Was “Good Science” Really Applied in the Recent Mercury Report Issued by the Florida Department of Environmental Protection?

Guest essay Dr. Willie Soon

(Note: the newspaper The Florida Times-Union at jacksonville.com refuses to allow Dr. Soon to post a rebuttal fitting the word length and other editorial restrictions, so he has offered this expanded essay. He asks readers to distribute this widely.  – Anthony)

As a scientist who has spent the past ten years studying the science of mercury (Hg) and the biologically toxic form of mercury, methylmercury (MeHg), I was taken aback by the clear misuse of the phrase “good science” in a recent letter by Florida DEP’s director of the Division of Environmental Assessment and Restoration (published in the Florida Times-Union newspaper).

The director referred to FDEP’s draft report[1] in setting a strict mercury limit in Florida’s river, stream, lake, and coastal waters, which was released May 24. After a careful examination of the draft report, however, I have come to the conclusion that it contains serious flaws such that the strict mercury limit proposed by FDEP is not scientifically defensible.

First, FDEP’s notion that mercury “pollution” in our air, water, and land is a new, manmade phenomenon is simply wrong. While FDEP cited a 2008 paper[2] that reported mean mercury levels of 0.25 parts per million (or ppm) in the hair of a group of women of childbearing age (16 to 49) in the Florida Panhandle, a study of 550-year-old Alaskan mummies[3] reported average hair mercury levels of 1.2 ppm for four adults and 1.44 ppm for four infants. One mummy had hair mercury levels as high as 4.6 ppm!

Even more importantly, the FDEP draft report failed to consider the 17-year-long Seychelles Islands study,[4] which found no harm, nor any indications of harm, from mercury in children whose mothers ate 5 to 12 servings of fish per week. In establishing the exposure risk of MeHg by fish consumption (most relevant to Floridians), the authors of this study argued that no consistent patterns of adverse associations existed between prenatal MeHg exposures and detailed neurological and behavioral testing. They concluded that despite the risk of MeHg to expectant mothers, “ocean fish consumption during pregnancy is important for the health and development of children and that the benefits are long lasting.” Indeed, the latest Centers for Disease Control data show blood mercury levels for U.S. women and children are already below EPA’s “safe” levels for mercury—the most restrictive mercury health in the world.

It is useful to note the FDEP draft report cited a 1972 study that confirmed tuna mercury levels in the past were higher (or at least not substantially lower) than tuna caught in the world’s oceans today. Although expecting to find a 9 percent to 26 percent increase in levels of MeHg, Princeton University scientists found no increase (actually, a minor decline) in fish tissue mercury levels after comparing Pacific Ocean tuna samples from 1971 and 1998. Those scientists concluded fish mercury level “is not responding to anthropogenic emissions irrespective of the mechanisms by which mercury is methylated in the oceans and accumulated in tuna.”[5]

Second, it is curious that the FDEP draft report failed to note that forest fires in the state of Florida alone were estimated to emit more than 4,000 lbs of mercury per year from 2002 to 2006 alone.[6] This single source of local mercury emissions is comparable to, if not significantly higher than, the mercury emitted for 2009 from all manmade mercury sources in Florida, including coal-fired power plants (which emit less than 1,500 lbs per year).

The FDEP draft report also repeatedly mentioned volcanoes as an important source of global mercury emissions but somehow fell short in conveying the full scale of this natural source of mercury. A new study[7] in the January 2012 issue of the journal Geology noted a truly huge emission of mercury during the Latest Permian era (about 250 million years ago) where the event was estimated to emit about 7,600 tons per year! This is about four times larger than current estimates of the amount of manmade Hg emissions globally, and it persisted for nearly 500,000 years.

Such large sources of mercury resulting from the natural environment can explain why it is not surprising to find high levels of mercury in old samples taken before contamination by modern sources of mercury emission. These high levels have been observed in the hair of Florida panthers and south Florida raccoons as well as fish and aquatic life.

It is equally important to dispel the false impression from the FDEP draft report that mercury “pollution” in Florida’s watersheds and fishes is increasing. A note of caution from the U.S. EPA is clear: Contaminants in fish have been increasingly monitored since the 1970s, which has resulted in more advisories being issued due solely to increased sampling by the various states and “not necessarily due to increased levels or frequency of contamination.”

