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Mineralogical analysis of bronchoalveolar lavage in talc pneumoconiosis.

Bronchoalveolar lavage (BAL) fluid obtained from six talc workers with pneumoconiosis was studied by optical and electron microscopy for its mineral content. Two of these workers were mainly exposed to American and Australian talc, and the other four were exposed to French talc (Luzenac). In all lavage fluids, talc particles and talc bodies were abundant, sometimes many years after the end of exposure. A qualitative difference was the presence of tremolite asbestos fibres in the two patients exposed to American and Australian talc and its absence in the four French talc workers. The presence of tremolite in lavage is attributed to a geological association of this mineral with the inhaled talc. On the other hand, chlorite was abundant in BAL of the French talc workers. Hence, we suggest that bronchoalveolar lavage can confirm exposure to talc and provide information about the heterogeneity of inhaled dust.

Aged↗

Studies of respiratory morbidity in rubber workers. Part IV. Respiratory morbidity in talc workers.

Pulmonary function tests, chest x-rays, and respiratory questionnaires were administered to eighty talc workers and 189 non-exposed rubber workers from three rubber tire manufacturing plants. The talc workers, who were exposed to talc at levels below the current threshold limit value (TLV) of 20 mppcf for nonfibrous talc, had a statistically significantly greater prevalence of productive cough and of positive criteria for chronic obstructive lung disease (COLD) than did the control workers. The talc workers with more than 10 years of exposure had significantly decreased residual FEV 1.0. Multiple regression analysis of FEV 1.0 in the talc workers estimated that each year of exposure to talc dust reduced the FEV 1.0 by 26 ml. Talc workers had a clear increase in respiratory morbidity, despite the absence of chest roentgenographic changes. Based on this study, a safe exposure level for talc appears to be 25 mg/m3 as a time-weighted average.

Bronchitis↗

Talc-induced inflammation in the pleural cavity.

Talc administration into the pleural cavity induces pleurodesis. To obtain further insight into the inflammatory process that causes pleurodesis, the cellular kinetics in the pleural space after the administration of talc was studied, along with its relation to chemokine concentrations in the pleural fluid. Thirteen consecutive patients with idiopathic spontaneous pneumothorax and eight patients with malignant pleural effusions received talc pleurodesis. The first group was treated with talc poudrage, whereas the second group was treated with talc slurry. Pleural fluids were isolated before talc administration as well as 3, 6, 24, 48 and 72 h afterwards. The talc induced a rapid polymorphonuclear neutrophil (PMN) influx followed by an accumulation of macrophages. In addition, increased production of interleukin (IL)-8 and monocyte chemotactic protein (MCP)-1 was observed. The talc-induced PMN influx reached its maximum after 3-24 h, and was related to the IL-8 concentration. In contrast, the MCP-1 was not related to the macrophage accumulation. Talc-induced inflammation in patients with idiopathic spontaneous pneumothorax and malignant pleural effusion is characterized by an influx of polymorphonuclear neutrophils related to interleukin-8, followed by an accumulation of monocytes.

Adult↗

Lung damage in experimental pleurodesis induced by silver nitrate or talc: 1-year follow-up.

STUDY OBJECTIVE: To compare the lung damage caused by intrapleural silver nitrate (SN) with that caused by talc over a 12-month period. DESIGN: One hundred forty rabbits received an intrapleural injection of 0.5% SN or 400 mg/kg talc slurry in 2 mL saline solution. Groups of 10 rabbits were killed after 1, 2, 4, 6, 8, 10, or 12 months. The macroscopic pleurodesis, microscopic lung changes (ie, collapse, hemorrhage, and edema), and cellular infiltrates (number and proportion of cells) were graded on a scale of 0 to 4. RESULTS: The mean (+/- SEM) adhesion score after SN injection (3.3 +/- 0.1) was higher (p < 0.001) than that after talc injection (2.3 +/- 0.1). The mean alveolar collapse score was greater (p < 0.001) 1 month after SN injection (2.2 +/- 0.3) than after talc injection (0.2 +/- 0.1) and was similar from the second month on. The degree of parenchymal hemorrhage, by alveolar collapse score, (SN injection, 0.2 +/- 0.1; talc injection, 0.2 +/- 0.0) and edema (SN injection, 0.4 +/- 0.1; talc injection, 0.3 +/- 0.1) was minimal in both groups (p > 0.05). One month after the injection, the total number of inflammatory cells was greater (p < 0.001) in rabbits that had received SN injections (2.7 +/- 0.3) than in those that had received talc injections (1.2 +/- 0.1). From the second month on, cellularity decreased and became similar in both groups. The cellular profile was different, with a predominantly neutrophilic reaction after talc injection and a predominantly eosinophilic reaction after SN injection. CONCLUSIONS: Rabbits injected with intrapleural 0.5% SN had significantly higher scores for adhesions than did those that had received talc injections, with mild and reversible alveolar collapse and an eosinophilic responses, conditions showing a clear tendency to normalize with time.

