Assessment of lead exposure in indoor shooters in central Poland.

A steady increase in shooting practices is observed worldwide. Potential lead exposure at shooting ranges poses a risk to their employees and users, which is not widely reported outside of the USA, especially in Poland. Exposure to lead results from the use of bullets containing lead and the main route of exposure to this metal at shooting ranges is inhalation, i.e., during shooting or cleaning. The aim of this study was to assess lead exposure of employees and users in selected indoor shooting ranges in central Poland. Airborne lead concentrations at all locations in the shooting ranges were above Polish occupational exposure limit (OEL, 0.05 mg m-3). Elevated blood and urine lead levels, and decreased 4-aminolevulinic acid dehydratase activity (ALA-D) were found in subjects participating in shooting even for only a few (< 10) hours per week. Lead exposure at shooting ranges in central Poland, as indicated by elevated blood lead levels and decreased ALA-D activity, could represent an elevated risk for adverse health effects. Thus, information on the possible health consequences of lead exposure should be provided at these sites, and biomonitoring appears to be reasonable for regular workers and shooters.

Enhanced Biological Activity of a Novel Preparation of Lavandula angustifolia Essential Oil.

Lavandula angustifolia, one of the most popular medicinal plants, is the source of a bioactive essential oil characterized by a wide spectrum of biological activity, e.g., antiseptic, analgesic, and anticancer effects. In dermatology, the oil helps to relieve skin inflammation and exhibit wound healing potential. However, the mechanism of action of the lavender oil depends on its composition, which in turn is dependent on the origin and growing conditions. Our study aimed to compare the composition and proregenerative properties of the commercially-available narrow-leaved lavender oil produced in Provence, France, with the oil obtained from the narrow-leaved lavender cultivated locally in Poland. GC/MS analysis showed that self-manufactured essential oil had lower linalool content than commercial oil (23.2 vs. 40.2%), comparable linalyl acetate content (40.6 vs. 44%), while the proportion of lavandulyl acetate was significantly higher (23.2 vs. 5.5%). To determine the influence of lavender oil on the production of proinflammatory cytokines and proregenerative growth factors, gene expression of the selected signaling molecules by HaCaT cells was investigated using real-time PCR. Results showed a concentration-dependent effect of lavender oils on the production of IL-6, IL-8, and VEGF by the keratinocyte cell line. Finally, the potential of the lavender oil to increase the production of VEGF, the most important angiogenic factor, with the in-house preparation performing significantly better in the in vitro cell models was identified.

A Comparison of the Composition of Selected Commercial Sandalwood Oils with the International Standard.

Sandalwood oils are highly desired but expensive, and hence many counterfeit oils are sold in high street shops. The study aimed to determine the content of oils sold under the name sandalwood oil and then compare their chromatographic profile and α- and ß santalol content with the requirements of ISO 3518:2002. Gas chromatography with mass spectrometry analysis found that none of the six tested "sandalwood" oils met the ISO standard, especially in terms of α-santalol content. Only one sample was found to contain both α- and ß-santalol, characteristic of Santalum album. In three samples, valerianol, elemol, eudesmol isomers, and caryophyllene dominated, indicating the presence of Amyris balsamifera oil. Another two oil samples were found to be synthetic mixtures: benzyl benzoate predominating in one, and synthetic alcohols, such as javanol, polysantol and ebanol, in the other. The product label only gave correct information in three cases: one sample containing Santalum album oil and two samples containing Amyris balsamifera oil. The synthetic samples described as 100% natural essential oil from sandalwood are particularly dangerous and misleading to the consumer. Moreover, the toxicological properties of javanol, polysantol and ebanol, for example, are unknown.

[Analysis of volatile ingredients of selected essential oils listing relaxing action]. / Analiza lotnych skladników wybranych olejków eterycznych o dzialaniu relaksacyjnym.