I would further note there is a serious flaw in FDEP’s draft report that sets a mercury limit of 1.25 parts per trillion (or 0.00000125 ppm) as the new standard for Florida’s inland and coastal waters. It is tacitly assumed by the FDEP that water mercury levels are directly related to fish tissue mercury levels. In fact, no such relationship exists, and indeed the FDEP draft report admits on page 58 that “Using the data collected for the [Florida Mercury Project], no relationship is observed when comparing total mercury in the water column to total mercury in fish tissues.”

Perhaps it is time for FDEP to reconsider the scientific basis of its mercury rulemaking.

Why is the FDEP so intent on setting mercury levels below those existing in nature? Why is it so difficult for the FDEP to fully disclose or explain such publicly available information from the scientific literature to all concerned citizens of Florida? Scientific inquiry must be above political pressure and partisan advocacy. Good decisions can arise only if the scientific evidence and knowledge are examined fully, without a selective bias.

###

Willie Soon is an independently minded Ph.D. scientist who has been studying the biogeochemical nature of mercury in our environment and ecosystem for the past 10 years.

The above article is in response to this letter from Florida DEP:

http://jacksonville.com/opinion/letters-readers/2012-05-26/story/lead-letter-state-will-use-good-science-environment

Opinion / Letters From Readers
Lead letter: State will use good science for environment
Posted: May 26, 2012 – 12:09am  |  Updated: May 26, 2012 – 1:23am
The future

of Florida’s environment and economy depend on the health of our waterways. That’s why one of the top priorities of the Florida Department of Environmental Protection is getting Florida’s water right in terms of quality and quantity.
As part of our efforts, DEP is taking additional action to protect Florida’s water by improving our water quality standards and setting restoration goals.
Florida has always been a national leader in assessing and addressing the health of our waterways. Our efforts to advance environmental science account for 30 percent of the national water quality dataset, more than any other state in the nation.
We use this science to set standards, or thresholds, for the amount of nutrients or contaminants that can exist in a healthy body of water. These water quality standards are important to protecting public health and the aquatic life in Florida’s water bodies.
Many readers may remember DEP’s efforts last year to set rules for the amount of nutrients in Florida’s water bodies. We’re committed to implementing our rules and will continue the effort this year by establishing criteria for Panhandle estuaries from Perdido to Apalachicola Bay.
DEP is also launching an effort to adopt new, Florida-specific water quality standards to protect our citizens from eating contaminated fish and to protect our fish from harmful low dissolved oxygen conditions.
Florida’s current standards are based on science created more than 30 years ago. We intend to move forward with these new standards by using updated, Florida-specific research.
For example, because Floridians consume more seafood than the average U.S. resident, we need to develop a more protective water quality standard for fish consumption than states where residents eat less seafood.
Along these same lines, DEP is taking action to establish a mercury reduction goal (known as a Total Maximum Daily Load or TMDL) to address levels of mercury found in some Florida fish.
When adopted, this will be the nation’s first mercury TMDL that addresses both freshwater and marine fish on a statewide basis.
DEP is also working to update criteria related to the amount of oxygen needed in waterways to protect fish and other wildlife. Our science has been peer-reviewed and is the basis of our rule development process.
There will be another opportunity for public participation during the second round of workshops, which we plan to hold in July.
I encourage Floridians to learn more about DEP’s rules and efforts to protect water quality by visiting www.dep.state.fl.us. We can all play a role in getting Florida’s water right.
Drew Bartlett, director, Division of Environmental Assessment and Restoration,
Florida Department of Evironmental Protection


References:

[1] http://www.dep.state.fl.us/water/tmdl/docs/tmdls/mercury/florida-merc-tmdl-draft-052412.pdf.

[2] Karouna-Renier et al. (2008) Environmental Research, vol. 108, 320-326.

[3] See Middaugh on pp 53-68 of July 24, 2002’s FDA’s Food Advisory Committee on MeHg.
(http://www.fda.gov/OHRMS/DOCKETS/ac/02/transcripts/3872t2.htm) and also Arnold and Middaugh (2004) in Use of Traditional Foods in a Healthy Diet in Alaska: Risks in Perspective (available at: http://www.epi.hss.state.ak.us/bulletins/catlist.jsp?cattype=Mercury).