Animals↗

Talc: understanding its manifestations in the chest.

Four distinct forms of pulmonary disease caused by talc have been defined. The first form, talcosilicosis, is caused by talc mined with high-silica-content mineral. Findings in this form are identical with those of silicosis. Talcoasbestosis closely resembles asbestosis and is produced by crystalline talc, generally inhaled with asbestos fibers. Pathologic and radiographic abnormalities are virtually identical with those of asbestosis, including calcifications and malignant tumor formation. The third form, talcosis, caused by inhalation of pure talc, may include acute or chronic bronchitis as well as interstitial inflammation; radiographically, it appears as interstitial reticulations or small, irregular nodules, typical of small-airway obstruction. The fourth form, due to intravenous administration of talc, is usually associated with abuse of oral medications and production of vascular granulomas manifested by consolidations, large nodules, and masses. Radiographic abnormalities associated with talc can be predicted when there is sufficient history of the nature of exposure, including the region of origin of the talc in cases of inhalation. Radiographic changes, such as diaphragmatic plaques, often attributed to both talc and asbestos have not been documented to be caused by talc alone. The author provides review of 18 well-documented cases.

Adult↗

Perineal talc exposure and epithelial ovarian cancer risk in the Central Valley of California.

Perineal talc use has been suggested as a possible risk factor for ovarian cancer based on its structural similarity to asbestos, a known human carcinogen. A population-based epidemiologic case-control study of epithelial ovarian cancer (EOC) was conducted in 22 counties of Central California that comprise the reporting area for 2 regional cancer registries. Telephone interviews were conducted with 256 cases diagnosed in the years 2000-2001 and 1,122 controls frequency-matched on age and ethnicity. The interview obtained information on demographic factors, menstrual and reproductive experience, exogenous hormone use, surgical history and family history of cancer. Questions on perineal talc use included frequency of use, duration of use and specific years when talc was used. Multivariate-adjusted odds ratio (OR) and 95% confidence intervals (CI) were derived from unconditional logistic regression. The OR for ever use of talc was 1.37 (CI = 1.02-1.85) compared to never users. However, no dose response association was found. Tubal ligation (TL) modified the effect of talc on EOC such that women with TL had an OR of 0.88 (CI = 0.46-1.68) associated with perineal talc use, whereas women with no TL had an OR of 1.54 (CI = 1.10-2.16). Talc use and EOC risk was highest in women with serous invasive tumors (OR = 1.77; CI = 1.12-2.81). This study provides some support for the hypothesis that perineal talc use is associated with an increased risk of EOC.

Adenocarcinoma, Clear Cell↗

Relation between structural characteristics of talc and its properties as an antisticking agent in the production of tablets.

Antisticking power varies according to the talc considered. Besides its chemical properties, it is necessary to assess its physical properties related to functionality. It is difficult to define the physical properties of talc implicated in its antisticking power. In this work, different talcs were characterised and their performance in reducing sticking in tablet manufacturing was evaluated. The following parameters were studied: apparent density, morphogranulometry, roughness, and the specific surface through the adsorption-desorption of argon. Next, the relationship between the characteristics of talcs and their antisticking power was considered. Talc before and after delamination-which is a way to obtain talcs with different physical characteristics-was compared. Antisticking power appeared to be dependent on the basal dimensions of talc, and on the ratio value of the external specific surface measured by diffractometry to the total specific surface by the BET method. Models to express the effect of textural factors of talc particles on antisticking power were defined.

