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PubMed1995

Talc slurry pleurodesis. Pleural fluid and histologic analysis.

Although talc slurry pleurodesis is effective for control of malignant pleural effusions and recurrent pneumothorax, the mechanisms of pleurodesis remain incompletely defined. We instilled 70 mg/kg of sterile asbestos-free talc slurry into the pleural space of New Zealand white rabbits and studied the inflammatory response at 1, 2, 3, 7, 15, 30, 60, 90, and 120 days by observing pleural fluid and histologic characteristics. Talc slurry caused mesothelial denudement and an exudative neurotrophilic pleural effusion that resolved after 48 h. A transient mononuclear vasculitis was seen within the lung at 1, 2, and 3 days after instillation. Pleural adhesions were minimal and did not increase in number over time. Talc was found outside of the pleural space in mediastinal lymph nodes (4 of 23 animals examined), kidney (1 of 6), and spleen (4 of 10). The predominant cause of pleurodesis with talc slurry instillation is an acute pleural injury similar to the tetracycline class agents.

Animals↗
PubMed1998

Effect of pneumothorax on pleurodesis induced with talc in rabbits.

OBJECTIVE: The purpose of this study was to determine if a small pneumothorax would influence the pleurodesis resulting from talc instillation. METHODS: Sixty rabbits received an intrapleural injection of 400 mg/kg talc slurry. One half also received 10 mL of air intrapleurally after the talc. Ten rabbits in each group were killed 2, 14, and 28 days after instillation. RESULTS: Two days after the injection, the mean volume of air in the animals that had received the air was 7.5+/-0.4 mL. There was no air present in any other rabbits. The volume of pleural fluid and the pleural fluid glucose, protein, cell count, and differential were similar in both groups on day 2, while the LDH level was significantly higher in the air group (p<0.05). The degree of gross adhesions and microscopic fibrosis was similar in both groups and increased with time. CONCLUSIONS: A small pneumothorax does not decrease the efficacy of talc pleurodesis in our experimental model. These results suggest that the presence of a small amount of intrapleural air is not a contraindication to talc pleurodesis in humans.

Animals↗
PubMed2004

Fluorodeoxyglucose positron emission tomography and CT after talc pleurodesis.

BACKGROUND: Talc pleurodesis is widely performed for the management of persistent pneumothorax or pleural effusion, particularly malignant effusions. However, there are very few data characterizing fluorodeoxyglucose (FDG)-positron emission tomography (PET) and CT findings after treatment. METHODS: We retrospectively evaluated the FDG-PET and CT studies of nine patients who underwent talc pleurodesis for the treatment of malignant pleural effusions or persistent air leak. RESULTS: FDG-PET studies were performed on average 22 months after talc pleurodesis, and the mean CT follow-up period was 25 months. There was moderate-to-intense plaque-like or focal nodular-increased FDG uptake in the pleura on PET with mean standardized uptake value of 5.4 (SEM, 1.2; range, 2.0 to 16.3). The FDG uptake was either diffuse (two patients) or focal (seven patients), and most commonly occurred in the posterior costophrenic angles (five patients), followed by the apical regions (three patients), anterior costophrenic angle (one patient), and the anterior chest wall (one patient). On CT, high-density areas of pleural thickening or nodularity (mean, 230 Hounsfield units [HU]; SEM, 23 HU; range, 140 to 380 HU) corresponded to regions of increased FDG uptake. These pleural foci had an average thickness of 1.2 cm and measured up to 8.2 cm (mean, 7.1 cm) in length. Rounded pleural nodules were as large as 3.1 cm (mean, 1.5 cm). CONCLUSIONS: Talc pleurodesis produces increased FDG uptake on PET and high-density areas of pleural thickening on CT that remain unchanged on serial imaging. When PET detects increased uptake in the pleural space, correlation with CT is recommended to detect the presence of pleural thickening of increased attenuation that suggests talc deposits rather than tumor.

Adult↗
PubMed1975

Animal experiments with talc.

