacteriostatic effect. When aesthetics is not a concern it can be used in individuals of all ages, in stress bearing areas, foundation for cast-metal and ceramic restorations and poor oral hygiene conditions. Besides all, it has other advantages like if placed under ideal conditions, it is more durable and long lasting and least technique sensitive of all restorative materials, but, concern has been raised that amalgam causes mercury toxicity. Mercury is found in the earth's crust and is ubiquitous in the environment, so even without amalgam restorations everyone is exposed to small but measurable amount of mercury in blood and urine. Dental amalgam restorations may raise these levels slightly, but this has no practical or clinical significance. The main exposure to mercury from dental amalgam occurs during placement or removal of restoration in the tooth. Once the reaction is complete less amount of mercury is released, and that is far below the current health standard. Though amalgam is capable of producing delayed hypersensitivity reactions in some individuals, if the recommended mercury hygiene procedures are followed the risks of adverse health effects could be minimized. For this review the electronic databases and PubMed were used as data sources and have been evaluated to produce the facts regarding amalgam's safety and toxicity.Keywords: Amalgam, mercury, myth, restoration, safety, tooth, toxicityINTRODUCTIONAmalgam, an alloy of mercury (Hg), is an excellent and versatile dental restorative material. It has been used in dentistry since 150 years due to its low cost, ease of application, strength, durability, and bacteriostatic effects.[1] Popularity of amalgam as restorative material is decreasing these days due to concerns about detrimental health effects, environmental pollution, and aesthetics.[2] The metallic colour of amalgam does not blend with the natural tooth colour so patients and professionals preferred tooth-coloured restorative material for cavity filling in carious teeth for better aesthetics. Researchers agree that amalgam restorations leach mercury into the mouth, but consistent findings are not available to report whether it has any significant health risk.[3] In this review, an attempt has been made to summarize that there is no convincing evidences pointed out to adverse health effects due to dental amalgam restorations and can be used as a preferred restorative material where aesthetics is not a concern.Amalgam composition and historical backgroundAmalgam consists of an alloy of silver, copper, tin, and zinc combined with mercury. Unreacted alloy particles of silver-tin are considered as gamma phase. These particles combine with mercury and form a matrix consisting of gamma-1(Ag2Hg3) and gamma-2 phases. (Sn7-8Hg). The gamma-2 phase is responsible for early fracture and failure of amalgam restorations. Hence, copper was introduced to avoid gamma-2 phase, replacing the tin-mercury phase with a copper-tin phase (Cu5Sn5).[4] Louis Regnart, known as the ‘Father of Amalgam’, improved on boiled mineral cement by adding mercury, which greatly reduced the high temperature originally needed to pour the cement on to a tooth. In 1890s GV Black gave a formula for dental amalgam that provided clinically acceptable performance and remained unchanged virtually for 70 years. In 1959, Dr Wilmer Eames[5] promoted low mercury-to-alloy mixing ratio. The mercury-to-amalgam ratio, dropped from 8:5 to 1:1. The formula was again changed in 1963, when amalgam consisting of a high-copper dispersion alloy was introduced.[6] It was later discovered that the improved strength of the amalgam was a result of the additional copper forming a copper–tin phase that was less susceptible to corrosion than the tin–mercury phase in the earlier amalgam.[7]Modern amalgams are produced from precapsulated (preproportioned) alloy consisting of 42% to 45% mercury by weight. These are convenient to use and provide some degree of assurance that the material has not been not contaminated before use or spilled before mixing.[8]Amalgam controversy and amalgam warIn the year 1843, the American Society of Dental Surgeons (ASDS), founded in New York City, declared use of amalgam to be malpractice because of the fear of mercury poisoning in patients and dentists and forced all its members to sign a pledge to abstain from using it.[9] It was the beginning of the amalgam war.[10] Because of its stance against amalgam, membership in the American Society of Dental Surgeons declined, and due to the loss of members, the organization was disbanded in 1856 thus resulting in the end of the amalgam war. In 1859, the American Dental Association (ADA) was founded and it did not forbid use of amalgam.