Mercury Testing on Squamish Chlor-alkali Workers
1 January 2012
Mercury Analysis of Squamish Chlor Alkali Workers Blood, Hair and Urine
Jorma Jyrkkanen, 26 September 1979. Contact jjyrkkanen76@outlook.com
Introduction
In response to a request for chemical mercury Hg tests on the Squamish Chlor-alkali plant workers I activated Jyrkkanen Environmental Consulting and hired medical staff to participate in Clinical sampling. All costs were paid for by the workers themselves. The chemical testing was done by Chemex Labs of Vancouver using flameless atomic absorption. The work was done to establish baseline data for future reference at the behest of the clients. Confidentiality is assured by using code numbers for employees.
Results
A single control run was run on urine and blood using myself, the principle, which demonstrated my mercury was lower than 97% or the urine readings and 100% of the blood readings. Since I did not work at the plant, this is important albeit a small control.
Table 1, the Chemex results, reveals anomalous and some high readings in all 3 categories and especially in hair where 22% of the surveyed employees were above 20000 ppb. Urine tests were shown to be poor indicators of both present blood mercury levels and of body load as measured by protein bound hair levels though this is the primary method used to test employees. Residual adhesion mercury could have biased the results in the hair tests.
Table 1 ...cont
The coefficient of correlation r^2 for urine to blood was 0.058. R^2 for urine to hair was 0.20. Thus chance accounted for about 94% of the correlation between urine and blood and 80% between urine and hair. Blood and urine were highly correlated with r^2= 0.85.
A Student's t-test, alpha=0.05, one tailed, on blood mercury between Cell Room (CR) and Non-Cell Room (NCR) employees mercury levels supported the hypothesis that Cell room Employees had significantly higher mercury contamination, (P<0.01 **).
In Table 2, Blood and Hair CR mercury was highly significantly elevated (P<0.01**, ANOVA). A new statistic, the ratio of Blood to Urine Hg (B/U) was presented for the first time. It may have value in assessing kidney function the idea being healthy kidneys excrete lowering blood levels but showing high urine levels while damaged kidneys retain hence raising blood mercury levels but showing low urine levels. Ratio of CR (B/U) was also highly signifcantly elevated (P<0.05*, ANOVA).
P: Probability that the observed difference between Cell Room and Non-Cell Room mercury means were due to chance by ANOVA.
SX: A scalar indicating how much the Cell-Room Mercury readings were above the Background.
#2. In D'Itri and D'Itri (1977) #3, 4. After Jacobs (1964) #5. Obtained by dividing blood Hg/urine Hg.
What then are acceptable background levels of mercury? I present Tables 3,4,5 with some of the opinions offered by the literature for comparison and provide the equivalent values in ppb units except in the volumetric equivalencies.
Simply using averages from industrial and non-industrial cities is meaningless unless years of exposure and customs like fish eating are also assessed for compared for contribution.
Discussion and Analysis
When the ratio was plotted against months service a sharp split occured in the data trends at ratio (B/U)=1.5. A full 83% of employees B/U ratios seemed to be declining with months service indicating perhaps reduced ability of the kidneys to excrete or shunting of mercury to the protein bound form for excretion or perhaps acquisition of a job outside the Cell Room. More work was needed to ascertain which was which.
I plotted the Blood to Hair regression to see the shape of the relationship between them and it was quite good after a log squareroot transform of the hair mercury (Fig 1). Thus taking hair samples or blood samples can be used to infer the other from this chart, but with a large variance factor. If sample data do not fit this curve it may indicate a problem with Hg metabolism in that patient.
Regarding the B/U ratio analysis I conducted, I received a letter about the ratio B/U from a metals poisoning expert at St. Pauls hospital, Dr. John Ruedy, Head of the Dept. Of Medicine who also discussed it with Mr. Barry Clark and he says that while Hg related damage can occur to the kidney, excretion remains high through this venue despite the damage in his understanding (John Ruedy, 1979, pers. Comm.).
I infer from this that it damaged kidney excretion mercury is not likely to shunt to protein bound excretory pathways simply because of this experience and so my earlier logical deduction is probably not valid. In other words, mercury kidney damage cannot be inferred from higher blood or hair levels nor have I provided any evidence that such might occur.
Some Clincians feel urine levels of up to 30 ppb are normal. T. Suzuki (1977) feels that levels as low as 50 ppb are cause for concern. T. B. Eyl (1971) feels that 100 ppbs are cause for concern. This study suggests that urine tests should not be the only basis for determining body mercury load and excretion ability. Daily variation in readings occur so this is a matter which should be considered in sampling.
Epilogue
I cannot speak to the health effects of the observed levels in the client list, it being outside my biological consultants domain, a medical matter, between the employees and their personal physicians, society and health professionals.
Mercury is pervasive in our environment, being found in Marine fish like tuna, swordfish, water like many lakes in Ontario and in fish in those lakes like Pike and Pickeral, in dental amalgams, face creams, drinks, hand lotions, tanning solutions, tatoo inks and even the air we breathe. BC,s Pinchi Lake has returned high readings in Grebes frequenting the lake as I recall.
A gentleman living several kilometers from the Squamish FMC plant, asked me to come look in his gutter where I found a pool of metallic mercury condensed from the air in Town obviously wafted in from the plants air pollution. At night, the air cools over town and suspended mercury vapors from the mill condense and collect in places like eves troughs. In 2012 Canada started using mercury vapour light bulbs in a big way beccause they are more efficient and so it goes.
Symptoms of mercury can range from fatigue, nervous anxiety, insomnia, memory impairment, loss of appetite, head-aches, easy blushing, avoidance of friends, tremor in fingers, toes, eye lids and tongue, sores in the mouth, difficulty urinating, tightness and pains in the chest, coughing, difficulty breathing, vomiting, abdominal pain, occasional bloody diarrhea, severe kidney disease, numb lips, loose teeth, ataxia, pheumonitis, shivering, joint pains, icnreasing incoordination, AML like symptoms, loss of interest in sex, bitterness, manic depression psychosis, suspicousness, delerium with hallucinations, melancholia and last but not least, death. Mercury also causes Trisomy, a genetic condition leading to Klinfender's syndrome and Mongolism. How many of the mentally ill in hospitals and prisons and homeless on the streets are really victims of mercury pollution spirited away to avoid societal and corporate culpability?
This what we risk afflicting out citizens by ignoring mercury pollution. It can be expected to have even worse effects on animals in the effluents and discharge sheds of the world. Is mercury usage a very good idea? You decide. One consequence of this study, a very positive one, is that Dr. Sterling at SFU took an interest in it and established a Department of Industrial Toxicology. Thank you SFU, one of my old Alma Maters.
References
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