[4] Davidson et al. (2011) Neurotoxicology, vol. 32, 711-717. Note that the evaluations and tests have also been done for the main cohort of SCDS at age 19 years.

[5] Kraepiel et al. (2004) Environmental Science & Technology, vol. 38, 4048 and see also Kraepiel et al., (2003) Environmental Science & Technology, vol. 37, 5551-5558.

[6] Wiedinmyer and Friedli (2007) Environmental Science & Technology, vol. 41, 8092-8098.

[7] Sanei et al. (2012) Geology, vol. 40, 63-66.

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John West
June 4, 2012 11:59 am

“Our science has been peer-reviewed and is the basis of our rule development process.”
There’s the “tell”, it’s a gnostic religion. They apparently possess certain science (secret knowledge) which supports certain policy decisions. There’s no reason to look at any other(‘s) science, they have the science they need.

Kelvin Vaughan
June 4, 2012 12:02 pm

I swallowed some mercury once by accident. The only problem I noticed was when the temperature gets above 30°C I get an erection.

Latitude
June 4, 2012 12:08 pm

based on science created more than 30 years ago…..
…………Our science has been peer-reviewed and is the basis of our rule development process.
What a bunch of uppity…………….

just some guy
June 4, 2012 12:09 pm

dtcg?

Don
June 4, 2012 12:34 pm

Sorry to tell you, Kelvin, but yours will be a death by degrees. ;->

Alcheson
June 4, 2012 12:37 pm

These new ultra-low levels of Hg rules are being put into place to shut down fossil fuels as a source of energy and for no other reason…. plain and simple. Mercury rules in place in the 1990s are more than adequate for providing a safe environment for all Americans.

Bob W in NC
June 4, 2012 1:14 pm

“Alcheson says:
June 4, 2012 at 12:37 pm
These new ultra-low levels of Hg rules are being put into place to shut down fossil fuels as a source of energy and for no other reason…. plain and simple…”
And so—what is the EPA doing about getting rid of the tsunami of mercury that is coming when CFLs are not recycled properly? Oh, wait… CFLs are green, aren’t they? [sarc]

paddylol
June 4, 2012 1:16 pm

When the term “peer review” is used by a government agency, it refers to review by peers, co-workers, who work for the same agency.

Stephen Richards
June 4, 2012 1:47 pm

Kelvin Vaughan says:
June 4, 2012 at 12:02 pm
“I swallowed some mercury once by accident. The only problem I noticed was when the temperature gets above 30°C I get an erection.”
I must try that. The only problem I can foresee is that over 30°C it’s too hot for me to need one. :))

John West
June 4, 2012 1:57 pm

They’ll need to do something about forest fires as well:
http://www.nsf.gov/news/news_summ.jsp?cntn_id=110320
Mercury is and always has been part of the biosphere that’s how it got into the coal in the first place.
See figure 2-2 for “pre-industrial” Hg Cycle swags, note: “Data collected over 25 years from many locations in the United Kingdom on liver mercury concentrations in two raptor species and a fish-eating grey heron indicate that peak concentrations occurred prior to 1970.”. http://www.epa.gov/ttn/atw/112nmerc/volume3.pdf

Gail Combs
June 4, 2012 2:15 pm

I have nothing but contempt for todays news media.
It would seem “freedom of speech” is alive and well in Florida… Well maybe.
Gannet Newspaper fires Journalists who may have uncovered evidence of
drug ring at apartment of accused murderer: http://www.casaplumeria.com/rapsheet/story1.htm
According to the Knight Center for Journalism in the Americas, blogger Chaz Stevens was issued a “cease-and-desist” legal notice from the Florida city of Lauderdale Lakes in February for his critical coverage of the city’s government.
Here’s why you can’t buy the News Journal at Wal-Mart… Wal-Mart didn’t appreciate a column Mark O’Brien…
Florida Reporters Win Trial Over Fox TV and Monsanto Suppressionof rBGH Story… Florida Reporters Awarded $500,000 in Damages after FOX TV Caved into
Monsanto and Killed an Investigative Series on the controversial
recombinant Bovine Growth Hormone

TV investigative reporters Jane Akre and Steve Wilson, who were fired after refusing to go along with misleading alterations to their story about Monsanto’s genetically-engineered bovine growth hormone.
Akre and Wilson recently won a landmark whistleblower lawsuit against the station that fired them, yet their former network continues its legal efforts to reverse the ruling and crush them financially…. http://www.purefood.org/rbgh/akrepart1.cfm

