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PubMed1976

Effect of thiocyanate on nitrite estimation and the cleavage of nitrosamines.

Thiocyanate or bromide increased the colour formed by nitrite reacting with sulfanilic acid and naphthylethylenediamine. If the colour reagents were added together with thiocyanate (final concentration, M/10), the colour intensity was doubled. If sulfanilic acid was added three minutes before addition of naphthylethylenediamine, the relationship between nitrite concentration and colour production was more linear in the presence of thiocyanate. This effect was due to thiocyanate catalysing the diazotization of sulfanilic acid and inhibiting the reaction of nitrite with naphthylethylenediamine. Bromide and thiocyanate are similar in their catalytic effects on nitrosation, and hydrobromic acid in glacial acetic acid is an effective reagent for denitrosation of nitrosamine. Although thiocyanate catalysed denitrosation of nitrosamines, the effect was small except with nitrosomethylaniline, which had also been found to be denitrosated by sulfanilic acid. Thiocyanate could not be used generally for the destruction of nitrosamines; it was also found to be ineffective as an alternative to hydrobromic acid in the estimation of nitrosamines.

Acetates↗
PubMed2006

Serum thiocyanate levels in smokers, passive smokers and never smokers.

OBJECTIVE: To compare the serum thiocyanate levels in smokers, passive smokers and never smokers. METHODS: Serum thiocyanate was analyzed on 135 self reported smokers, never smokers and passive smokers by UV-Spectrophotometry (Manual method of Bowler). RESULTS: The mean serum thiocyanate concentration (112 +/- 36.6 micromol/L) of smokers was significantly higher (p value < 0.001) as compared to passive (55 +/- 16.1 micromol/L) and never smokers (41 +/- 6.6 micromol/L). The serum thiocyanate of female smokers (133 + 28.7 micromol/L) was higher (p value < 0.05) than male smokers (103 +/- 36.3 miccromol/L). Serum thiocyanate showed 91% sensitivity, 80% specificity and 84% accuracy at > or = 60 micromol/L for smokers. CONCLUSION: Serum thiocyanate is significantly higher in smokers than passive and never smokers. Serum thiocyanate at > or = 60 micromol/L may be considered as cutoff value for distinguishing smokers from non-smokers for future studies.

Adolescent↗
PubMed1983

[Salivary, urinary and plasma thiocyanate in smokers and non-smokers].

Thiocyanate is a major metabolic product of hydrocyanic acid. Its concentration in the serum, urine and saliva of individuals with little exposure to hydrocyanic acid (i.e. non smokers) is very low. But about three fold higher concentrations of thiocyanate are found in the sera, urine and saliva of smokers as compared to non smokers, because of cyanide provided by cigarette smoke. The concentrations of thiocyanate in the three biological fluids studied were different and it appeared to be no correlation in the distribution of thiocyanate concentrations in these fluids when individual subjects were compared. Urinary and salivary concentration power showed decreased kidney excretion of thiocyanate in smokers. The appearance or the disappearance of thiocyanates in the saliva and the urine takes place slowly. The salivary or urinary levels of thiocyanates are therefore good indicators of chronic intoxication from tobacco because it is not very sensitive to daily variations in tobacco smoking; it reflects the slow transformation of cyanide as well as the final elimination of this ion from urine which is slowed down in smokers.

Adult↗
PubMed1993

Determination of thiocyanate anion as an organic derivative by gas chromatography.

A simple and sensitive gas chromatographic method has been established for the determination of biologically active thiocyanate anion as pentafluorobenzyl thiocyanate. The method is based on the partition of an ion-pair from the thiocyanate anion and a complex crypstand to a benzene layer for derivatization with pentafluorobenzyl bromide. The resulting derivative was analyzed by gas chromatography with electron capture detection. The quantitation range for thiocyanate anion was over 0.086 and 3.45 nmol. The detection limit of thiocyanate in 0.2 ml sample is about 34 pmol. The effects of several parameters such as base or acid, reaction time and the amount of pentafluorobenzyl bromide were evaluated for the optimization of partition and derivatization of thiocyanate anion. Application of the method to the analysis of thiocyanate in waste water and human saliva proved to be feasible.

Calibration↗
PubMed2001

Validation of self-reported smoking status by simultaneous measurement of carbon monoxide and salivary thiocyanate.