Italian talc has been tested on rats using three routes, intra-pleural inoculation, inhalation and ingestion. Groups exposed to superfine chrysotile asbestos and untreated controls were included for comparison. In all the experiments animals were allowed to live out their lives. The intra-pleural inoculation of talc produced no mesotheliomas in contrast to eighteen produced by the chrysotile asbestos. After ingestion, one leiomyosarcoma occurred with Italian talc and one with chrysotile asbestos. Whether these tumours are a consequence of the feeding is uncertain. The inhalation studies demonstrated that with equal dosage, talc can produce a similar amount of fibrosis as asbestos. However, the chrysotile exposed rats developed lung adenomas, adenomatosis and an adenocarcinoma, whereas the only lung tumour seen in animals exposed to talc was a small adenoma, which may have been an incidental finding.

Animals↗
PubMed1992

[Biological evaluation of experiments in rats of Australian and Italian talc aggressiveness].

In order to evaluate biological effects of Austrian and Italian talc, pulmonary and hemolytic tests as well as pathomorphological examinations were performed. 120 Wistar rats divided into 5 groups were given intratracheally 50 mg of the examined talc dust suspended in 0.5 ml of 0.9 NaCl. The control group received one 0.5 ml dose of NaCl. The observation periods were 6 and 9 months. Then the biochemical tests for hydroxyproline content in the lung were carried out along with patho-morphologic tests to evaluate the fibrogenic activity of the talcs examined. In animals the intratracheal insufflation of talc dust causes inflammatory changes within the bronchi and lungs. On the basis of biochemical examination of lung homogenates, the differences in the hydroxyproline content were determined. After 6 months the symptoms of chronic inflammation and cellular modules developed. Within another 3 months the symptoms of chronic atrophic inflammation in the bronchi were observed and cellular modules containing dust particles were detected in the lung. Hemolytic test revealed a slightly higher degree of aggressiveness of the Austrian talc.

Animals↗
PubMed1992

Perineal exposure to talc and ovarian cancer risk.

OBJECTIVE: We sought to determine whether the use of talc in genital hygiene increases the risk for epithelial ovarian cancer. METHODS: We interviewed 235 white women diagnosed with epithelial ovarian cancer between 1984-1987 at ten Boston metropolitan area hospitals and 239 population-based controls of similar race, age, and residence. RESULTS: Overall, 49% of cases and 39% of controls reported exposure to talc, via direct application to the perineum or to undergarments, sanitary napkins, or diaphragms, which yielded a 1.5 odds ratio (OR) for ovarian cancer (95% confidence interval [CI] 1.0-2.1). Among women with perineal exposure to talc, the risk was significantly elevated in the subgroups of women who applied it: 1) directly as a body powder (OR 1.7, 95% CI 1.1-2.7), 2) on a daily basis (OR 1.8, 95% CI 1.1-3.0), and 3) for more than 10 years (OR 1.6, 95% CI 1.0-2.7). The greatest ovarian cancer risk associated with perineal talc use was observed in the subgroup of women estimated to have made more than 10,000 applications during years when they were ovulating and had an intact genital tract (OR 2.8, 95% CI 1.4-5.4); however, this exposure was found in only 14% of the women with ovarian cancer. CONCLUSIONS: These data support the concept that a life-time pattern of perineal talc use may increase the risk for epithelial ovarian cancer but is unlikely to be the etiology for the majority of epithelial ovarian cancers.

Adult↗
PubMed1989

[Spanish talcs for pharmaceutical use. Mineralogic, chemical composition, physico-chemical properties].

A study has been carried out on the possible pharmaceutical use of 4 spanish talcs by direct estimation of the mineral purity by means of X-ray diffraction techniques, chemical analysis and quantification of some physico-chemical properties. There is a high level of talc in the samples 2 and 4, except in the talc 1 and the talc 3, with a relatively high content of chlorides. Quartz, calcite, feldspar, smectite, inter-stratified phases, kaolinite, amphibole, muscovite and dolomite are other contaminating minerals. The negative effects of these minerals on the pharmaceutical use of the talc include changes in the physical properties (colour), in the chemical ones (contained in heavy metals) as well as in the physico-chemical ones (adsorption properties). The data concerning cation exchange capacity and total specific surface are slightly higher than those concerning the pure mineral, and this is due to the occurrence of some contaminating minerals.