[11] The ADA position on the safety of amalgam has remained consistent since its foundation. In 1920s inferences were made that mercury was not tightly bound in amalgam so its use was discouraged. In 1991, National Institute of Health-National Institute for Dental Research (NIH-NIDR) and FDA concluded that there was no basis for claims that amalgam was a significant health hazard,[12] but claims of amalgam hazards continued to be published in non-scientific journals, and occasionally in scientific journals.Mercury exposure from amalgam restorationsMercury is ubiquitous in environment and humans are routinely exposed via air, water, and food.[8] Exposure to mercury in human individuals with amalgam restoration occurs during the placement or removal of dental restorations. Once the reaction is complete, less amount of mercury is released, that is far below the current health standard.[8] The exposure to mercury from restoration depends on the number and size of restoration, composition, chewing habits, food texture, grinding, brushing of teeth, and many other physiological factors. As a vapour, metallic mercury could be inhaled and absorbed through the alveoli in the lungs at 80% efficiency. It is the main route of entry of mercury into the human body, whereas the absorption of metallic mercury through skin or via the gastrointestinal tract is very poor.[8] The organic compounds of mercury such as methyl mercury are readily absorbed by many organisms and accumulate as it passes into food chain. Research on monkeys had shown that mercury released from amalgam restorations is absorbed and accumulated in various organs such as kidney, brain, lung, liver, gastro-intestinal tract, and the exocrine glands.[13] The organic form of mercury was also found to have crossed the placental barrier in pregnant rats[14] and proven to cross the gastrointestinal mucosa when amalgam particles are swallowed at the time of amalgam insertion or during removal of old amalgam fillings,[15] whereas the inorganic form of Mercury ions (Hg+2) circulate into the blood stream but hardly cross the blood–brain barrier and placental barrier.Mercury does not collect irreversibly in human tissues. The average half life of mercury is 55 days for transport through the body to the point of excretion. Thus mercury that came into the body years ago may no longer be present in the body.[8]Diagnostic methods to detect levels of mercury in bodyToxicity from mercury could occur through exposure to organic, inorganic, and elemental forms of mercury. According to decreasing toxicity of mercury it is classified as organomercury (methyl and ethyl mercury), mercury vapour, and inorganic mercury. Various diagnostic methods exist to detect the level of mercury in body, including tests for blood, urine, stool, saliva, hair analysis, and others. These tests may determine if mercury is in the body and/or if it is being excreted. A study[16] conducted by measuring the intraoral vapour levels over a 24-h period in patients with at least nine amalgam restorations showed that the average daily dose of inhaled mercury vapour was 1.7 μg (range from 0.4 to 4.4 μg), which is approximately 1% of the threshold limit value of 300 to 500 μg/day established by WHO, based on a maximum allowable environmental level of 50 μg/day in the workplace. According to Berdouses et al.[17] mercury exposure from amalgam can be greatly increased by personal habits such as, chewing and brushing.Berglund,[18] in 1993, determined the daily release of mercury vapour from amalgam restorations made of alloys of the same types and batches as those used in the in vitro part of the study. He carried out a series of measurements on each of eight subjects before and after amalgam therapy and found that none of the subjects were occupationally exposed to mercury. The amalgam therapy, that is, from 3 to 6 occlusal amalgam surfaces and from 3 to 10 surfaces in total-had very little influence on the intraoral release of mercury vapour, regardless of amalgam type used, effects was not found on mercury levels in urine and saliva. Rapid and reliable detection of mercury in blood and urine resulting from environmental and occupational exposure may be carried out by using atomic fluorescence spectrophotometry.[19] Measurements of total mercury in the urine tend to reflect inorganic mercury exposure and total mercury levels in whole blood are more indicative of methyl mercury exposure. Commonly two types of urine tests have been used in which one is the unprovoked mercury test that does not use a pharmaceutical mercury chelator and only reflects the amount of mercury the body naturally removes via the urine. The other is the urine mercury challenge (provoked) test, which uses a pharmaceutical chelator to remove the mercury captured via the kidneys/urine pathway. Both methylmercury and inorganic mercury can also be measured in breast milk. The relative proportions of these species depend on the frequency of fish consumption, dental amalgam status, and occupational exposures. In a study for comparison of hair, nails, and urine for biological monitoring of low level inorganic mercury exposure in dental workers, the data suggested that urine mercury remains the most practical and sensitive means of monitoring low level occupational exposure to inorganic mercury.