OBJECTIVE: The objective of this study was to determine the validity of tobacco questionnaires when using as gold standard either a single biomarker or a combination of two biomarkers. METHODS: The methods were self-reported smoking compared with salivary thiocyanate and expired carbon monoxide in a 1996, population-based, Swiss survey of 552 men and 565 women. RESULTS: Sensitivity of self-reported smoking relative to salivary thiocynate or carbon monoxide alone was low (38.2% for salivary thiocyanate > or = 100 mg/L, 56.4% for salivary thiocyanate > or = 150 mg/L and 62.6% for carbon monoxide > or = 9 ppm). When defining true positive smokers as people with high concentration of both salivary thiocyanate and carbon monoxide, overall, sensitivity was 88.6% and specificity was 87.2%. In women, sensitivity increased from 85 to 89% when removing subjects exposed to passive smoking. When excluding heavy smokers, sensitivity decreased to 63% in men and to 71% in women. Older women had tendency to misreport smoking. CONCLUSIONS: This comparison of questionnaire data with the simultaneous measurement of salivary thiocyanate and expired carbon monoxide indicates that valid responses can be obtained for self-reported, current smoking in population-based surveys. However, the validity of questionnaires can be underestimated if the gold standard (of exposure to tobacco smoke) is either high levels of carbon monoxide or high levels of salivary thiocyanate.

Adult↗
PubMed1984

Salivary thiocyanate in pregnant smokers: a comparison of two collection methods.

Two simple methods of obtaining a salivary thiocyanate sample were tested to determine (1) if salivary thiocyanate could adequately differentiate a group of pregnant women into smokers and nonsmokers and (2) whether the simpler collection method of having the woman spit directly into the container produced as good a measurement of smoking exposure as having the woman chew a dental roll. Results show that thiocyanate measured from saliva samples collected by either of the two tested methods discriminates smokers from nonsmokers among pregnant women. The method of spitting directly into the collection container resulted in as good a discrimination of smokers from nonsmokers as results from the more complicated method of having subjects chew a dental roll. Advantages of using the direct method in large research projects are discussed. This is the first documentation that salivary thiocyanate distinguishes smokers from nonsmokers during pregnancy. The salivary data are consistent with earlier observations of higher serum thiocyanate levels during pregnancy, suggesting that thiocyanate may be metabolized differently during this time.

Adolescent↗
PubMed2001

Urinary thiocyanate levels as a biomarker for the generation of inorganic cyanide from benzyl cyanide in the rat.

A colorimetric procedure was developed and validated for the determination of thiocyanate in rat urine over the concentration range of 7-7000 microg/ml. It was applied to the determination of thiocyanate following its oral administration to male and female rats. The mean percentage urinary recoveries of sodium thiocyanate given by oral gavage at 10 and 100 mg/kg were 60 and 39%, respectively, for male rats and 89 and 73% for females over a period of 3 days. Most of the elimination occurred in the 0-48-h period post-dosing but significant amounts were still being excreted in the 48-72-h period. It was concluded from these results that the recoveries of urinary thiocyanate were such that this anion was suitable for use as a biomarker for the release of cyanide from organonitriles such as benzyl cyanide. Benzyl cyanide (150 mg/kg) administered orally to rats led to markedly increased urinary thiocyanate levels; for male rats this was equivalent to 54% of the dose and for females this was 65% over a period of 3 days. When adjusted for incomplete recoveries of the marker, thiocyanate, these values equated to 61 and 89%, respectively. It was concluded that this validated assay could be used to assess cyanide release from topically applied fragrance organonitriles (Potter, J., Smith, R.L., Api, A.M., 2000. An assessment of the release of inorganic cyanide from the fragrance materials, benzyl cyanide, geranyl nitrile and citronellyl nitrile applied dermally to the rat. Food and Chemical Toxicology 39, 147-151).

Acetonitriles↗
PubMed2001

Vicianin, prunasin, and beta-cyanoalanine in common vetch seed as sources of urinary thiocyanate in the rat.