A popular anchor in Southwest Florida speaking out tonight after he says he was fired from WBBH NBC-2 News. Many viewers have wondered what happened to Craig Wolf, who anchored the news for 18 years…. Wolf claims he was fired for exposing ‘hazardous’ conditions at station
Journalists fired for taking gov’t money ~ Ten South Florida journalists, including three with The Miami Herald’s Spanish-language sister paper, received thousands of dollars from the federal government for their work on radio and TV programming aimed at undermining
A third journalist has lost a job in further fallout from NBC stations’ misleading editing of the call George Zimmerman placed to 911, just before he allegedly shot and killed unarmed Florida teen Trayvon Martin, according to TVNewser. An NBC spokesperson confirmed that Miami-based correspondent Lilia Luciano is no longer with NBC News…
Too bad Climate Scientists are not fired as readily as journalists are.

Lark
June 4, 2012 2:16 pm

See, that’s the problem with global warming – as Kelvin can tell you, it’s hard to be a good peer when the temperature gets above 30°C.
Or should that be “peeer”?

June 4, 2012 3:29 pm

The Great Salt Lake has very high concentrations of MeHg, about 90ppb. This has been linked by many to Utah’s high and growing rate of autism, and has been blamed on gold and copper mining as well as on coal burning. Most likely this Hg is ancient, having accumulated for millennia. As for the growing autism, it seems to be due to more inclusive definitions: autism has become a euphemism for retardation on the one hand, and more mild cases have been diagnosed by a growing profession on the other hand. Although the medical consensus on the use of thimerosol in innoculation is that it is harmless, the hysteria surrounding it has greatly limited its use anyway–bad environmental science typically wins.
Some years back a student brought some mercury to a local middle school, which was evacuated. Pseudoscience turned a thousand young teenagers onto the streets. Later on a federal building in Salt Lake was likewise evacuated due to some Hg spillage. Of course the schools continue to use and break mercury vapor lights indoors. It’s like evacuating a swimming pool in a thunderstorm–although nobody has ever been killed by lightening in a pool–the swimmers almost certainly are removed to more dangerous surroundings. Ignorance rarely loses. –AGF

June 4, 2012 4:03 pm

It would appear that good science it only that with which your bias agrees with. These people wouldn’t know good science if it bit then in ass.

Rob G.
June 4, 2012 4:47 pm

There are many other studies that suggest methylmercury’s association with epilepsy, developmental delay, lower scores in standardized tests, etc. It maybe (someone has to verify this) true that the other nutrients in that particular fish has done more good than bad for the islanders (in Ref 4), but that only suggests that intake of methylmercury in that fish may not be harmful, not that methylmercury is harmless (the authors in that article do not say methylmercury is not bad, in spite of their observation that tests scores went up with higher mercury levels, they only said eating fish is good) – mercury intake in other forms are not shown to be harmless. On the other hand, studies in Amazon (with fish eating population), Poland and other places shows adverse effects of mercury.
The overall mercury emission from forest fires in the U.S. is 44 tons per year, while the industrial emission is 108 tons per year. ( http://www.nsf.gov/news/news_summ.jsp?cntn_id=110320 ), so I see no problem with reducing industrial mercury emission. If forest fires are emitting that much mercury, then we should do even more to prevent forest fires, not increase industrial emission.
Alaskan mummies may have high mercuric content, but how do we know whether they had any health issues or cognitive issues?
Here are a few references that find adverse effects of methylmercury.
Methylmercury: A potential environmental risk factor contributing to epileptogenesis, Yuan, Yukun, NEUROTOXICOLOGY Volume: 33 Issue: 1 Pages: 119-126 DOI: 10.1016/j.neuro.2011.12.014 Published: JAN 2012
Effects of prenatal exposure to mercury on cognitive and psychomotor function in one-year-old infants: Epidemiologic cohort study in Poland, Jedrychowski W; Jankowski J; Flak E; et al. ANNALS OF EPIDEMIOLOGY Volume: 16 Issue: 6 Pages: 439-447 DOI: 10.1016/j.annepidem.2005.06.059 Published: JUN 2006
Qualitative assessment of visuospatial errors in mercury-exposed Amazonian children: Chevrier, C (Chevrier, Cecile)1; Sullivan, K (Sullivan, Kimberly); White, RF (White, Roberta F.); Comtois, C (Comtois, Callie)2; Cordier, S (Cordier, Sylvaine)1; Grandjean, P (Grandjean, Philippe) Source: NEUROTOXICOLOGY Volume: 30 Issue: 1 Pages: 37-46 DOI: 10.1016/j.neuro.2008.09.012 Published: JAN 2009
Neurocognitive screening of mercury-exposed children of Andean gold miners: Counter, SA (Counter, S. Allen); Buchanan, LH (Buchanan, Leo H.); Ortega, F (Ortega, Fernando) Source: INTERNATIONAL JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HEALTH Volume: 12 Issue: 3 Pages: 209-214 Published: JUL-SEP 2006