Chemistry, Pharmaceutical↗
PubMed1985

[Pleural talc administration under thoracoscopy in the treatment of pneumothorax. Study of a series of 109 cases treated over a 3-year period].

There has recently been renewed interest in thoracoscopy. Among its indications we consider talc therapy for a pneumothorax particularly worthy of interest. We report the three year results obtained on a series of 109 pneumothoraces. The indication for thoracoscopy were considered either for a chronic pneumothorax (failure of drainage after 8 days) or for a recurrent pneumothorax. We perform this technique under local anaesthetic with talc therapy given direct vision on the macroscopic lesions encountered. Patients were in hospital for a mean of five days. The results were as follows: Lung appearance. Normal 19%-Dystrophic bullae and giant bullae 41%. blebs: 13%-a visible breach 14%-Diverse anomalies 13%. The immediate failures with talc numbered 6 (5%) each time from the chronic pneumothorax group. They were treated surgically. There were 7 recurrences after talc therapy, 5 were partial recurrences requiring no further treatment and two total relapses were surgically treated. The radiological sequelae appeared minimal. On 5 occasions pleural discomfort hindered the diaphragmatic movement, in the other cases the radiological sequelae consisted of discrete pleural thickening. 42 patients had respiratory function testing and no abnormalities were noted. The failures or recurrences in the talc treated patients were all in the recurrent pneumothorax and were only 13 cases (12%). Thus thoracoscopy is a treatment of choice in the treatment of recurrent pneumothorax, and often replaces surgery. In certain cases (pneumothorax in respiratory failure) it is only possible treatment.

Adolescent↗
PubMed1978

Role of talc and benzo(a)pyrene in respiratory tumor formation. An experimental study.

Biologic and morphologic alterations caused by repeated intratracheal instillations of talc, alone or in combination with benzo(a)pyrene (B(a)P), were studied in Syrian golden hamsters to determine the possible carcinogenic and cocarcinogenic effects of talc. Talc alone failed to induce respiratory tumors, granulomas or mesothelial proliferation, but when a mixture of equal quantities of talc with B(a)P was administered, papillomas, squamous cells carcinomas and undifferentiated tumors of the larynx, trachea and lungs resulted. It therefore appears that in the hamster, talc is devoid of carcinogenic activity in itself, but does affect the activity of polycyclic hydrocarbons.

Adenocarcinoma↗
PubMed1978

Persistent chylothorax. Treatment by talc pleurodesis.

Two patients with persistent chylothorax resistant to therapy by special diet, thoracenteses, and tube thoracostomy drainage were successfully treated by talc pleurodesis. In one patient with advanced lymphosarcoma involving pleura and mediastinal nodes, the chylothorax was managed by open thoracotomy and talc powder. The other patient developed chylothorax following resection of a thoracic aortic aneurysm. She was successfully treated by talc suspension introduced through a thoracostomy tube. Pleurodesis with talc should be considered only when the chylothorax persists after an adequate period of medical treatment and pleural decompression. Intrapleural instillation of talc through a thoracostomy tube should be successful if the chylothorax can be evacuated and the underlying lung fully expanded.

Chylothorax↗
PubMed2005

Interfacial-chemistry mediated behavior of colloidal talc dispersions.

Interfacial chemistry and rheological behavior of talc suspensions as a function of pH, talc solid content, and type and concentration of ions have been investigated using electrokinetic measurements, rheology, settling behavior, and solution analysis. Zeta potential measurements show a strong dependence on the pH history of the talc suspension that only occurs when the surface area (solid content) of the talc is high. Particle interactions measured through dispersion yield stress measurements show a similar dependence. Talc is a magnesium silicate mineral and the dependence seen in the electrokinetic properties in this study has been attributed to Mg(II) dissolution at low pH, and has been confirmed by solution analysis. At high solid content (>20 wt%), pronounced Mg(II) ion dissolution occurs at low pH values. Formation and adsorption of electropositive Mg(II) hydrolysis products occurs at high pH (>9), and these lead to zeta potential reduction and, at high solid contents, charge reversal. Particle interactions reflect the surface chemistry behavior. Consequently, for a freshly prepared suspension at high pH, the yield stress is lower compared to after the pH has been taken to 5 and subsequently increased.