When young rats were fed a diet containing common vetch seed for 1 month, they excreted in the urine approximately 7 times more thiocyanate than they had ingested. Vicianin, prunasin, and beta-cyanoalanine were identified as principal dietary sources of the excreted thiocyanate. Vicianin was isolated by chromatography and crystallization. Its structure was confirmed by mass spectrometry and by identification of its monosaccharides and aglycon. Prunasin was identified chromatographically by HPLC. The combined seed content of vicianin (0.68 micromol/g) and prunasin (0.16 micromol/g) corresponded to the cyanogen content of the seed (0.91 +/- 0.14 micromol/g; n = 7), determined as cyanide after autolysis. When vicianin was fed, the urinary thiocyanate output was 21% of the ingested amount of vicianin, whereas beta-cyanoalanine yielded a urinary thiocyanate output of < 0.2%. Calculations show that 73% of the thiocyanate can be derived from vicianin and prunasin, with 27% derived from beta-cyanoalanine. High urinary output of thiocyanate has been associated with endocrine and neurological disorders.

Alanine↗
PubMed1997

Effect of thiocyanate ingestion through milk on thyroid hormone homeostasis in women.

A thyroid-hormonal evaluation of thirty-five women consuming commercially packed milk containing thiocyanate was carried out. The mean serum thiocyanate concentration, which was measured by the FeCl3 colour test, was significantly higher (P < 0.01) than that of control subjects. Serum thyroxine (T4), triiodothyronine (T3) and thyroid-stimulating hormone (TSH) concentrations of exposed women were compared with those of thirty-five control subjects. Thiocyanate ingestion was associated with lower levels of T4 (P < 0.01) and higher levels of TSH (P < 0.01) compared with the control subjects. T3 was found to be higher in the women consuming thiocyanate-containing milk but the difference was not significant. The serum T4 level was found to be negatively correlated (r -0.359, P < 0.05) while the TSH level was positively correlated (r 0.354, P < 0.05) with thiocyanate concentration in the exposed group. From this study, it appears that ingestion of milk with added thiocyanate impairs thyroid function.

Animals↗
PubMed1986

Transfer of thiocyanate into chicken eggs.

Laying hens were fed thiocyanate (SCN) as a solution of potassium thiocyanate (KSCN) in their drinking water to determine whether dietary SCN was transferred into eggs. The thiocyanate content of their eggs was measured before and during thiocyanate administration. Egg thiocyanate content increased from 6 micrograms SCN/g albumen to 31 micrograms SCN/g (a 400% increase) in the period immediately following thiocyanate administration and then fell progressively, seeming to stabilize much closer to but still well above control levels.

Administration, Oral↗
PubMed1985

Effect of thiocyanate levels in milk on thyroid function in iodine deficient subjects.

To utilize the antibacterial effect of the lactoperoxidase system to prevent bacterial spoilage of raw milk it is necessary to increase the thiocyanate concentration of the milk. Thiocyanate has, however, a potent antithyroid effect which is enhanced by iodine deficiency. In this study the thyroid function has been studied, before and after 4 weeks daily administration of 250 ml of such treated milk, in 55 goitrous subjects living in an endemic goiter region of western Sudan. The iodine content was 0.1 mg/l and the thiocyanate content was either 3.6 mg/l (n 19) or 19 mg/l (n 36) in the milk. At the start of the experiment all subjects were iodine deficient with a urinary excretion of 40-50 micrograms/g creatinine. After 4 weeks daily intake of 4.75 mg of thiocyanate by way of milk the serum thiocyanate level increased by approximately 1.7 mg/l. Both at the beginning and at the end of the experimental period the serum levels of thyroxine, triiodothyronine and TSH were in the normal range for all subjects. After 4 weeks the TSH levels had decreased significantly, (from 2.6 +/- 0.2 to 2.1 +/- 0.2 mU/l, p less than 0.001) probably as an effect of the supplementary intake of iodine. The thyroid hormone levels remained unchanged during the experimental period. In conclusion, the intake of milk with an iodine concentration of 0.1 mg/l and a thiocyanate concentration of 19 mg/l does not have a negative effect on the thyroid function in iodine deficient subjects.

Adolescent↗
PubMed1979

Smoking during pregnancy--effects on the fetus and on thiocyanate levels in mother and baby.