BACKGROUND: Stress is a result of disturbed homeostasis and can contribute to the development of many diseases. One of the methods of combating stress is aromatherapy, which uses essential oils with a calming and relaxing effect. The aim of the work was to perform a qualitative analysis of selected essential oils with a relaxing effect. MATERIAL AND METHODS: The research concerned 6 preparations available on the Polish market, which are attributed with anti-stress activity. The qualitative analysis was carried out by gas chromatography with mass spectrometry, which allows the determination of both main and trace substances in the tested oils. The components of individual samples were compared with data from the literature. RESULTS: In the samples tested 9-36 substances were identified. The following substances had the largest share in the composition of the studied samples: limonene (0.5-91%), linalool acetate (16.8-39.2%), citronellal (0.1-28.7%), linalool (0.8-46.5%), valerianol (17.6%), geraniol (16.4%), and citronellol (14%). CONCLUSIONS: According to literature data, the main components of the studied essential oils have low acute toxicity. They can be safely used as intended and in the quantities recommended by the manufacturer. However, one should remember the potential synergistic effect (as a result of exposure to the abovementioned substances from various sources, such as: food, cosmetics, cleaning agents, etc.), as well as sensitizing effects of some compounds contained in oils. Despite the different chemical structure of active substances contained in the tested oils, it is suggested that the mechanism of the relaxing effect is identical and is associated with the inhibition of glutamatergic neurotransmission, similar to the action of benzodiazepines. Med Pr. 2019;70(2):229-47.

[Comparison of chemical composition of selected essential oils used in respiratory diseases]. / Porównanie skladu chemicznego wybranych olejków eterycznych stosowanych w chorobach ukladu oddechowego.

BACKGROUND: Essential oils are fragrances extracted from plants. They have a smooth consistency and pleasant smell. Essential oils have been applied in aromatherapy, cosmetics, food and pharmaceutical products. The aim of the study was to analyze the composition of selected essential oils used in respiratory diseases. MATERIAL AND METHODS: The qualitative analysis was performed by gas chromatography with mass spectrometry. For the study 6 essential oils available in Polish shops and used in various respiratory diseases were chosen. The results were compared with the information provided by the manufacturer and the literature. RESULTS: The method used in the presented work allowed to qualitatively identify the main components in studied essential oils. In the analyzed samples generally occurred: α- i ß-pinene, limonene, terpinen-4-ol and caryophyllene. In addition to limonene, the presence of linalool, eugonol and geraniol, potentially allergenic substances, were also detected. CONCLUSIONS: The qualitative composition of the studied essential oils comply with the existing literature data. Their main ingredients show antimicrobial and antiviral activities, therefore they are used to eradicate the symptoms of infection. However, the attention should be paid to the composition of the products because they often comprise potential allergens. Information on the presence of such a substance in the preparation should be clearly marked by the manufacturer on the packaging. Fragrances are also found in a number of household products that increase their concentration in the air of living premises, thereby increasing the risk of side effects especially in people with allergies or sensitive. Med Pr 2018;69(2):167-178.

Electrochemical treatment of tannery wastewater-Raw, coagulated, and pretreated by AOPs.

This study on tannery wastewater treatment showed that indirect electrooxidation by chlorine generated at a Ti/SnO2/PdO2/RuO2 (SPR) anode led to full ammonia removal, and a decrease in chemical oxygen demand (COD) of up to 77.0%. A combined process of coagulation + H2O2/UV + electrooxidation allowed us to achieve a decrease in COD of up to 97.5%. Equations describing the kinetics of the decrease in COD, the relationship between the decrease in COD and current, and the relationship between the current efficiency of COD reduction and the initial concentrations of the reagents were established. The changes in the Adsorbable Organically Bound Halogen (AOX) value were determined, and the individual compounds, including chloroorganics, present in raw and treated wastewater were identified by gas chromatography mass spectrometry (GC-MS). Values of AOX increased in the initial phase of electrooxidation, while afterwards they decreased.

[Testing of the composition of e-cigarette liquids - Manufacturer-declared vs. true contents in a selected series of products]. / Badanie skladu plynów do e-papierosów - deklaracje producenta a stan rzeczywisty w wybranej serii wyrobów.