[20]Various related studiesIn this review electronic databases and PubMed have been used for data sources and articles from peer reviewed journals and various organizations including WHO (1991), the Agency for Toxic Substances and Disease Registry (ATSDR) (1999), US Environmental Protection Agency (EPA,1997), the National Research Council (NRC) (2000), the Institute of Medicine (2001; 2004) and Life Science Research Office (LSRO) (2004) have been evaluated to investigate the biochemical, behavioural, and/or toxicological effects resulting from exposure to amalgam, mercury vapour (HgO), inorganic mercury (Hg2+), or organic mercury (methyl and ethyl mercury). The LSRO search was limited to in vivo studies on humans relevant to amalgam and biochemical, behavioural and/or toxicological effects as health effects in laboratory animals do not reliably predict health effects in humans.Effects of prenatal mercury exposureNonionized mercury is capable of crossing through lipid layers at membrane barriers of the brain and placenta, is oxidised within these tissues and is slowly removed. This fact has become the basis for claims of neuromuscular problems in patients with amalgam restorations.[8] Removing these restorations do not eliminate exposure to mercury. Maternal amalgam restoration results in in utero exposure to low levels of elemental mercury. There is no evidence that exposure to mercury has been associated with any adverse pregnancy outcomes or health effects in the newborn and infants. In a prospective study consisting of 72 pregnant women, it was found that the number and surface areas of amalgam restorations positively influenced the concentration of mercury in amniotic fluid. The levels of mercury detected in amniotic fluid were low and no adverse outcomes were observed during the pregnancy or in the newborns.[21] Blood samples obtained from umbilical cord had no significant mercury levels considered to be hazardous for neurodevelopmental effects in children using the EPA reference dose (5.8 μg/L in cord blood).[22] To find co-relation between mercury exposure from amalgam restorations placed during pregnancy and low-birth weight 1,117 women with low birth weight infants were compared with random sample of 4,468 women who gave birth to infants with normal birth weight. Women (4.9%) had at least one amalgam restoration placed during pregnancy. These women were not at greater risk for a low birth weight infant and neither were women who had 4 to 11 amalgam restorations placed.[23] In a study conducted by Daniels[24] 90% of the women received dental care during pregnancy. Having more restorations placed at time of conception did not negatively affect pregnancy or birth outcome. Mean umbilical cord mercury concentration was slightly higher in women who had dental care. However, cord mercury concentrations did not differ significantly among mothers in relation to amalgam restoration during pregnancy or by the number of amalgams in place prior to pregnancy. Overall, amalgam restorations were not associated with negative birth outcomes or delayed language development. They stated that amalgam restorations in girls and women of reproductive age should be used with caution to avoid prenatal mercury exposure, although there were no adverse effects seen.Health effects of amalgam in childrenThe Children's Amalgam Trial is a randomized trial, to address potential impact of mercury from amalgam restorations on neuropsychological and renal function in children. Bellinger et al.[25] conducted a study on 534 New England children, aged 6–10 years for 5 years. All subjects were in need of at least two posterior occlusal restorations. Participants were randomized to receive either amalgam or composite restoration at baseline and at subsequent visits. The primary endpoint was to assess the 5-year change in IQ scores. Secondary endpoints included measures of other neuropsychological assessments and renal functioning. In the 5-year follow-up period the investigators conducted multiple assessments of IQ score, memory index, and urinary albumin. No statistically significant differences were reported in neuropsychological or renal effects observed in the children who had amalgam restorations compared to those with composite restorations.In another study, authors have concluded that there was no difference in the neuropsychological function of the children who received amalgam restorations compared to the children with composite restorations.[26] A dose-effect analysis of children's exposure to amalgam and neuropsychological function was also evaluated in the children's amalgam trial. The authors examined a sample of children with substantial unmet dental needs using a dose–effect analysis. There was no significant association between neuropsychological outcomes and mercury exposure. The authors concluded that there appeared to be no detectable adverse neuropsychological outcomes in children attributable to the use of amalgam restorations.