Ian W
June 4, 2012 5:11 pm

I think that Governor Rick Scott needs to look into this rather than just into insurance scams. This would appear to be the thin end of a wedge that is intended to be used against industry. As someone who lives in Florida I find it unacceptable that the Florida Department of Environmental Protection should demonstrate such ignorance of the natural world and a lack of professionalism in their work.

Brian R
June 4, 2012 6:37 pm

Here’s the game they play. By setting the acceptable level of MeHg below natural levels, they will be able to accuse and thus fine whom ever they want to no end.
It’s like the sound level fines DIA(Denver International Airport). Nobody noticed how low the levels were set until Sept 11-12, 2001 when the no-fly thing happened. DIA was fined for excessive noise levels during a time that no planes flew. The background noise levels were above the cut-off.

June 4, 2012 7:45 pm

Kelvin’s sex life will be less interesting when global cooling sets in. 😉

Grey Lensman
June 4, 2012 7:52 pm

For all, there are two good papers on this subject, here on WUWT
http://wattsupwiththat.com/2012/04/01/me…kster-god/
http://wattsupwiththat.com/2012/03/31/th…l-madness/
Enjoy

June 4, 2012 8:24 pm

To add to what Grey Lensman said, these two articles were some of my favorites here on WUWT. The fact that natural emissions of mercury from the ocean can be tracked to causing increased mercury in the natural world is case in point that this is just a trumped up idioacy to push a certain agenda.
And never mind the fact that we have lightbulbs which according to this criteria are quite more hazardous when broken. These lightbulbs are pushed on us by a Government that does it for the environment…quite ironic when you hear about mercury “pollution.”
Green must mean that some forms of mercury are more equal then others.

kadaka (KD Knoebel)
June 4, 2012 9:35 pm

From benfrommo on June 4, 2012 at 8:24 pm:

To add to what Grey Lensman said, these two articles were some of my favorites here on WUWT. (…)

Which is quite interesting as Grey Lensman messed up the URL’s. Here are the correct ones:
http://wattsupwiththat.com/2012/04/01/mercury-the-trickster-god/
http://wattsupwiththat.com/2012/03/31/the-epas-mercurial-madness/
Both Willis Eschenbach posts BTW.

kadaka (KD Knoebel)
June 4, 2012 9:57 pm

Re Kelvin Vaughan comment:
Well the above reply letter did mention mercury in wood….

Grey Lensman
June 4, 2012 10:08 pm

Rob G said
Quote
Alaskan mummies may have high mercuric content, but how do we know whether they had any health issues or cognitive issues?
Unquote
Misses the point and misdirects. The question is where did the mercury come from?
Re mis-links, just copied and pasted from my little blog where the subject was being discussed before this oost was made. So I was able to add this as a third link. Thanks for the correction.

June 4, 2012 10:17 pm

Unfortunately, peer review does not guarantee good science.
California (where I live and work) has a regulatory peer review requirement, but still has many examples of regulations based on bad science.

Kelvin Vaughan
June 5, 2012 1:56 am

Kelvin Vaughan says:
June 4, 2012 at 12:02 pm
I swallowed some mercury once by accident. The only problem I noticed was when the temperature gets above 30°C I get an erection.
Just a warning to any one thinking of doing this, Alcohol has the opposite effect!

