Features of Malignancy Prevalence among Children in the Aral Sea Region.

Objective: A study of primary cancer morbidity among children and subsequent calculation of average annual incidence were carried out for boys and girls, and young men and women in Kazakhstan. Methods: The investigated population lived in three areas of the Aral Sea region: designated catastrophe (Aral, Kazalt, Shalkar regions), crisis (Zhalagash, Karmakshy, Shiely regions), pre-crisis (Irgiz, Arys, Ulytau regions). Zhanaarka region of Karaganda oblast was applied as a control.

The Incidence of Malignant Tumors in Environmentally Disadvantaged Regions of Kazakhstan.

Objective: To explore the prevalence of malignant tumors in the adult population through 2003-2014 in parts of the Aral Sea region: a zone of ecological disaster, a zone of ecological crisis and a zone of precritical conditions. Methods: The long-time average annual levels of cancer morbidity stratified by zones of the Aral Sea region and trends of long-time average annual incidence indicators of malignant tumors were identified. Leading cancer localizations in the adult population was established and associations between cancer incidence and environmental pollution were analyzed.

Pro-oxidative interactions of cobalt with human neutrophils.

The primary objectives of this study were to investigate the effects of cobalt(II) chloride (Co, 1.5-25 microM) on the reactivity of hydrogen peroxide (H2O2, 100 microM) or oxidants generated by activated human neutrophils. The prooxidative interactions of Co with H2O2 or cells were measured by luminol-enhanced chemiluminescence (LECL), and according to the extent of oxidative inactivation of added alpha-1-proteinase inhibitor (API).

Radiologic abnormalities in South African mica millers: a survey of a mica milling plant in the Limpopo Province.

All 73 workers at a South African mica milling plant were surveyed for radiographic evidence of abnormalities related to dust exposures at work. Chest x-rays were taken and questionnaires administered to determine occupational and environmental exposure histories. Dust levels to which workers were exposed were measured.

Viability of mycobacteria in formalin-fixed lungs.

It is generally accepted that the risk of contracting tuberculosis is relatively high among medical laboratory workers and pathologists. Nevertheless, there is an assumption that once tissue is fixed in formalin, the risk for transmission and subsequent infection of mycobacteria is greatly reduced, if not altogether eliminated. To test the viability of potentially infectious mycobacteria in formalin-fixed tissue, tissue specimens from autopsy lungs fixed in formalin were cultured for mycobacteria.

Identification methods for Legionella from environmental samples.

Laboratories responsible for Legionella diagnostics around the world use a number of different culturing methods of non-equivalent sensitivities and specificities, to detect Legionella species in environmental samples. Specific countries usually standardize and use one approved method. For example, laboratories in Australia use the Australian Standard (AS) method and those in Europe, the International Standard method (ISO).

Aluminium uptake and excretion in potroom workers of a new primary aluminium smelter during the construction stage.

The aim of this study was to define bio-accumulation and excretion patterns of aluminium in newly employed potroom workers as well as changes in ambient aluminium levels in the potrooms of a modern aluminium smelter during the plant construction stage and one year into full production. A study was carried out on 115 newly employed volunteer potroom workers at various intervals, over a total period of 36 months. Before commencement of employment a structured questionnaire was completed by all study participants and the first collection of blood and urine specimens took place.

Asbestos lung fibre concentrations in South African chrysotile mine workers.

Mesothelioma has not been found in South African chrysotile miners and millers despite decades of producing about 100000 tons of the mineral per year. One possible explanation for the scarcity or absence of the cancer may be a relative lack of contaminating fibrous tremolite, an amphibole that variably occurs with chrysotile ores. The fibre content in the lungs of nine former chrysotile mine workers was ascertained by transmission electron microscopy.

Occurrence and causes of occupational asthma in South Africa--results from SORDSA's Occupational Asthma Registry, 1997-1999.

Objective: To present results for the first 3 years of the occupational asthma registry of the Surveillance of Work-related and Occupational Respiratory Diseases in South Africa (SORDSA) programme, ending December 1999.

Design: Surveillance was accomplished by collecting voluntary reports of occupational asthma cases from pulmonologists, occupational medicine practitioners and occupational health nurses.

Setting: Medical and occupational health referral centres in the nine provinces of South Africa.

Occupational respiratory diseases in South Africa--results from SORDSA, 1997-1999.

Objectives: To describe the nature and extent of work-related respiratory diseases reported to the national Surveillance of Work-related and Occupational Respiratory Diseases in South Africa (SORDSA) reporting scheme. The causative agents and industrial categories in which they occurred are also characterised.

Design: Voluntary monthly reporting of newly diagnosed cases by pulmonologists, occupational medicine practitioners and occupational health nurses.

Association between Chlamydia pneumoniae and atherosclerotic lesions.

There can no longer be any doubt that viable Chlamydia pneumoniae organisms are present in atherosclerotic lesions. Indeed, the endovascular presence of C. pneumoniae in coronary artery disease (CAD) is common.

Occupational health indicators for South Africa.

Indicators, statistics gathered from a larger pool because they have the power to summarize or to serve as indirect or proxy measures for information that is lacking, would be valuable in appraising occupational health status in a country provided data are both feasible and relatively inexpensive to collect. A generally accepted set of occupational health indicators does not exist. This project aimed to compile a set for South Africa.