Twenty-eight mothers smoking 10--20 cigarettes daily during pregnancy had significantly higher serum thiocyanate concentrations at delivery compared in 25 non-smoking controls. The thiocyanate levels were positively correlated to cigarette consumption and inversely correlated to the birth weights of the infants. A highly significant correlation existed between serum thiocyanate levels of the mother and umbilical cord serum thiocyanate levels, reflecting a nearly complete equilibration. The thiocyanate concentrations in human milk on the 4th day after delivery were considerably lower than the serum concentrations, and no correlation existed between serum and milk concentrations. The infants of smoking mothers had significantly decreased weight and length at birth compared in infants of non-smokers. Birth weights were 3 344 +/- 434 g and 3 620 +/- 504 g respectively (p less than 0.05), and lengths 49.8 +/- 1.7 cm and 51 +/- 1.6 cm respectively (p less than 0.05). No differences were found between smokers and non-smokers in placental and umbilical cord histology, and umbilical cord artery medial area. It is concluded that serum thiocyanate concentration in smokers may be used as an objective measure for smoke exposure, and that maternal cigarette smoking acts as an exogenous factor which interferes with intrauterine development of the fetus in a dose related way.

Birth Weight↗
PubMed1966

Inhibitory effect of saliva on glutamic acid accumulation by Lactobacillus acidophilus and the role of the lactoperoxidase-thiocyanate system.

Clem, W. H. (University of Washington, Seattle), and S. J. Klebanoff. Inhibitory effect of saliva on glutamic acid accumulation by Lactobacillus acidophilus and the role of the lactoperoxidase-thiocyanate system. J. Bacteriol. 91:1848-1853. 1966.-Saliva contains an antimicrobial system which inhibits the growth of Lactobacillus acidophilus, as well as a number of other organisms, in complete growth medium. This antimicrobial system consists of the salivary peroxidase (lactoperoxidase) and thiocyanate ions, and requires the presence of H(2)O(2). Saliva inhibits the accumulation of glutamic acid and certain other amino acids by resting cells. This effect of saliva is decreased by dialysis, and thiocyanate ions restore the inhibitory effect of dialyzed saliva. The inhibitory effect of saliva is decreased by heat (100 C, 10 min), and lactoperoxidase restores the inhibitory effect of heated saliva. Thus, the inhibition of glutamic acid accumulation by saliva appears to be due in part to the lactoperoxidase-thiocyanate antimicrobial system. H(2)O(2) increases the inhibitory effect of both saliva and the lactoperoxidase-thiocyanate system on glutamic acid accumulation. The inhibition of glutamic acid accumulation is not preceded by a loss in microbial viability. The glutamic acid accumulated by L. acidophilus under the conditions employed remains largely (over 90%) as free glutamic acid. This suggests that saliva and the lactoperoxidase-thiocyanate-H(2)O(2) system inhibit the net transport of glutamic acid into the cell.

Carbon Isotopes↗
PubMed1975

Thiocyanate ion formation in rapeseed meals.

Meal prepared from unheated rapeseed (Brassica napus cv. Zephyr) showed the presence of t,iocyanate ion, while meal from heated seed of the same cultivar did not show detectable amounts. Unheated seed meal on autolysis, and heated seed meal on incubation with thioglucosidase, yielded increased amounts of thiocyanate ion. Various commercial rapeseed meals showed the presence of t,iocyanate ion only after enzyme incubation. Low glucosinolate, cv. Bronowski, and higher glucosinolate, cv. Zephyr on enzymic incubation yielded comparable amounts of thiocyanate ion, suggesting that the precursor responsible in the two varieties was the same and present in similar quantities. No formation of thiocyanate ion was observed on incubation of sinigrin with thioglucosidase. Rats dosed with heated meal, containing intact glucosinolate, showed a slight increase of thiocyanate ion in the urine as compared with control rats dosed with water, while a relatively large increase followed dosing with sinigrin. Rats dosed with meal containing free thiocyanate ion excreted the ingested thiocyanate ion almost quantitatively.

Animal Feed↗
PubMed2002

Role of thiocyanate ion in metallothionein induction and in endogenous distribution of essential elements in the rat liver.