Absorption↗

Thoracoscopic talc pleurodesis for the treatment of spontaneous pneumothorax.

BACKGROUND: During the Belgian Surgical Week in May 2004 some controversy existed on the optimal treatment of spontaneous pneumothorax. Doubts raised about the safety of talc in performing pleurodesis because of reported complications. METHODS: A retrospective analysis of a consecutive series of thoracoscopic pleurodesis with talc was performed. Patients operated for spontaneous pneumothorax were analysed focusing on complications and freedom of recurrence. A literature search was performed on complications from the use of talc to treat pleural disease. RESULTS: From September 1999 till August 2004 forty-one patients had a thoracoscopic pleurodesis with talc. In 21 patients this was performed for recurrent malignant pleural effusion and in 20 for spontaneous pneumothorax. In 5 of these 20 patients we faced a secondary spontaneous pneumothorax. In seven patients an apical pulmonary wedge resection of bullae was performed. No intra-operative or serious postoperative complications were seen in these patients. All drains were removed after 4 to 6 days. No episodes of respiratory insufficiency occurred. No recurrence was encountered during a mean follow-up of 22.7 months. CONCLUSION: Thoracoscopic talc pleurodesis for spontaneous pneumothorax was effective and safe in our experience. In the literature no convincing evidence against the use of talc to treat pleural disease was found. Although some cases of ARDS are attributed to the pleural administration of talc, the incidence of complications after talc poudrage appears to be low.

Adolescent↗

Superoxide anions in the pathogenesis of talc-induced cerebral vasocontraction.

We have recently reported that sustained contraction of the canine basilar artery induced by the intrathecal injection of talc (crystallized hydrous magnesium silicate) mimicked delayed vasospasm following subarachnoid haemorrhage. The present study aims to examine the pathomechanism underlying talc-induced vasocontraction, from the viewpoint of free radical theory, which has been established as a cause of delayed vasospasm. We estimated the effects of a prolonged intrathecal infusion of human recombinant Cu/Zn superoxide dismutase (hr SOD) on the contraction of the basilar artery caused by the intrathecal injection of talc in beagle dogs, which were assigned to the three groups: G1, sham operation with saline treatment; G2, talc injection with saline treatment; and G3, talc injection with 2 ml of hr SOD (7 x 10(4) U/ml) treatment. Talc administration resulted in the reduction in the angiographic calibre of the basilar artery by 63 and 61% on days 3 and 7 (G2). The treatment with hr SOD (G3) led to a significant attenuation of talc-induced contraction of the basilar artery on days 3 (P < 0.05 vs. G2) and 7 (P < 0.05 vs. G2). In the basilar artery wall of days 3 and 7 in G2, pathological changes such as myonecrosis, cytoplasmic vacuolation and detached intercellular junctions were observed. However, these pathological changes almost disappeared in G3. The present findings suggest that superoxide anions may initiate and/or mediate talc-induced vasocontraction and subsequent structural damage of the basilar artery.

Animals↗

Latex allergy from glove powder--an unintended risk with the switch from talc to cornstarch?

The present study aimed to investigate to what extent glove powders of different origins and brands bind and release latex allergens. One mineral talc and five cornstarch powders were used. The allergenic material was sap of Hevea brasiliensis. The powders were incubated together with the natural rubber latex sap, and four series of experiments were performed. The talc showed the highest tendency to bind isotope-labeled proteins. When incubated with a latex allergen solution, it reduced free allergen from 100 to 2 units/ml compared to a reduction to 70-98 units/ml for the cornstarch powders. In contrast to the nonstable binding of allergen to cornstarch, the binding to talc was irreversible. The allergen bound to talc was allergenically intact and, when incubated with serum, reduced the concentration of free IgE antibody to latex to 10% of the initial level. Mineral talc had a high capacity to bind latex allergens firmly. In contrast, cornstarch captured the latex allergen, but the binding seemed less pronounced and was unstable. The replacement of talc by cornstarch as glove-donning powder has coincided with the rapid increase in latex allergy. Mineral talc is heavy and only transiently airborne. Could this difference between talc and cornstarch in latex-allergen-binding pattern and the tendency of the latter to be airborne play an important role in the bioavailability of latex allergen and thus in the epidemic of latex sensitization.

