By Teresa Conrick
Megan, my daughter born in 1993, came into the world with beautiful BLUE eyes. In the picture here, right before her 5th birthday, you can see just how blue they were. Megan had been diagnosed with autism in 1995 and LOSING EYE CONTACT was the first step into the darkness of this disease/disorder back then. That may have been a clue.
As the years have gone by, Megan's eye color has changed into a brownish green, as shown in the other photo, taken last year. It was not an abrupt change but more gradual. In my last post about mercury and the eye issues of autism HERE, I focused on the vision/ocular issues of autism, like strabismus and visual field constriction, that mercury could cause. Now I want to take a look at the research that might help illustrate what may have happened to cause my daughter's eye color to change.
I had these two photos on Facebook and many people commented and shared that their child with an autism diagnosis also has vision and ocular issues. I wanted to post them here with more detail to get a better sense of the extent of mercury and issues with the eye - including autism. The "symptom" of eye color change is maybe another key, a possible visual, so to speak, into the canaries of the epidemic. The eye issues of autism do seem to correlate with known damage to the eye by mercury:
"MERCURIALENTIS WAS FIRST BROUGHT TO OUR ATTENTION BY DR WALTER ATKINSON in 1942. At the annual meeting of this Society, he reported the slit lamp observation of a "brownish colored reflex" on the anterior capsule of the lens in 36 of 70 persons who were working with mercury in the manufacture of thermometers.....In addition to thermometer workers, it has been found amongst direct-current meter repairers, in the felt hat industry, and in workers exposed to the mercury-zinc amalgams of batteries......We wish to report the deposition of a pigment on the anterior capsule of the lens in 31 patients who had used a number of topical medications, each containing a mercurial preservative....Since 1965, 31 patients have been noted to have pigmentation of varying color and intensity in the pupillary portion of the anterior capsule of the lens....The pigmentation of the lens was observed as early as three years after the commencement of the topical medication in two patients, and as late as 15 years in another......"
"......We have estimated that more than 500 patients under our care have used mercury-containing eye drops two to four times a day for periods of more than six years. Of these, only 31 patients were found to have lens pigmentation and only two of these had corneal deposits. This represents roughly, a 6% incidence of observed pigmentation. Why there is so much variation as to the time of appearance of pigmentation in patients and why the deposition occurs in some patients and apparently not at all in others, is difficult to explain."
Risk management for hazardous chemicals, Volume 7 "Mercury accumulates in the body with each exposure ....... Repeated exposure from inhalation, absorption, or both can cause central nervous system effects"... and in that lengthy list of effects ....... "visual disturbances and changes in eye lens color" ..... "Repeated exposures may also cause reduced peripheral vision and brown staining of the eye."
"Mercury - chronic exposure:
Eyes - grey or brown lens discolouration, band shaped corneal
opacities......."Chronic exposure usually occurs from inorganic mercury salt ingestion, inhalation of industrial or agricultural vapours or exposure to mercurial fungicides in paint. Mercury vapour exposure to the eyes can cause conjunctivitis and eyelid tremor.... "Chronic exposure may lead to grey or brown lens discolouration or band keratopathy."
Effects of mercury intoxication on the response of horizontal cells of the retina of thraira fish (Hoplias malabaricus)
"The visual system is an important target of mercury intoxication. Investigation of the neuro-ophthalmological aspects of the mercury intoxication that caused Minamata disease started with the measurement of the visual field performed by Iwata and Abe......The effects of mercury intoxication on the retinae of vertebrates are still little known. In studies on the squirrel monkey, mercury vapor inhaled by the mother accumulated in several tissues of the neonate's retina - the optic nerve, the inner plexiform layer and the ganglion cells, - and was also concentrated in the pigment epithelium and in blood vessel walls. It has also been observed that mercury accumulates in the rod photoreceptor cells of the monkey retina."
Uveal Melanocytes, Ocular Pigment Epithelium, and Müller Cells in Culture: In Vitro Toxicology
"Uveal melanocytes and the ocular pigment epithelium are located in the middle and inner layers of the eye. Müller cells (a type of glial cell) are located in the neural retina. Melanocytes, retinal pigment epithelium (RPE), and Müller cells do not participate directly in the detection or transfer of visual information, but they have various functions that support the neural retina and are essential for the maintenance of vision.....Toxic effects on these cells may give rise to altered retinal function and result in impaired vision. Both melanocytes and pigment epithelium contain melanin, which has the ability to bind organic amines and metal ions. This results in the accumulation of these substances in the eye. Melanin may protect cells from chemical stress by binding toxic chemicals; but in chronic exposure, increased and lengthy binding may cause damage to these cells."