BACKGROUND: Electronic cigarettes are currently in common use. However, in Poland there is no specific legislation governing the sale of these products. At the same time, no information has been made public about the hazards e-cigarettes pose to the users and bystanders - passive smokers. The aim of the study was to determine the qualitative composition of the analyzed liquid, which is an essential element of regulating the distribution of such cigarettes. MATERIAL AND METHODS: Under this study the method for determining the composition of e-cigarette liquids was developed. This method employs gas chromatography with mass spectrometry (GC-MS). Levels of nicotine and flavoring components were determined in 50 e-liquid samples. The results were compared with the information provided by the manufacturer on the packaging. RESULTS: The applied method of qualitative determination helped to identify the main ingredients, such as nicotine and propylene glycol (PG). Propylene glycol was found to be present in all liquids, because it was used as the solvent for nicotine and flavors. There was a good agreement between the declared and the determined content of nicotine in the analyzed samples. The agreement was considerably poorer for the remaining e-liquid ingredients, mainly flavors. CONCLUSIONS: There was no agreement between the flavor substances specified by the manufacturer and aroma identified in the e-cigarette liquid, which may pose a risk to users of e-cigarettes, particularly those susceptible to allergies. Several unsaturated aliphatic alcohols and aldehydes found to be present in the liquids, unstable at elevated temperatures, may be more harmful to the smoker than the original compounds. Therefore, it is essential to implement in Poland the legal provisions regarding e-cigarettes. Med Pr 2016;67(2):239-253.

Application of predictive models for estimation of health care workers exposure to sevoflurane.

OBJECTIVES: The aim of this study was to assess the potential use of predictive models to estimate professional exposure to chemicals in the workplace, such as the operating room, by simultaneous determination of the levels of exposure using a model and measurements. METHODS: Measurements included determinations of sevoflurane (SEV) in the workplace air of 117 operating rooms of 31 hospitals in one Polish region. Measurements were carried out at the time of various surgical procedures during administration of anaesthetics by endotracheal intubation. The measurement results were compared with the values estimated using two models: ECETOC TRA and Stoffenmanager. RESULTS: In one case the ECETOC TRA estimated the exposure concentration almost equal to the measured concentration but, because of the need to maintain a margin of safety in case of modelling, it can be concluded that the model underestimated the concentration. The Stoffenmanager model provided accurate exposure estimates in the examined case, and it can be used as a screening tool for the assessment of occupational inhalation exposure of medical personnel to anaesthetics. CONCLUSIONS: The results are of particular importance to the circumstances in Eastern Europe, where the levels of anaesthetics often exceed the relevant occupational exposure limits.

Health risk to medical personnel of surgical smoke produced during laparoscopic surgery.

OBJECTIVES: During laparoscopic cholecystectomy, the removal of the gall bladder, pyrolysis occurs in the peritoneal cavity. Chemical substances which are formed during this process escape into the operating room through trocars in the form of surgical smoke. The aim of this study was to identify and quantitatively measure a number of selected chemical substances found in surgical smoke and to assess the risk they carry to medical personnel. MATERIAL AND METHODS: The study was performed at the Maria Sklodowska-Curie Memorial Provincial Specialist Hospital in Zgierz between 2011 and 2013. Air samples were collected in the operating room during laparoscopic cholecystectomy. RESULTS: A complete qualitative and quantitative analysis of the air samples showed a number of chemical substances present, such as aldehydes, benzene, toluene, ethylbenzene, xylene, ozone, dioxins and others. CONCLUSIONS: The concentrations of these substances were much lower than the hygienic standards allowed by the European Union Maximum Acceptable Concentration (MAC). The calculated risk of developing cancer as a result of exposure to surgical smoke during laparoscopic cholecystectomy is negligible. Yet it should be kept in mind that repeated exposure to a cocktail of these substances increases the possibility of developing adverse effects. Many of these compounds are toxic, and may possibly be carcinogenic, mutagenic or genotoxic. Therefore, it is necessary to remove surgical smoke from the operating room in order to protect medical personnel.

