Dust exposure and pneumoconiosis in a South African pottery. 1. Study objectives and dust exposure.

Abstract

Dust exposure and pneumoconiosis were investigated in a South African pottery that manufactured wall tiles and bathroom fittings. This paper describes the objectives of the investigation and presents dust measurement data. x Ray diffraction showed that the clays used by the pottery had a high quartz content (range 58%-23%, mean 38%). Exposure to respirable dust was measured for 43 workers and was highest (6.6 mg/m3) in a bathroom fitting fettler. Quartz concentrations in excess of 0.1 mg/m3 were found in all sections of the manufacturing process from slip production to biscuit firing and sorting. The proportion of quartz in the respirable dust of these sections was 24% to 33%. This is higher than is usually reported in English potteries. Four hundred and six (80%) of the 509 workers employed at the pottery were potentially at risk of occupational lung disease. The finding of large numbers of pottery workers exposed to unacceptable dust concentrations is not surprising as poor dust control was found in all six wall tile and sanitary ware factories surveyed by the National Centre for Occupational Health between 1973 and 1989. Dust related occupational disease can be expected in potters for many years to come.

Effects of occupational exposures and smoking on lung function in tile factory workers

“…Thus, kaolin could play some role for the observed adverse eVect on lung function related to tile dust exposure. However, a study of South African pottery workers (manufacturing both wall tiles and sanitary ware) showed that the clays used in the pottery had high quartz content, ranging from 23 to 58%, with a mean of 38% by X-ray diVraction (Rees et al 1992). The content of kaolinite ranged from 20 to 36%.…”

“…All these exposures were consistently related to reduced lung function, and statistically signiWcant dose-response with duration of exposure was detected. According to the factory records, kaolin was the main exposure of the workers, but based on the raw materials used as well as exposure data in previous literature (Rees et al 1992), it is obvious that the factory workers also had silica exposure. Unfortunately, we were not allowed to access the company's data on exposure concentrations or to measure dust concentrations in this factory.…”

The global burden of disease due to occupational carcinogens

“…However, there are few data on distribution of exposure values for developing countries. Using relevant data that could be obtained [Yin et al, 1987;Myers et al, 1989;Rees et al, 1992;Dosemeci et al, 1995;Partanen et al, 1995;NIOSH, 1999;NIOSH, 2000], partition factors were estimated for the A regions and for the B-E regions. For A regions, it was assumed that 0.90 of exposed workers had Low exposures (at/or below the PEL), and 0.10 had High exposures (above the PEL).…”

Respiratory Toxicity of Raw Materials Used in Ceramic Production

“…For instance, dust exposure and pneumoconiosis were investigated in a South African pottery. Xray diffraction showed that the quartz content of the clays used by the pottery ranged 23% to 58% and 80% of the workers employed were potentially at risk of occupational lung disease 2) . Similarly, based on radiographic evidence, cases of silicosis with a clear dose-response gradient for years of exposure as well as a significant reduction in Forced Vital Capacity (FVC) and Forced Expiratory Volume in the first second FEV 1 have been reported among ceramic and pottery workers in Italy 4,7) .…”

“…Employees of ceramic production, manufacturing of wall tiles and sanitary-ware potteries (i.e., manufacturer of china plumbing fixtures) are occupationally exposed to crystalline silica [1][2][3] . Long term inhalation exposure to dust during production of ceramic has been associated with elevated risk of pneumoconiosis, chronic bronchitis and ventilatory disorders among both male and female workers [4][5][6] .…”