Allergens↗

Systemic corticosteroids decrease the effectiveness of talc pleurodesis.

Corticosteroids can inhibit the inflammatory process and the formation of fibrosis. The purpose of this study was to determine whether the concurrent use of steroids at the time of talc-slurry pleurodesis would influence the development of the pleurodesis. One group of rabbits received an intrapleural injection of talc (400 mg/kg) and an intramuscular injection of triamcinolone (0.8 mg/kg) 1 d before talc instillation and weekly thereafter, whereas a control group received only talc. Ten rabbits in each group were killed at 6 h and at 1, 2, 4, 7, 14, and 28 d after instillation. The mean volume of pleural fluid was significantly lower in the group receiving corticosteroids at 6 h through 4 d after talc slurry than in the other groups. The degree of pleural adhesion was significantly smaller in the group receiving corticosteroids from Day 2 through Day 28. At Day 28, all 10 rabbits that received talc only had a pleurodesis score of 3 or 4, whereas only four of the 10 rabbits that also received steroids had a pleurodesis score of 3 or 4. This study shows that the use of corticosteroids at the time of talc-slurry pleurodesis markedly decreases the inflammatory reaction to the talc, and essentially prevents a pleurodesis from developing.

Animals↗

Transforming growth factor-beta2 induces pleurodesis significantly faster than talc.

Transforming growth factor-beta2 (TGF-beta2) has recently been shown to produce effective pleurodesis in rabbits. Conventional pleurodesing agents such as talc act by inducing pleural injury, which results in acute inflammation and fibrosis. TGF-beta2 is a profibrotic cytokine capable of producing fibrosis without inducing significant pleural inflammation. We hypothesize that intrapleural administration of TGF-beta2 would (1) produce an effective pleurodesis faster; (2) stimulate more collagen deposition, and (3) induce less inflammation when compared with intrapleural injection of talc. Thirty rabbits were divided into two groups and given either TGF-beta(2) (1.7 microg) or talc slurry (400 mg/kg) via a chest tube. Five rabbits from each group were killed at Days 1, 4, and 7. Gross pleurodesis was graded from 1 (none) to 8 (complete symphysis). The microscopic pleural inflammation and fibrosis were graded from 0 to 4. Pleural thickening and the total area of collagen deposition were compared. Intrapleural injection of TGF-beta2 produced effective pleurodesis within 7 d (median pleurodesis score = 7 at Day 7). At Day 7, TGF-beta2 induced significantly more collagen deposition (19.4 +/- 19.6% versus 4.6 +/- 2.9% of total area of pleura at Day 7), higher pleural fibrosis score (3.0 +/- 1.0 versus 1.8 +/- 0.5), and pleural thickness (286 +/- 191 versus 85 +/- 37 microm) than did talc. There was no difference in the degree of pleural inflammation between the two groups at Day 7 (2.6 +/- 0.9 for TGF-beta2 versus 2.4 +/- 0.6 for talc) or at any other time points. In conclusion, the intrapleural administration of TGF-beta2 produced excellent pleurodesis in rabbits at a rate faster than talc slurry and all other pleurodesing agents investigated before. TGF-beta2 stimulated more collagen deposition without inducing excess inflammation when compared with talc slurry. TGF-beta2 may have advantages over talc slurry in the management of recurrent pleural effusion and pneumothorax.

Animals↗

Talc slurry is an effective pleural sclerosant in rabbits.

Insufflated talc is probably the most effective agent for creating a pleurodesis both in the clinical situation and in animals. However, the insufflation of talc requires an invasive procedure such as thoracoscopy or thoracotomy. Recently, there have been reports that talc in a slurry was effective in the clinical situation. The objective of this project was to determine whether talc in a slurry at varying doses is an effective sclerosant in an experimental model in rabbits. Talc, 50, 100, 200, and 400 mg/kg, in a 2-mL slurry was injected intrapleurally through a small catheter in male rabbits. Eleven rabbits received each dose. Twenty-eight days after the instillation, the animals were killed. The pleural spaces were assessed grossly for evidence of pleurodesis and microscopically for evidence of fibrosis and inflammation. The degree of pleurodesis (on a scale of 0 to 4) after the injection of 50, 100, 200, and 400 mg/kg of talc was 1.1 +/- 0.9, 1.5 +/- 1.1, 2.7 +/- 0.6, and 3.4 +/- 0.5, respectively. The degree of microscopic fibrosis similarly increased with increasing doses of talc. These scores were similar to those we have reported with the tetracycline derivatives. In contrast to the results with tetracycline derivatives, none of the rabbits developed fibrothorax or hemothorax. From this study, we conclude that talc in a slurry is a very effective pleural sclerosant in rabbits and does not produce hemothoraces as do the tetracycline derivatives.