[Assessment of occupational exposure of medical personnel to inhalatory anesthetics in Poland]. / Ocena narazenia zawodowego personelu medycznego na anestetyki wziewne w Polsce.

BACKGROUND: Despite common use of inhalatory anesthetics, such as nitrous oxide (N2O), halothane, sevoflurane, and the like, occupational exposure to these substances in operating theatres was not monitored in Poland until 2006. The situation changed when maximum admissible concentration (MAC) values for anesthetics used in Poland were established in 2005 for N2O, and in 2007 for sevoflurane, desflurane and isoflurane. The aim of this work was to assess occupational exposure in operating rooms on the basis of reliable and uniform analytical procedures. MATERIAL AND METHODS: The method for the determination of all anesthetics used in Poland, i.e. nitrous oxide, sevoflurane, isoflurane, desflurane, and halothane, was developed and validated. The measurements were performed in 2006-2010 in 31 hospitals countrywide. The study covered 117 operating rooms; air samples were collected from the breathing zone of 146 anesthesiologists, and 154 nurses, mostly anaesthetic. The measurements were carried out during various surgical operations, mostly on adult patients but also in hospitals for children. RESULTS: Time weighted average concentrations of the anesthetics varied considerably, and the greatest differences were noted for N2O (0.1-1438.5 mg/m3); 40% of the results exceeded the MAC value. Only 3% of halothane, and 2% of sevoflurane concentrations exceeded the respective MAC values. CONCLUSIONS: Working in operating theatres is dangerous to the health of the operating staff. The coefficient of combined exposure to anesthesiologists under study exceeded the admissible value in 130 cases, which makes over 40% of the whole study population. Most of the excessive exposure values were noted for nitrous oxide.

Chemical composition of surgical smoke formed in the abdominal cavity during laparoscopic cholecystectomy--assessment of the risk to the patient.

OBJECTIVES: The aim of this study was to assess the exposure of patients to organic substances produced and identified in surgical smoke formed in the abdominal cavity during laparoscopic cholecystectomy. MATERIAL AND METHODS: Identification of these substances in surgical smoke was performed by the use of gas chromatography-mass spectrometry (GC-MS) with selective ion monitoring (SIM). The selected biomarkers of exposure to surgical smoke included benzene, toluene, ethylbenzene and xylene. Their concentrations in the urine samples collected from each patient before and after the surgery were determined by SPME-GC/MS. RESULTS: Qualitative analysis of the smoke produced during laparoscopic procedures revealed the presence of a wide variety of potentially toxic chemicals such as benzene, toluene, xylene, dioxins and other substances. The average concentrations of benzene and toluene in the urine of the patients who underwent laparoscopic cholecystectomy, in contrast to the other determined compounds, were significantly higher after the surgery than before it, which indicates that they were absorbed. CONCLUSIONS: The source of the compounds produced in the abdominal cavity during the surgery is tissue pyrolysis in the presence of carbon dioxide atmosphere. All patients undergoing laparoscopic procedures are at risk of absorbing and excreting smoke by-products. Exposure of the patient to emerging chemical compounds is usually a one-time and short-term incident, yet concentrations of benzene and toluene found in the urine were significantly higher after the surgery than before it.

[Intoxication or false-positive acetaminophen result of toxicological determinations? Two case reports]. / Zatrucie paracetamolem czy falszywie dodatni wynik analizy toksykologicznej? Opis 2 przypadków.

The aim of this study was to show the diagnostic procedure used in the two cases with false-positive serum acetaminophen results in suspected acetaminophen poisoning. The determination of serum acetaminophen were carried out using a UV/VIS spectrophotometer (Specord 40 Analytik Jena), coupled with an analytic computer station WinASPECT. The employed method of determination was based on the acetaminophen reaction with sodium nitrite, which yields yellow colour of solution in the presence of sodium hydrate. The intensity of the yellow colour depends on the concentration of acetaminophen in serum. The relationship between absorbance and concentration was linear at concentrations in the range 50-600 microg/mL, with relative standard deviation of +/- 2.1% and detection limit of 30 microg/mL. To confirm or reject the doubtful results of colorimetric assays, the serums of patients were measured with high performance liquid chromatography with mass spectrometry detection and gas chromatography with mass spectrometry detection. The analysis of presented cases leads to a conclusion that acetaminophen results should be confirmed either by scanning urine for p-aminophenol presence (which is a routine procedure in our laboratory) or by using a different method of measuring acetaminophen serum levels.