John Marshall
June 5, 2012 2:47 am

In the UK there was a small family run business repairing and making mercury barometers. It was closed down bu the EU because it used 100Kg of mercury a year and an accident would damage the environment despite no accidental spillage ever happening. That same year the EU legislated the use of cfb light bulbs that all include mercury and get dropped, thrown in land fill etc..

mfo
June 5, 2012 6:03 am

The letter from Dr Willie Soon with its reasonable, factual and measured content stands in marked contrast to the vague and bureaucratic tone of the letter from the Florida Department of Environmental Protection. It’s fortunate that WUWT is a forum where information from an expert, showing another side of an issue, can be published to make up for the failings of the press.
Dr Soon I’m sure knows much more than I do about the following aspect of mercury, so apologies in advance if I’m wrong in any way. But I believe dental amalgam containing about 50% mercury (HG) is the main source of mercury potentially affecting humans as vapour or through careless disposal. Though the Center for Disease Control and Prevention, and the Food and Drug Administration both consider the level of mercury in dental amalgam fillings to be safe.
A quick look at the EPA’s website shows that mercury in consumer products dropped by 83% between 1980 and 1990. In 2004, 30.4 tons of mercury (26% of mercury in all products) was sold in dental amalgam. This is apparently declining because of better dental health and alternative filling materials.
The main concern seems to be the careless disposal of mercury amalgam by dentists. The EPA has estimated that in 2008 there were approximately 122,000 dental offices (approximately 160,000 dentists) that used or removed dental amalgam in the U.S., and that those offices discharged approximately 3.7 tons of mercury each year to Publicly-Owned Treatment Works (POTWs).
Dental offices were found in 2003 to have been the source of 50 percent of all mercury pollution entering POTWs. However the EPA confirm that POTWs have around a 90% efficiency rate of removing amalgam from wastewaters. Only a small amount of waste amalgam is discharged from POTWs into surface water to become methylmercury.
In a study in 2002, Mercury Source Control & Pollution Prevention Program Evaluation, the National Association of Clean Water Agencies (NACWA) estimated that nearly 40 percent of the mercury in the nation’s wastewater system came from dental offices, and that mercury discharged from dental offices far exceeded all other commercial and residential sources, each of which was below ten percent.
It strikes me that simply by using fillings without mercury and the safe disposal of existing fillings when removed would make a significant difference to mercury from human sources reaching the environment in the US and without imposing a stricter mercury limit in Florida’s river, stream, lake, and coastal waters.

Rob G.
June 5, 2012 6:15 am

Roger Sowell says: June 4, 2012 at 10:17 pm “Unfortunately, peer review does not guarantee good science.”
Not always, but close scrutiny even after the publication generally will. Unfortunately there are no better process than peer review (with different variants) to set some standard and accuracy by people who knows the subject well. The article by Willie Soon is not even peer reviewed, it is just an opinion; so it does not even have the minimum protection from a peer review. In fact I cannot find a peer reviewed article by Willie Soon on mercury.

Rob G.
June 5, 2012 6:48 am

Grey Lensman says: “Misses the point and misdirects. The question is where did the mercury come from?”
Sure, Grey, I understood the point – the sources of mercury were all natural and it was probably high at that time. But Alaskan people didn’t have a choice, they did not know enough about mercury or its effects, they did not emit mercury (other than probably burning wood for cooking, etc), so they had no choice. Our state is far different that theirs- the natural emission seems to be much smaller than 500 years ago (otherwise combined with human emission, the women tested recently will have more mercury in their hair) and If indeed methyl mercury is bad, then we can do something about it, unlike 500 years ago.
There are cases from history that forces us to be cautious: CFCs, asbestos, etc. Take for example asbestos – naturally occurring, used for 4000 years but became popular in late 1800s. Suspicion of toxicity was identified as early as 1907, widespread recognition of health problems by 1930s, but there were people defending its usage and safety during this time. Increased restrictions on asbestos only came recently, and even with all we know now, people like Steven Milloy appear to continue to support its use. (He also does not find any issues with small particles from coal burning, that is now covering China – essentially wanting to bring that smog to the U.S. with increased coal use). This is why I have a credibility problem with many of them.