Another team of researchers who recently tackled the issue of both methyl and ethyl mercury compounds (thimerosal) and their effects on the eye, discovered new and disturbing information. Their study HERE, which I also discussed in my last post on autism and vision issues, started with this:
"Strikingly, the greatest accumulation of methyl and ethyl mercury compounds was highly localized in the rapidly dividing lens epithelium," and showed that both types of mercury could cause damage to the eye - "We observe highly preferential accumulation of Hg in the outer layer of the eye lens...a level more than four times higher than in other tissues examined .... the highest Hg at the periphery of the eye lens, were observed in tissues from larvae treated with another organomercury (C–Hg) thimerosal."
They then compare the zebrafish lens of the eye to the rings of a tree, where you can ascertain information over the years - and that information may reveal quite a bit:
"Thus, Hg is concentrated at the periphery of the eye lens, which consists of the mitotically active lens epithelial cells. Throughout lens growth the epithelial cells continually divide and subsequently move inwards... High S content in the eye lens originates from the proteins (crystallins) rich in −SH groups and glutathione molecules present mainly in the lens epithelium. The fiber cells in the zebrafish lens core are arranged in concentric shells and thus the lens cross-section reveals the oldest tissue in the centre and the youngest at the outer rim. Due to the unique morphology and stability of the lens over the life of an organism, it has been suggested that the lens could potentially offer a historical record of Hg exposures affecting a fish through its lifetime...... The mechanism responsible for the preferential uptake of organic Hg in the eye lens epithelium is not known at present. However, since the overall development and morphology of the adult zebrafish lens is similar to that of other vertebrates, it may be hypothesized that a similar mechanism is also responsible for the accumulation of organic Hg in the mammalian eye."
Well, that is very interesting. If so, could some of the children with an autism diagnosis have more visible eye issues including color change to the eye lens? Could environmental mercury and more specifically, thimerosal, cause ocular and visual disturbances? Many researchers, including these, seem to think so:
Human Retinal Pigment Epithelium
"It is likely that melanosomes may continue binding metal ions throughout the life of an individual, ultimately reaching a concentration that is demonstrable."
Are the fair and susceptible canaries to the epidemic of autism revealing something about the internal progression to autism -- is it "ultimately reaching a concentration that is demonstrable," to lose eye contact, peek out of the corner of the eyes, spin objects, stare at ceiling fans, lose peripheral vision, have visual field constriction, develop eye color change and strabismus? When will those government and private organizations like CDC, NIH, NIEHS, IACC and Autism Speaks, with millions upon millions of dollars, investigate why this could be a sign of something ominous? Why are their researchers NEVER EXAMINING the PHYSICAL and MEDICAL issues of the children who have an autism diagnosis but instead COUNT bodies affected or hunt for du jour GENES that pay well in huge grants? Neither is helping the children or parents in the trenches of autism.
If mechanisms to environmental injuries can be stopped and existing ones treated then these investigations could HELP my daughter and so many others already affected and PROTECT others from harm. The authors of the Localizing organomercury uptake and accumulation in zebrafish larvae at the tissue and cellular level,above, HERE had a goal for their research-- " to have broad applications in vertebrate molecular toxicology including testing of new chelation therapy drugs."
Mercury accumulation in the squirrel monkey eye after mercury vapour exposure
"Mapping of the mercury distribution in the eye revealed that the non-myelin-containing portion of the optic disc was densely loaded with mercury deposits, which are mostly confined to the capillary walls and the glial columns....This finding indicates that mercury is trapped within the melanocytes, which keeps potentially dangerous material from reaching the neural retina. In addition, the retinal capillary walls were densely loaded with mercury deposits, even 3 years after exposure. It was also found that the inner layers of the retina accumulated mercury during a 3-year period. It is known that the biological half-time of mercury in the brain may exceed years. This seems also to be the case for the ocular tissue."
Are the eyes of autism possibly revealing a very big truth about a mechanism of injury?
Teresa Conrick is a Contributing Editor of Age of Autism.
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