Animals↗

A comparison of thoracoscopic talc insufflation, slurry, and mechanical abrasion pleurodesis.

The purpose of this study was to compare the anatomic and histopathologic results of four different methods of pleurodesis in 10 dogs. Each animal was randomly assigned to receive two of the following methods of pleurodesis: thoracoscopic talc insufflation (poudrage), talc slurry administration, focal gauze abrasion by limited thoracotomy, and mechanical abrasion by thoracoscopy using a commercially available pleural abrader. Animals were killed 30 days after pleurodesis. At autopsy, the efficacy of pleurodesis was graded by evaluating the gross appearance of each pleural cavity and lung (pleurodesis score), and by determining the extent of adhesion formation (obliteration grade). Pleural and lung biopsy specimens were obtained from the areas most representative of adhesion formation for histopathologic evaluation. Pleurodesis scores (on a scale of 0 to 4) were 3.0 +/- 0.7 for talc poudrage (p < 0.05 when compared with talc slurry), 2.2 +/- 1.7 for thoracotomy, and 1.6 +/- 1.1 for talc slurry. Adhesions produced by gauze abrasion during thoracotomy were mostly peri-incisional. Thoracoscopic pleural abrasion using the pleural abrader was uniformly unsatisfactory. Granulation tissue formation was greatest in both talc models. The degree of parietal pleural thickening was greatest in the talc slurry model, but fibrosis and inflammation occurred mostly in gravity-dependent areas within the pleural cavity. Although differences were not statistically significant, thoracoscopic talc insufflation consistently produced the most widespread, firm fibrotic adhesions as evidenced by higher obliteration grades.

Animals↗

Talc pleurodesis : a controversial issue.

The use of talc for pleurodesis is a controversial issue. I have used talc in patients with malignant pleural effusion, recurrent pneumothorax, chylothorax and in selected cases of empyema. During pleuroscopy talc is insufflated through the lumen of the mediastinoscope. Up to 2 gr of purified talc is sprinkled under vision over the entire pleural surface. Of our total experience with 83 patients, 77 were available for follow up. Among 52 patients with pleural effusion, complete pleurodesis was achieved in 43 and partial pleurodesis in 5, with 4 failures. Of 21 patients with recurrent pneumothorax, complete pleural symphysis was achieved in 17 and partial in 3, with 1 failure. In all patients with empyema and with chylothorax, pleurodesis was complete. In total, obliteration of the pleural space was complete (excellent result) in 64 patients (83%) and partial (fair result) in 8 patients (10.5%). Talc failed to induced pleural symphysis only in 5 patients (6.5%). There were no complications and no deaths related to the procedure. This is attributed to the fact that only purified (British Pharmacopoeia) talc was used and its amount never exceeded 2 gr. The use of talc in pleura is safe and useful. It provides excellent palliation in patients with malignant pleural effusion and cure in the other groups. Excessive concern about complications of using talc is unjustified.

Adolescent↗

Comparison of insufflated talc under thoracoscopic guidance with standard tetracycline and bleomycin pleurodesis for control of malignant pleural effusions.