Journal Article↗
PubMed2006

The influence of polymer structure and morphology on talc wettability.

Advancing water contact angles were measured on freshly cleaved talc faces as well as on talc particles. The intrinsic hydrophobicity of talc was shown to be due to the dominance of the apolar components of the work of adhesion. Polyacrylamides and polysaccharides adsorb onto the surface of talc, displaying strikingly different morphologies. Adsorbed amount, apparent layer thickness, and polymer structure control talc wettability.

Journal Article↗
PubMed1995

Management of recurrent malignant pleural effusions. The complementary role talc pleurodesis and pleuroperitoneal shunting.

BACKGROUND: Recurrent pleural effusions in patients with advanced cancer is a common problem that causes significant morbidity and can negatively affect patients' quality of life for their remaining months. Several palliative treatment options are available. METHODS: The results of a 10-year experience with 180 patients referred for the surgical palliation of their condition were retrospectively reviewed. Their mean age was 60 years (range, 20-90 years). One hundred and thirty-four patients (74%) had been treated before referral with one or more of the following modalities: repeated needle thoracocentesis (87 patients), tube thoracostomy (24 patients), chemical or biologic pleurodesis (22 patients), and pleurectomy (1 patient). One hundred and seventeen patients demonstrated full lung expansion at thoracoscopy/mini-thoracotomy and underwent talc pleurodesis, whereas the other 63 patients had the "trapped lung syndrome" and required the insertion of a pleuroperitoneal shunt (Denver, Biomedical, Inc). RESULTS: There were no intraoperative deaths and the early death rate was 5.9% for the talc pleurodesis group and 3.2% for the group that received shunts. The mean hospital stay for the patients receiving talc and shunts was 7.3 days (range, 3-15 days) and 5.9 days (range, 2-12 days), respectively. Follow-up data were available in 60% of the patients and showed that effective palliation was achieved in more than 95% of patients in each group. There were eight patients (12%) with blocked shunts (five requiring replacement or renovation and three requiring removal and open drainage) at 1 week to 4 months after insertion. Two patients (one from each group) required one further episode of treatment by thoracocentesis. The median survival for the talc and shunt groups was 4.9 months (range, 1-36 months) and 5.4 months (range, 1-53 months). Patients with effusions because of secondary breast carcinoma or lymphomas survived the longest. CONCLUSION: In patients with malignant pleural effusions in whom pleurodesis is precluded by limited lung expansion, effective palliation can be achieved by pleuro-peritoneal shunt insertion.

Adult↗
PubMed1989

Compaction properties of microcrystalline cellulose and sodium sulfathiazole in combination with talc or magnesium stearate.

The dynamic indentation hardness, tensile strength, bonding index, and brittle fracture index were employed to investigate the compaction properties of a plastic excipient, microcrystalline cellulose, and a brittle drug, sodium sulfathiazole, in combination with different levels of either magnesium stearate or talc. These parameters were also used to quantitate properties of various combinations of microcrystalline cellulose and sodium sulfathiazole in order to illustrate the effects of combining a plastic excipient and a brittle drug. It was shown that the tensile strength, indentation hardness, bonding index, and brittle fracture index for compacts composed of microcrystalline cellulose in combination with either talc or magnesium stearate generally decreased as the amount of talc or magnesium stearate was increased over the concentration range of 0 to 9%. Similar results were observed for admixtures of sodium sulfathiazole in combination with either talc or magnesium stearate. It was also demonstrated that the tensile strength, indentation hardness, and bonding index increased, and the brittle fracture index decreased, as the percent of microcrystalline cellulose was increased in a binary mixture of sodium sulfathiazole and microcrystalline cellulose.