[27] The relation between amalgam and the psychosocial status of children was also assessed as a part of the New England Children's Amalgam Trial (NECAT). The two groups of children were examined for psychosocial outcomes. It was carried out using both a parent-completed “Child Behaviour Checklist” and children's self-reports and concluded that there was no evidence associated with adverse psychosocial outcomes in the 5-year period following amalgam placement.[28]Kingman et al.[29] studied correlation between exposure to amalgam and neurological functions. No significant associations between amalgam exposure and clinical neurological signs of abnormal tremor, coordination, gait, strength, sensation or muscle stretch reflexes or for any level of peripheral neuropathy in the subjects have been observed. A significant association was detected between amalgam exposure and the continuous vibro-tactile sensation response. The study reported that this association was a subclinical finding that was not associated with symptoms, clinically evident signs of neuropathy or any functional impairment.In the Children's Amalgam Trial, one of the secondary endpoints included renal functioning. The investigators assessed changes on markers of glomerular and tubular kidney function and urinary mercury levels. They found no significant differences between the treatment groups and no significant effects related to the number of dental amalgam restorations on the markers. Children in both treatment groups experienced micro albuminuria, but the prevalence was higher in amalgam group. The authors concluded that the increase in micro albuminuria may be random, but should be further evaluated.[30] The other safety trial was conducted in Lisbon, Portugal[27] in which a randomized controlled clinical trial carried out in 507 children 8- to 10-years old at baseline. They were evaluated for several years thereafter to determine if any health changes occurred following restorations with amalgam or composites. On carrying out annual standardized tests of memory, attention, physical coordination, and velocity of nerve conduction, the scientists did not detect a pattern of decline in the test scores of individual children who received amalgam restorations. They found a trend of higher treatment need in children receiving composite, thus suggesting that amalgam should remain a viable dental restorative option for children. The investigators performed annual clinical neurological examinations to assess neurobehavioral and neurological effects. The authors concluded that amalgam exposure had no adverse neurological outcomes.[31]The 7 years of longitudinal data provide extensive evidence about relative safety of amalgam in dental treatment. Substantial amalgam exposure did lead to creatinine adjusted urinary mercury levels that were higher in the amalgam group. Children with amalgam restorations had slightly elevated levels of mercury in their urine, measuring on average 1.5 μg/L of urine for the first two years and levelling off to 1.0 μg/L or less thereafter. However, these values fall within the background level of 0–4 μg/L, which is usual for an average person not exposed to industrial or other known sources of mercury.[32] Thus, the longitudinal studies on the use of amalgam in children did not suggest any negative effects on neuropsychological function or renal function within the 5-year follow-up period. It was reported that urinary mercury concentrations were highly correlated with both the number of amalgam restorations and the time since placement in children. The finding suggested that there may be sex-related differences in mercury excretion. They found that females have significant increase in the rate of mercury excreted in urine than males. Thus, this association might confer a lower mercury toxicity risks in females.[33] Dunn et al.[34] evaluated scalp, hair, and urine mercury content of children collected over the 5-year period, mean hair mercury level was 0.3–0.4 μg/g and mean urinary mercury level was 0.7–0.9 μg/g creatinine. The authors reported that use of chewing gum in the presence of amalgam restoration was a predictor of higher urinary mercury levels. Data suggested that amalgam-associated mercury exposure might be reduced by avoidance of gum-chewing in the presence of amalgam restorations.Sixty children were studied to assess urinary mercury excretion and its relation to amalgam restoration and fish consumption. Children with amalgam restorations had significantly higher urinary mercury levels compared to children with non-amalgam restorations. The urinary mercury levels in the amalgam group were well below levels that are known to cause adverse health effects.[35]Health effects related to mercury exposure in adultsAn investigation on 20,000 people in the New Zealand Defence Force between years 1977–1997 was done to find out association between amalgam restorations and disorders related with nervous system and kidney. No significant correlation between amalgam restorations and chronic fatigue syndrome or kidney disease was observed. A slightly elevated risk for multiple sclerosis was reported, but may have been due to confounding variables.