Silicosis and tuberculosis: Part 2--a radiographic presentation of nodular tuberculosis and silicosis.

Indolent nodular pulmonary tuberculosis (TB) in workers exposed to silica dust may go undetected clinically and radiographically, especially in the absence of identification of tubercle bacilli in sputum. Illustrative cases demonstrating the radiographic manifestations of coexistent pulmonary silicosis and the indolent form of nodular TB are presented. Alterations in the usual chronologic progress, a rapid advance in nodular profusion or size outside the expected time frame, and distinct pattern alterations are features indicating the presence of TB associated with silicosis.

Occupational asthma as identified by the Surveillance of Work-related and Occupational Respiratory Diseases programme in South Africa.

Background: The nationwide Surveillance of Work-related and Occupational Respiratory Diseases in South Africa, SORDSA, was established in 1996 to provide systematic information on occupational respiratory diseases.

Objective: SORDSA's objectives are to monitor the nature, extent and distribution of occupational respiratory diseases, and to increase awareness of their diagnosis and prevention. This paper describes the programme and results obtained for occupational asthma in the first 2 years, ending in October 1998.

The ability of mineral dusts and fibres to initiate lipid peroxidation. Part II: relationship to different particle-induced pathological effects.

Exposure to pathogenic mineral dusts and fibres is associated with pulmonary changes including fibrosis and cancer. Investigations into aetiological mechanisms of these diseases have identified modifications in specific macromolecules as well as changes in certain early processes, which have preceded fibrosis and cancer. Peroxidation of lipids is one such modification, which is observed following exposure to mineral dusts and fibres.

Lung function prediction equations derived from healthy South African gold miners.

Objectives: To estimate lung function prediction equations and to identify appropriate normal reference values for the population of about 250 000 of South African gold miners.

Methods: Data from a lung function screening programme conducted at a large South African gold mine from 1994 to 1998 were used to estimate the lung function prediction equations. The most reliable period of lung function testing was identified in a previous study of a temporal pattern in reliability, and lung function tests from this period were used.

Silicosis and tuberculosis: a proposed radiographic classification of tuberculosis to accompany the ILO international classification of radiographs of pneumoconioses.

A significant proportion of workers exposed to silica dust are at risk of developing tuberculosis (TB). The higher the International Labor Organization (ILO) category of silicosis, the greater the TB risk. Subtle radiographic presentations of TB may be the initial manifestation of TB, particularly in the absence of sputum identification of TB bacilli.

Risk of mesothelioma from exposure to crocidolite asbestos: a 1995 update of a South African mortality study.

Objective: To find the risk of developing mesothelioma in a cohort born in 1916-36 in Prieska, Northern Cape Province, South Africa.

Methods: A birth cohort mortality study was carried out in a small town in the Northern Cape Province, South Africa, with a history of crocidolite asbestos mining and milling. The cohort comprised all white births registered in the magisterial district of Prieska from 1916 to 1936, inclusive (2390).

Chronic pulmonary function impairment caused by initial and recurrent pulmonary tuberculosis following treatment.

Background: A study was undertaken to establish the chronic effect of initial and recurrent treated pulmonary tuberculosis on impairment of lung function.

Methods: A total of 27 660 black South African gold miners who had reliable pulmonary function tests from January 1995 to August 1996 were retrospectively followed for the incidence of pulmonary tuberculosis to 1970. The lung function measurements in 1995-6 were related to the number of previous episodes of tuberculosis and to the time that had lapsed from the diagnosis of the last episode of tuberculosis to the lung function test.

The role of oxidative stress in diseases caused by mineral dusts and fibres: current status and future of prophylaxis and treatment.

Inhalation of silica and asbestos fibres by humans can lead to fibrosis of the lung and cancer. Different mechanistic approaches, including oxidative stress, are used for prophylactic and therapeutic interventions to attenuate the fibrogenic and carcinogenic effects of these particles. Thus far, most of these therapeutic interventions have been only partly successful.

Asbestos exposure and mesothelioma in South Africa.

Objectives: To describe the exposure experiences of South African mesothelioma cases, with emphasis on the contribution made to the caseload by different fibre types, the proportion of subjects with no recall of asbestos exposure and only environmental contact, and the importance of putative causes other than asbestos.

Design: A multi-centred case-control study.

Subjects And Setting: 123 patients with mesothelioma interviewed by trained interviewers in study centres established in Johannesburg, Kimberley, Pretoria, Bloemfontein, Cape Town and Port Elizabeth.

Allergy to complex salts of platinum in refinery workers: prospective evaluations of IgE and Phadiatop status.

Background: Experience has shown some variation in the associations between IgE, atopy, and sensitization to platinum salts. Clarification of these associations, and the value of the parameters in predicting and diagnosing sensitization of workers at risk, required prospective investigation.

Objectives: Evaluation of total IgE and Phadiatop(R) status to establish baseline values, and changes during employment, predictive or associated with subsequent platinum salt sensitization.

Human immunodeficiency virus and the outcome of treatment for new and recurrent pulmonary tuberculosis in African patients.

The purpose of this study was to evaluate the impact of human immunodeficiency virus (HIV) infection on treatment for tuberculosis (TB). The study population comprised 28,522 black Southern African gold miners. Patients with sputum culture-positive new or recurrent pulmonary TB diagnosed in 1995 were prospectively enrolled in the cohort.