Unmetabolized VOCs in urine as biomarkers of low level occupational exposure.

OBJECTIVES: To compare the usefulness of determining unchanged forms of volatile organic compounds (VOCs), namely toluene (TOL), ethylbenzene (EB) and xylene (XYL), in urine with the effectiveness of the already used biomarkers of occupational exposure. MATERIALS AND METHODS: Surveys were conducted in two workplaces (paint factory and footwear factory). In total, 65 subjects participated in the study. Air samples were collected using individual samplers during work shift. Urine and blood samples were collected at the end of work shift. Urine samples were analyzed for unchanged compounds and selected metabolites, while blood samples were tested for unchanged compounds. VOCs in blood and urine were determined by solid phase microextraction gas chromatography (SPME-GC-MS). RESULTS: In the paint factory, the geometric mean (GM) concentrations of VOCs in the air ranged as follows: 0.2-4.7 mg/m(3) for TOL, 0.4-40.9 mg/m(3) for EB and 0.1-122.6 mg/m(3) for XYL. In the footwear factory, the GM concentration of TOL in the air amounted to 105.4 mg/m(3). A significant correlation (p < 0.05) was observed between VOCs in blood, urine and air. The regression analyses performed for paint factory workers showed that TOL-U and TOL-B were better biomarkers of exposure (r = 0.72 and r = 0.81) than benzoic acid (r = 0.12) or o-cresol (r = 0.55). CONCLUSION: The findings of the study point out that the concentration of unchanged VOCs in urine can be a reliable biological indicator of low level occupational exposure to these compounds.

The influence of thiamazole, lithium carbonate, or prednisone administration on the efficacy of radioiodine treatment ((131)I) in hyperthyroid patients.

INTRODUCTION: The effects of selected drugs (see below) on the efficacy of ((131)I) radioiodine therapy were examined. MATERIAL AND METHODS: The study involved 200 hyperthyroid patients, treated with radioactive iodine. They were divided into five groups (40 persons in each). In Group I - patients were administered (131)I and thiamazole; in Group II they were given - (131)I and lithium carbonate; in Group III they were given - (131)I only (the assumed absorbed dose - 150-200 Gy, the same as in Groups I and II, for which Group III was a control group); in Group IV they were given - (131)I and prednisone; and in Group V they were given - (131)I only (250-350 Gy, the same as in Group IV, for which Group V was a control group). Therapeutic results were analyzed after six months based on clinical and hormonal status. The evaluation also included effects of the initial hormonal status on the outcome of (131)I therapy in Groups II and IV (v. respective controls, i.e. Groups III and V); such analysis was not performed in Group I because all the patients in that group were initially hyperthyroid. RESULTS: In 145 patients (72.5%) the therapy with (131)I was effective. In 55 patients (27.5%) the therapy was ineffective. The application of thiamazole during the peritherapeutic period in patients treated with 131I reduced the effectiveness of radioiodine, while lithium carbonate had no effect on the therapy outcome. Prednisone increased the effectiveness of the therapy with (131)I. Normalisation of the initial concentration of TSH was advantageous for the (131)I therapeutic outcome only when the assumed absorbed doses of 150-200 Gy were applied, while being of no avail for doses above 250 Gy. CONCLUSIONS: The present results indicate the necessity of careful analysis of administered drugs in hyperthyroid patients while qualifying them to (131)I therapy. The initial concentration of TSH has no effect on the efficacy of radioiodine therapy in cases where absorbed doses are regarded to be ablative. (Pol J Endocrinol 2010; 61 (1): 56-61).