Cellulose↗
PubMed1997

Mineralogical features associated with cytotoxic and proliferative effects of fibrous talc and asbestos on rodent tracheal epithelial and pleural mesothelial cells.

Inhalation of asbestos fibers causes cell damage and increases in cell proliferation in various cell types of the lung and pleura in vivo. By using a colony-forming efficiency (CFE) assay, the cytotoxicity and proliferative potential of three mineral samples containing various proportions of fibrous talc were compared to NIEHS samples of crocidolite and chrysotile asbestos in cell types giving rise to tracheobronchial carcinomas, i.e., hamster tracheal epithelial (HTE) cells, and mesotheliomas, i.e., rat pleural mesothelial (RPM) cells. Characterization of mineralogical composition, surface area, and size distributions as well as proportions of fibers in all mineral samples allowed examination of data by various dose parameters including equal weight concentrations, numbers of fibers >5 micron in length, and equivalent surface areas. Exposure to samples of asbestos caused increased numbers of colonies of HTE cells, an indication of proliferative potential, but fibrous talc did not. RPMs did not exhibit increased CFE in response to either asbestos or talc samples. Decreased numbers of colonies, an indication of cytotoxicity, were observed in both cell types and were more striking at lower weight concentrations of asbestos in comparison to talc samples. However, all samples of fibrous minerals produced comparable dose-response effects when dose was measured as numbers of fibers greater than 5 micron or surface area. The unique proliferative response of HTE cells to asbestos could not be explained by differences in fiber dimensions or surface areas, indicating an important role of mineralogical composition rather than size of fibers.

Animals↗
PubMed2004

Talc inhalation is a life-threatening condition.

A case of rapidly progressive disease and pulmonary hypertension due to chronic cosmetic talc inhalation is presented. Although an uncommon cause of pulmonary hypertension, talc, especially through intravenous administration, should be included in the etiology of parenchymal pulmonary hypertension. In our case talc inhalation was inadvertent, causing fulminant disease leading to the patient's death. To our knowledge, this is the first case of inadvertent talc inhalation causing death in adult patient.

Adult↗
PubMed1992

Talc pneumoconiosis: a pathologic and mineralogic study.

Seventeen cases of "talc pneumoconiosis" were examined pathologically and mineralogically to ascertain whether a true talc pneumoconiosis existed and also to compare these results in primary, secondary, and tertiary exposures. Mineralogic analyses were performed on wet tissue or tissue blocks by a variety of techniques, including analytical transmission electron microscopy and x-ray diffraction. Overall, the pathologic appearance of the tissues was similar in primary, secondary, and tertiary exposures, although ferruginous bodies and foreign body giant cells were not always present in cases caused by secondary exposures. Mixed dust fibrotic lesions were found in two cases in which there were substantial quantities of quartz present. There was great variation in the minerals found within the lung tissues. Several cases showed significant quantities of mica and kaolin in addition to talc. One case consisted predominantly of mica and in fact could be regarded as "mica pneumoconiosis"; this diagnosis was correctly attributed because of the mineralogic findings. Tremolite fibers were found in only two cases. Substantial quantities of crocidolite and amosite fibers were found in one case. This study shows that "talcosis" frequently represents disease associated with a variety of minerals and that talc is a common denominator. It shows also the usefulness of lung dust mineral analysis, particularly in secondary industries, for evaluating the cause of a pathologic reaction when exposures are especially complex.

Aged↗
PubMed1983

Cytotoxicity of talc for macrophages in vitro.

The cytotoxicity of seven specimens of respirable talc dust for mouse peritoneal macrophages in vitro was studied. All talcs showed modest but consistent macrophage cytotoxicity and would be expected to be fibrogenic in vivo. Available data suggest that under certain circumstances respirable talc can cause lung fibrosis in animal inhalation studies. As most of the talc specimens under investigation were of high purity it seemed unlikely that the cytotoxicity was due to the presence of small quantities of contaminating minerals.

Animals↗