Dagfinn
June 5, 2012 9:06 am

Since dental amalgam has come up, I get the urge to repeat some of the lesser known facts about it. It’s ironic that mercury exposure from environmental sources has become exclusively focused in contrast to the direct exposure from amalgam fillings, which is (or at least was 10-20 years ago) the main source of exposure for most people. It’s also almost certain to cause health problems or neurological impairment in at least some people, since a minority of amalgam bearers (especially avid gum chewers and those who grind their teeth at night) have been shown to be exposed at or above traditional occupational exposure limits.
When Dr. Soon states that methyl mercury is the “biologically toxic form of mercury”, I assume he is aware that this is at best an oversimplification. All forms of mercury are toxic to some extent as far as I’m aware, although some forms are hardly absorbed. And mercury vapor is similarly toxic to methyl mercury, since both readily cross the blood-brain barrier and the placenta. (Inorganic mercury salts are considered much less toxic since they don’t).
Mercury vapor is released from dental amalgam fillings which are approximately 50 per cent mercury. The fillings accumulate corrosion products that protect the surface from releasing mercury, but these corrosion products are stripped away when chewing and the mercury is inhaled and absorbed into the blood stream. The corrosion products are swallowed, but are not absorbed to any significant degree, and are harmless compared to the mercury vapor. However, this mercury (via human feces) contributes to mercury pollution in sewers.

Richard George
June 6, 2012 12:11 am

The first rule of environmental regulators is never let science get in the way of a political agenda. The Florida DEP is a political division of the State not a science organization. They violate the most basic rule of toxicology by assuming sub-chronic doses of natural occurring metals are harmful. Somehow all the levels below an observable affect magically add up to a level that has one. If they are willing to ignore the most basic rule, what make anyone believe they are interested in the more subtle ones?

Galane
June 6, 2012 2:30 am

“Why is the FDEP so intent on setting mercury levels below those existing in nature?” Because they’re people of the same school that insists on using rubbish terms like “vacuum pressure” and evacuating entire schools, bringing in hazmat cleanup and removing all the carpet from a science classroom over a single broken thermometer when a Rug Dr. would work just fine.
Want even more such crazy? Google columbia river parts per quadrillion. Some environuts apparently expect that river to be pure distilled water – or at least pure enough to kill every living thing in it. (Yes, pure enough to kill. Water with nothing but water in it is not healthy to drink. It will absorb salt and other vital stuff from your body. Distill *and* deionize it and it’s even worse.)
Mercury, dioxins and many other “contaminants” are naturally found in the environment. I’ve gone gold panning and found enough free mercury under rocks to do (according to these nuts) huge environmental damage.
How did the mercury get there? Leaching from cinnabar ore, naturally. That was the easiest method of finding good sites to mine for mercury, look under rocks in streams.

COB
June 6, 2012 5:39 am

Some years ago there was a study of mercury levels in various 100+ yr old Billfish trophy mounts that indicated that mercury levels in the seas top predators have been high for a long time.
Then there is this
This strikes me as much to do about nothing.

COB
June 6, 2012 5:41 am

And the Link went where? We’ll try again.
http://www.sciencedaily.com/releases/2008/06/080629081932.htm

The iceman cometh
June 6, 2012 6:29 am

One of the problems with setting limits on supposed pollutants is that bureaucrats who set the limits keep wanting tighter limits – it gives them ‘work’. This example, of a bureaucrat wanting mercury levels lower than natural, is just one of a long list that illustrates the problem. Acid rain was another great one (anyone remember that?). I keep up a tease of the NY Department of the Environment, which assures me that in some parts of the Adirondacks the lake waters are so acid they are toxic to fish. I refer them to the Adirondack Tourism Council, which steadfastly says there is no such problem – the fishing is great everywhere there is a lake. Where the problem gets really serious is radiation. The natural background in many parts of the world is over 10 times the allowable dose for radiation workers, which is ten times the allowable dose for the general population. Yet those who live in the high natural background regions show no effects as a result of the radiation. There is growing evidence for hormesis – a little radiation improves your life expectancy. Yet the target of zero anthropogenic dose remains widespread. Nearly all nuclear plants would be closed if they emitted as much radon as the average coal-fired power station. What is the answer? I think we have to challenge every move to tighten limits wherever the scientific evidence of demonstrable harm is lacking.

Jeff Alberts
June 6, 2012 7:40 pm

It’s like evacuating a swimming pool in a thunderstorm–although nobody has ever been killed by lightening in a pool–the swimmers almost certainly are removed to more dangerous surroundings.

Quite a bit of lightening goes on in pools, due to chlorine. But I don’t recall ever hearing of any deaths as a result.
Oh, you mean lightning.