Effects of drugs on the efficacy of radioiodine (|) therapy in hyperthyroid patients.

The treatment of hyperthyroidism is targeted at reducing the production of thyroid hormones by inhibiting their synthesis or suppressing their release, as well as by controlling their influence on peripheral tissue (conservative therapy, medical treatment). Radical treatment includes surgical intervention to reduce the volume of thyroid tissue or damage of the mechanisms of thyroid hormone synthesis by radioiodine ((131)|) administration. Radioiodine ((131)|) is a reactor radionuclide, produced as a result of uranium decomposition and emission of ß and γ radiation. The therapeutic effects of the isotope are obtained by the emission of ß radiation. In the paper, the effects of administered drugs (antithyroid, glucocorticosteroids, lithium carbonate, inorganic iodine, ß-blockers) on the final outcome of radioiodine therapy in patients with hyperthyroidism are discussed.

Analysis of demographic and clinical factors affecting the outcome of radioiodine therapy in patients with hyperthyroidism.

INTRODUCTION: The influence of demographic and clinical factors on the outcome of (131)I therapy in hyperthyroid patients has been examined, based on a retrospective evaluation of results obtained in patients submitted to (131)I treatment at the Department of Nuclear Medicine and Oncological Endocrinology, Medical University of Lodz (Province Hospital, Zgierz). The goal of the study was to analyse such factors as the age and sex of patients, disease duration, as well as the hormonal status before (131)I application, which could have an influence on the effects of therapy with radioiodine (131)I. MATERIAL AND METHODS: The study involved 500 randomly selected patients with hyperthyroidism, treated with (131)I radioiodine. The following 3 groups were defined: group 1 - patients with multinodular goitre (MNG), n = 200; group 2 - patients with a single autonomous nodule of the thyroid (AFTN), n = 100; group 3 - patients with Graves' disease (GD), n = 200. The local ethics committee (in the Polish Mother's Memorial Hospital - Research Institute, Lodz) approved the study. RESULTS: The obtained results indicate that the efficacy of therapy with (131)I applied in patients with MNG, AFTN and GD does not depend on either patient sex or patient age. The length of antithyroid treatment before (131)I therapy onset does not appear to have any effect on the therapy outcome, and the baseline thyrotropin concentration seems to be significant only in the case of GD. CONCLUSIONS: The analysed demographic factors do not affect the outcome of (131)I therapy in hyperthyroidism.

DNA damage induced by nitrous oxide: study in medical personnel of operating rooms.

Occupational exposure to anaesthetics such as nitrous oxide (N(2)O) and halogenated hydrocarbons has been suggested to increase risk of genetic damage. However, the dose-dependency of genotoxic effects has not been unequivocally established and their relation to occupational exposure limit (OEL) remain obscure. In this study, the genotoxicity associated with occupational exposure to anaesthetics has been investigated in a group of 55 female nurses and 29 male anaesthesiologists active for at least 5 years in a working environment containing variable concentrations of N(2)O and halogenated hydrocarbons. 83 unexposed health care workers (52 female nurses and 31 male doctors) matched for age, gender, smoking habit and employment duration were included in the control group. Genotoxicity has been assessed using comet test. Concentrations of nitrous oxide, sevoflurane and isoflurane monitored by gas chromatography and mass spectrometry made possible to relate the extent of DNA damage to the level of exposure. Our results for the first time document a positive correlation between the DNA damage and the N(2)O levels in the ambient air. By contrast, no correlation has been observed between genotoxic effects and concentrations of sevoflurane and isoflurane. The extent of genetic injury was especially aggravated among nurses and anaesthesiologists exposed to N(2)O in concentrations exceeding OEL (180 mg/m(3)). We conclude that occupational exposure to N(2)O is associated with increased DNA damage and that the level of exposure plays a critical role in this regard.

Occupational exposure to nitrous oxide - the role of scavenging and ventilation systems in reducing the exposure level in operating rooms.