[36] In another study, where few patients believed that their amalgam restoration made them ill, medical examination including physical examination, electrocardiogram, abdominal sonography, and blood chemistry was done. The study concluded that symptoms of the patients were due to psychological factors. There was no connection between the mercury levels in the patient's blood, urine, and saliva and their symptoms.[37] The association between amalgam and multiple sclerosis was assessed via a systematic review and meta-analysis. Three case control studies and one cohort study met their inclusion criteria. The meta-analysis revealed a slight nonstatistically significant increase between the presence of amalgam restorations and multiple sclerosis. The study does not provide evidence for or against an association.[38]Halbach et al.[39] evaluated the internal exposure to amalgam-related mercury and estimated the amalgam-related absorbed dose of mercury. The integrated mercury absorbed from amalgam restorations was estimated at up to 3 μg per day for an average number of restorations and 7.4 μg per day for a high amalgam load. The authors concluded that these estimates are below the tolerable dose of 30 μg per day established by WHO.Hypersensitivity reactions by amalgam restorationsAmalgam is capable of producing delayed hypersensitivity reactions in some individuals. These reactions usually present with dermatological or oral symptoms. The constant exposure to mercury in amalgam restorations may sensitize some individuals, making them more susceptible to oral lichenoid lesions. These oral lesions are rarely noticed by the affected individuals and cause no discomfort. There is evidence that a certain percentage of lichenoid lesions are caused by amalgam restorations,[40] but other restorative materials can also cause lichenoid lesions. It was also noted that the restorations associated with lichenoid lesions are poorly contoured, corroded and old. Hence corrosion of amalgam restoration or perhaps the biofilm present on such restorations may contribute to the development of hypersensitive reaction rather than material itself.[41] Symptoms of an amalgam allergy include skin rashes in the oral, head and neck area, itching, swollen lips, localized eczema-like lesions in the oral cavity. These clinical signs usually require no treatment and will disappear on their own within a few days of exposure. However, in some instances, an amalgam restoration will have to be removed and replaced with alternate restorative material. The replacements have led to significant improvements.[42] Although mercury allergy is rare but sometimes hypersensitivity to it may lead to dermatitis or type IV delayed hypersensitivity reactions most often affecting the skin as a rash.[43]Mercury exposure in dental professionalsDentists and dental nurses are at risk of potential exposure to inorganic mercury through their handling of amalgam, although now days their exposure has reduced due to low mercury to alloy ratio and through mercury management. One hundred and eighty dentists were evaluated in West Scotland for mercury exposure and its effects on their health and cognitive function. Dentists were found to have, on an average, over four times the level of urinary mercury compared to age and education-matched control subjects. The authors reported that based on their questionnaire, dentists were more likely to report having a disorder of the kidney, although the effect was not significantly associated with their urinary mercury level. An age effect was found for memory disturbances in dentists but not in the control subjects. There was no significant association between urinary mercury concentrations and self-reported memory disturbance.[44] A study on 43 dental nurses, with an average age of 52, were exposed to copper amalgam with a 30-year follow-up; were compared with 32 matched controls. It was concluded that the dental nurses did not appear to be neurobehavioraly compromised. Seven symptoms of mercury poisoning that were reported at a higher rate by exposed group than by the control group (arthritis, bloating, dry skin, headache, metallic taste, sleep disturbances, and unsteadiness). It did not appear that the investigators performed post-hoc testing to compensate for multiple comparisons.[45] The possible health risk of occupational exposure to mercury vapour in the dental office was assessed by evaluating the cytogenetic examination of leukocytes and blood mercury levels of dentists.