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The preparation of the 3,6-disubstituted dibenzosilole monomers , and by two different routes is described; Suzuki copolymerisation afforded poly(9,9-dioctyl-3,6-dibenzosilole) which has a sufficiently high triplet energy (2.55 eV) to function as a host for green electrophosphorescent emitters.

2,7-Disubstituted dibenzosilole monomers have been prepared by the selective trans-lithiation of 4,4'-dibromo-2,2'-diiodobiphenyl followed by silylation with dichlorodihexylsilane. Suzuki copolymerization of dibromo and bis(boronate) monomers afforded poly(9,9-dihexyl-2,7-dibenzosilole) which showed better efficiency than the corresponding polyfluorene in a single layer light emitting device. Preliminary studies demonstrated this to be a promising blue light emitting polymer.

There are established reporting schemes for some occupational and work-related illnesses but these schemes may underestimate the true incidence of such diseases. Not all cases may be referred to a participating physician and access to adequate diagnostic facilities are not always available. Collecting data directly from occupational health departments may overcome some problems related to under-reporting as they have good access to the entire working population within their company. The aim of this paper is to report the results from such a reporting scheme operated by a large multi-national engineering company during the period 1993-96. All UK sites of Lucas Industries (later LucasVarity) participated. A report form was completed by the occupational health department of each participating site each month. The report form gave abbreviated details of each case of occupational and work-related disease occurring at that site during the previous month. Forms were posted to a central office where the data was collated and analyzed. The incidence of respiratory diseases was broadly similar or slightly higher to that reported from other schemes. Musculoskeletal diseases were by far the most common category of disease reported. During a four year period of reporting the incidence of occupational and work-related diseases decreased overall by approximately 75%. As the reported incidence of respiratory disease was comparable with or slightly higher than that from other schemes, it appears that reporting schemes such as this can provide useful and accurate data. Musculoskeletal diseases are the most common type of disease attributed to work and should probably receive greater attention. The decrease in incidence seen in LucasVarity over time may reflect increased emphasis given to health and safety issues within the company during the reporting period.

Predicting the research needs within the engineering industry over the next 10 years requires a clear view of the industry's priorities and the role of the Occupational Health Practitioner in a rapidly changing and demanding world. This article describes the possible impact of manufacturing and social trends on occupational health practice and proposes priorities which favour operational requirements over fundamental scientific need.

In vivo tibia lead measurements of 20 non-occupationally exposed and 190 occupationally exposed people drawn from three factories were made using a non-invasive x ray fluorescence technique in which characteristic x rays from lead are excited by gamma rays from a cadmium-109 source. The maximum skin dose to a small region of the shin was 0.45 mSv. The relation between tibia lead and blood lead was weak in workers from one factory (r = 0.11, p greater than 0.6) and among the non-occupationally exposed subjects (r = 0.07, p greater than 0.7); however, a stronger relation was observed in the other two factories (r = 0.45, p less than 0.0001 and r = 0.53, p less than 0.0001). Correlation coefficients between tibia lead and duration of employment were consistently higher at all three factories respectively (r = 0.86, p less than 0.0001; r = 0.61, p less than 0.0001; r = 0.80, p less than 0.0001). A strong relation was observed between tibia lead and a simple, time integrated, blood lead index among workers from the two factories from which blood lead histories were available. The regression equation from two groups of workers (n = 88, 79) did not significantly differ despite different exposure conditions. The correlation coefficient for the combined data set (n = 167) was 0.84 (p less than 0.0001). This shows clearly that tibia lead, measured in vivo by x-ray fluorescence, provides a good indicator of long term exposure to lead as assessed by a cumulative blood lead index.

An epidemiologic screening survey was conducted in 325 male industrial workers to investigate the relation between serum total and ionized calcium concentrations and blood pressure. No relation was found. Previous reports of lower serum ionized calcium levels in hypertensive patients may be related to methodologic deficiencies both in the selection of subjects and in ionized calcium measurement. These data do not support the concept that increased blood pressure levels are related to calcium deficiency or to abnormal plasma calcium homeostasis.

The cancer mortality experienced by a cohort of 1807 workers from a semiconductor factory during the period 1970-82 has been investigated (as has cancer morbidity for 1970-81). Expectations for mortality were calculated on the basis of rates of mortality for the general population of England and Wales. Expectations for cancer incidence were calculated on the basis of incidence rates for the West Midland Region. For the total study cohort, observed numbers of deaths and incident cases for all cancers were close to expectation. For melanoma incidence, an observed of 3 cases was compared with an expectation of 0.68.