Thiocyanate is the major toxic metabolite of hydrogen cyanide, a toxic substance the organism may be exposed to as a result of cigarette smoking or industrial pollution. The complex interactions existing between metals and metallothionein induction are well known. However, the possible role of thiocyanate, which is also an anion, has not been established yet. Considering the interactions between metals and the metallothioneins, in this study the relationship between thiocyanate and the in vivo distribution of hepatic metallothionein and zinc, copper, iron, calcium, magnesium, and manganese are investigated in rats. This study implies that thiocyanate has, to some extent, an effect on the in vivo expression of metallothionein and endogenous distribution of essential elements in rat liver. Elevated levels of metallothionein and changes in hepatic concentrations of essential elements have suggested a role for thiocyanate in cellular metabolism and it might reflect a direct role of thiocyanate on alteration of cellular functional activities.

Animals↗
PubMed1990

In vivo prediction of extracellular and intracellular water in cattle and sheep using thiocyanate and urea.

Two experiments were conducted in cattle and sheep to determine the earliest time for thiocyanate equilibration with extracellular water. In Exp. 1, nine animals were infused to determine marker concentrations and sampling times. In Exp. 2, five steers were infused and then exsanguinated for tissue analyses. Thiocyanate equilibrated 22 to 31 min after infusion with a pool size equivalent to expected extracellular water. Plasma thiocyanate half-life averaged 29 h. Tissue concentrations 24 or 48 h after thiocyanate infusion were 20 to 24% of those observed in plasma for heart muscle and kidney and 6 to 8% in liver and skeletal muscle. A procedure is proposed for the in vivo estimation of empty body water (urea dilution), extracellular water (thiocyanate dilution) and, by difference, intracellular water in cattle and sheep, requiring only three blood samples, an initial sample and two samples taken 12 and 28 min after intravenous infusion of a urea-thiocyanate solution.

Animals↗
PubMed1996

Herbicide: fatal ammonium thiocyanate and aminotriazole poisoning.

OBJECTIVE: To describe fatal herbicide poisoning with Radoxone TL composed of aminotriazole and ammonium thiocyanate. CASE REPORT: A 54-year-old man was hospitalized because of unexplained coma with myoclonic jerks and vascular collapse. Despite symptomatic treatment with mechanical ventilation and vascular filling, life-threatening shock occurred with oliguria, profound metabolic acidosis and cardiac arrest. Hyperchloremia (141 mmol/L) with reversed anion gap (-19) suggested interference with chloride measurement caused by halogens (Br,F,I) or other anions such as thiocyanate. Eventually a weed killer, Radoxone TL containing ammonium thiocyanate, was found at the patient's house. Thiocyanate and aminotriazole blood levels were 750 mg/L and 138 mg/L respectively more than 12 hours after ingestion. After prolonged cardiopulmonary resuscitation, continuous venovenous hemodiafiltration was performed. Despite hemodynamic recovery the patient died 48 hours later of postanoxic coma. CONCLUSION: Aminotriazole, a systemic nonselective herbicide, is often associated with ammonium thiocyanate which enhances its activity. Experimental studies and previous fatal cases suggest a predominant toxicity of thiocyanate. Early diagnosis is important.

Amitrole↗
PubMed1991

Use of technetium-99m(V)thiocyanate to measure gastric emptying of fat.

Technetium-99m(V)thiocyanate was evaluated as a radio-pharmaceutical for measuring gastric emptying of fat. Olive oil was labeled with 99mTc(V)thiocyanate by direct extraction from acidic thiocyanate solution. After incubation with dilute HCl (pH 1.4) at 37 degrees C for 3 hr, approximately 5% of the total radioactivity eluted into the aqueous phase. When incubated with human gastric juice (pH 1.8 and 2.2), approximately 8% of the activity was detected in the aqueous phase at 3 hr. Scintigraphic studies performed in two rabbits showed that olive oil labeled with 99mTc(V)thiocyanate emptied slowly from the stomach, with a gastric half-emptying time (T50) of more than 3 hr. A low-nutrient soup labeled with 113mIn-DTPA and mixed with 99mTc(V)thiocyanate labeled oil was consumed by six human volunteers. The oil emptied much more slowly (p less than 0.02) (median T50 = 198 min) than the aqueous component (median T50 = 30 min). These observations indicate that 99mTc(V)thiocyanate is a suitable pharmaceutical to measure gastric emptying of extracellular fat.

Adult↗