OBJECTIVES: The aim of this study was to assess the level of occupational exposure to nitrous oxide (N(2)O) in operating rooms (ORs), as related to different ventilation and scavenging systems used to remove waste anaesthetic gases from the work environment. METHODS: The monitoring of N(2)O in the air covered 35 ORs in 10 hospitals equipped with different systems for ventilation and anaesthetic scavenging. The examined systems included: natural ventilation with supplementary fresh air provided by a pressure ventilation system (up to 6 air changes/h); pressure and exhaust ventilation systems equipped with ventilation units supplying fresh air to and discharging contaminated air outside the working area (more than 10 air changes/h); complete air-conditioning system with laminar air flow (more than 15 air changes/h). The measurements were carried out during surgical procedures (general anaesthesia induced intravenously and maintained with inhaled N(2)O and sevofluran delivered through cuffed endotracheal tubes) with connected or disconnected air scavenging. Air was collected from the breathing zone of operating personnel continuously through the whole time of anaesthesia to Tedlar((R)) bags, and N(2)O concentrations in air samples were analyzed by adsorption gas chromatography/mass spectrometry. RESULTS: N(2)O levels in excess of the occupational exposure limit (OEL) value of 180mg/m(3) were registered in all ORs equipped with ventilation systems alone. The OEL value was exceeded several times in rooms with natural ventilation plus supplementary pressure ventilations and twice or less in those with pressure/exhaust ventilation systems or air conditioning. N(2)O levels below or within the OEL value were observed in rooms where the system of air conditioning or pressure/exhaust ventilation was combined with scavenging systems. Systems combining natural/pressure ventilation with scavenging were inadequate to maintain N(2)O concentration below the OEL value. CONCLUSION: Air conditioning and an efficient pressure/exhaust ventilation (above 12 air exchanges/h) together with efficient active scavenging systems are sufficient to sustain N(2)O exposure in ORs at levels below or within the OEL value of 180mg/m(3).

An evaluation of the value of first thyroglobulin determination in the diagnostics of metastases immediately following differentiated thyroid carcinoma surgery.

INTRODUCTION: Evaluation of the differential value of the first thyroglobulin (Tg) concentration, measured after thyroidectomy (Tx) but before thyroid remnant ablation, in patients with differentiated thyroid carcinoma (DTC) as a marker of either metastases or residual cancer (M). MATERIAL AND METHODS: Data from 517 patients with DTC after Tx, with follow-up > 1.5 year were analysed retrospectively. Patients in whom either the course of the disease was unclear or interference in the Tg test was possible (a-TgAb [+], Tg recovery < 80%) were excluded from the study. Finally, the data from 247 patients were evaluated (age: 14-79 years; 223 women, 24 men). The results of TSH, thyroid radioiodine uptake (T(up24)), thyroid remnant volume (V) and Tg in patients with diagnosed M (group M1; n = 35) were compared with the same parameters in patients with remission > 1.5 year (group M0; n = 212). The area under the ROC curve was calculated. The clinical decision limit of Tg level to be suggestive of metastases was determined by means of efficiency curve. RESULTS: Groups M0 and M1 did not differ from each other with respect to TSH concentration (median 49.7 mIU/l vs 44.3; p = 0.16) or thyroid remnant volume (1.4 vs 1.1 ml; p = 0.79). However, they did differ with respect to T(up24) (7.6 vs 3.2%; p = 0.01) and Tg (4.5 vs 96.7 ng/ml; p = 0.000000). Area under ROC for Tg was 0.78 +/- 0.05 (mean +/- s.e.m.). The decision limit of Tg for suspected M was determined at 38.1 ng/ml, Tg sensitivity was 0.57 (95%CI 0.39-0.74) and specificity 0.96 (95%CI 0.92-0.98). CONCLUSIONS: First thyroglobulin concentration, determined after thyroidectomy but before other treatment, is higher in patients with metastatic DTC than in patients without such metastases. This indicates that Tg level may be used as an early marker of either residual or metastatic DTC (even if thyroid remnants are present).