[46] Genotoxicity of occupational exposure to mercury vapour in ten dentists was evaluated. The authors concluded that mercury vapour concentration in blood was below 0.1 mg/m3 and did not exhibit cytogenetic damage to leukocytes.Mercury management in dental operatoryIn 1999, the ADA Council on Scientific Affairs adopted mercury hygiene recommendations to provide guidance to dentists and their staff members for safe handling of mercury and minimizing the release of mercury into the dental office environment. These were updated in 2003 and are as follows: work in well-ventilated areas, remove professional clothing before leaving the workplace, periodically check the dental operatory atmosphere for mercury vapour, (use dosimeter badges or use of mercury vapour analysers for rapid assessment after any mercury spill or clean-up procedure). The current Occupational Safety and Health Administration (OSHA), standard for mercury is 0.1 mg per cubic meter of air averaged over 8-h work shift. The National Institute for Occupational Safety and Health has recommended the permissible exposure limit to be changed to 0.05 mg/m3 averaged over 8-h work shift over a 40-h workweek.[47] During preparation and placement of amalgam only precapsulated amalgam alloys should be used. If possible, recap single-use capsules after use, store them in a closed container and recycle them. Avoid skin contact with mercury or freshly mixed amalgam. Use high-volume evacuation systems when finishing or removing amalgam. Floor coverings should be non absorbent, seamless and easy to clean. Use of carpet in operatory is not recommended where an accidental mercury spill might occur. Chemical decontamination of carpeting may not be effective, as mercury droplets can seep through the carpet and remain inaccessible to the decontaminant. In case of accidental mercury spill a vacuum cleaner should never be used to clean up the mercury. Small spills (less than 10 g of mercury present) can be cleaned safely using commercially available mercury cleanup kits.Amalgam substitutesIn the recent year's composites, glass ionomer cements and a variety of hybrid structures have been used due to increased demand for aesthetic restorations. Composite serves better than amalgam when conservative preparation is recommended like small occlusal restorations, in which amalgam require removal of more sound tooth structure.[48] Composites have different setting reaction mechanisms and it interacts with the patient's tissues in different ways . The small organic molecules (monomers) react to form polymers. Some of the monomers may not have reacted during placement and therefore low levels remain in the set restoration, which are known to be toxic to cells and others may cause allergic reactions. The effects they cause vary depending on the substance and on the type of body tissue with which they come into contact. Concerns have been raised about the endocrine disrupting (in particular, oestrogen-mimicking) effects of plastic chemicals such as “Bisphenol A” used in composite resins.[49]Amalgam possesses greater longevity than composite.[50] However, this difference has decreased with continued development of composite resins.[51] Amalgam is moderately tolerant to the presence of moisture during placement. In contrast, technique for composite resin placement is more sensitive and require “extreme care” and “considerably greater number of steps”.[51] Mercury acts as bacteriostatic agent whereas TEGMA (constituting some older resin-based composites) “encourages the growth of microorganisms”.[51] The New England Children's Amalgam Trial suggested that the longevity of amalgam is higher than that of resin-based compomer placed in primary teeth and composites in permanent teeth.[50,52] Compomers and composites were seven times likely to require replacement than amalgam.[52] “Recurrent marginal decay” is the main reason for failure in both, amalgam and composite restorations, accounting for 66% (32/48) and 88% (113/129), respectively.[53] “Christensen[50] quoted Amalgam restorations are and will continue to be the mainstay of posterior tooth restorations for many years to come.” Though use of amalgam has decreased during the past few years, more studies on safety of composites or other aesthetic materials with long-term follow-up of are necessary before they can be considered a definitive alternative for amalgam.CONCLUSIONThe current use of amalgam has not posed a health risk apart from allergic reactions in few patients. Clinical justifications have not been available for removing clinically satisfactory amalgam restorations, except in patients allergic to amalgam constituents. Mercury hypersensitivity is an immune response to very low levels of mercury. There is no evidence that mercury released from amalgams results in adverse health effects in the general population. If the recommended mercury hygiene procedures are followed, the risks of adverse health effects in the dental office could be minimized. Amalgam is safe and effective restorative material and its replacement by nonamalgam restorations is not indicated. Also a recent review by the American Dental Association Council on Scientific Affairs states that: “Studies continue to support the position that dental amalgam is a safe restorative option for both children and adults. When responding to safety concerns it is important to make the distinction between known and hypothetical risks.”