The standard palliation of malignant pleural effusions involves tube thoracostomy drainage with chemical pleurodesis. The insufflation of intrapleural talc under thoracoscopic guidance (n = 39) was evaluated against documented controls that consisted of patients (n = 85) who participated in a randomized study with tube thoracostomy drainage followed by either bleomycin or tetracycline sclerosis. Under local anesthesia, which was supplemented by intravenous sedation, patients in the talc group underwent complete pleural fluid evacuation. The talc was then insufflated evenly on the entire pleural surface under thoracoscopic guidance. Of the patients in the talc group who survived their disease process, 97% had a successful pleurodesis at 30 days and 95% at 90 days. In comparison, the bleomycin group demonstrated a success rate of 64% at 30 days and 70% at 90 days (p = 0.003 and p = 0.047 versus the talc group). The tetracycline group had successful pleurodesis in only 33% at 30 days and 47% at 90 days (p < 0.001 and p < 0.001 versus the talc group). There were only two patients in the talc group in whom pleurodesis was not successful, and both were subsequently found to have extraluminal compression of the right lower lobe bronchus, which prevented lung reexpansion. These data demonstrate that the insufflation of talc into the pleural cavity under thoracoscopic guidance is a safe and efficacious procedure in the control of malignant pleural effusions.

Adult↗

Talc in the liver of patients with chronic hepatitis C infection.

OBJECTIVES: The presence of talc crystals in the liver has been associated with prior history of i.v. drug abuse (IVDA). Patients with hepatitis C virus (HCV) infection often deny IVDA, and many patients have no other identifiable risk factors. To evaluate the role of prior surreptitous IVDA in patients with chronic HCV infection and to assess the role of talc identification in liver tissue, an epidemiological evaluation was performed. METHODS: One hundred and nine patients with chronic HCV (ALT abnormal > 6 months, HCV ELISA and recombinant immunoblot assay positive) underwent careful evaluation for risk factors potentially associated with HCV infection. All patients then had liver biopsy. Liver biopsies were reviewed by two observers to determine histological stage and were then examined by polarized light microscopy to reveal the presence or absence of typical talc crystals. Patients with discordance between history and histological findings were re-interviewed and were confronted with the information. RESULTS: Patient interviews revealed the following risk factors: IVDA, 17.1%; blood transfusion, 24.3%; possible household/occupational exposure, 14.4%; and tattoos, 15.3%. No identifiable risk factors were noted in 28.8% of the cohort. Talc crystals were seen in 9/109 (8.3%) of liver specimens. Of this group, only two patients admitted to prior history of IVDA. Seventeen patients with an IVDA history did not have identifiable talc crystals. Follow-up phone interviews were possible with five out of seven patients with liver talc who had previously denied IVDA history. Of the five patients, three admitted to prior IVDA but only after being confronted with the liver biopsy evidence. CONCLUSIONS: The findings of talc crystals in liver biopsy specimens appears to be a specific, but not a sensitive, marker for prior IVDA. Identification of talc crystals from liver tissue may contribute to categorization of risk factors in patients with community-acquired HCV infection. Tattoos are an important, and frequently unrecognized, risk factor for HCV infection. Despite these findings, a significant proportion of patients still have no identifiable risk factor for HCV acquisition.

Adult↗

An analysis of the National Toxicology Program's (NTP) Technical Report (NTP TR 421) on the toxicology and carcinogenesis studies of talc.

The NTP toxicology and carcinogenicity studies of nonasbestiform, cosmetic-grade talc (the NTP Talc Report) were conducted by exposing male and female F344/N rats and B6C3F1 mice to target aerosol concentrations of 0, 6, and 18 mg/m3 talc for 6 hr daily, 5 days per week. Based on results of the high dose, the Report concluded that talc caused lung tumors in female rats and pheochromocytomas in male and female rats, and there was no evidence of carcinogenic activity in mice. A thorough evaluation of lung toxicity revealed that talc-induced lung tumors occurred only in the group of animals that exhibited the most profound degree of chronic toxicity. However, these data were presented as empirical observations rather than discussed in a manner that would relate them to the risk assessment implications of the bioassay, i.e., relevant data were collected but not "used." In addition, the evaluation of the pheochromocytomas was inadequate because it failed to place sufficient emphasis on the spontaneous incidence of this tumor in rats. These deficiencies caused the author to vote against the conclusions presented in the Talc Report when it was reviewed by the NTP Board of Scientific Counselors. The appropriate conclusions are (1) the data do not indicate that the pheochromocytomas were treatment-related; (2) the maximum tolerated dose (MTD) was exceeded in the female rats exposed to the high dose; and (3) talc is not expected to cause lung tumors under conditions of exposure that fail to result in marked chronic lung toxicity.

Adrenal Gland Neoplasms↗