Report on occupational diseases

An Australian Safety and Compensation Council (ASCC) document — Occupational Disease Indicators April 2008 — reports on the current trends of various diseases associated with occupations, providing credible baseline indicators in occupational disease.

Occupational disease is defined as: “All employment-related diseases which result from repeated or long-term exposure to an agent(s) or event(s) or which are the result of a single traumatic event where there was a long latency period.”

In May 2002, the Workplace Relations Ministers’ Council endorsed the release of the National OHS Strategy 2002-2012. Five national priority action areas were identified within the strategy. The Occupational Disease Indicators project supports the third priority area, to “prevent occupational disease more effectively”. ‘Occupational Disease Indicators April 2008’ is the second in a series of biennial reports, the first of which was published in April 2006.

Eight disease groups have been identified in consultation with stakeholders for monitoring:

• Musculoskeletal disorders
• Mental disorders
• Noise-induced hearing loss
• Infectious and parasitic diseases
• Respiratory disease
• Contact dermatitis
• Cardiovascular disease
• Occupational cancers

Data for the indicators published in this report come from National Data Set for Compensation-Based Statistics (NDS), National Notifiable Disease Surveillance System (NNDSS), Australian Institute of Welfare’s (AIHW) National Hospital Morbidity Database (NHMD) and AIHW’s National Cancer Statistics Clearing House (NCSCH).

Issues in occupational disease

Unlike injury, where there is usually a clear cause-and-effect relationship between a hazard and its health effect, most occupational diseases are multi-factorial in nature, with workplace exposures constituting one important part of the risk matrix. Many diseases, such as cancers and pneumoconioses, have long latency periods, while for other diseases, such as asthma, the link between cause and effect can be difficult to establish. This may lead to considerable under-reporting of occupational diseases.

For diseases with long latency periods, incidence rates based on workers compensation claims may not be the most appropriate indicator of emerging trends as reductions in exposure to disease-causing agents may not lead to any reduction in the incidence rate until many years later. Indicators based on exposures to disease-causing hazards are more appropriate. The ASCC is currently developing the Australian Hazard Exposure Assessment Database (AHEAD), aiming to collect, store and analyse workers’ exposure to disease-causing hazards, thus informing prevention initiatives and subsequently reducing the incidence of occupational disease. The ASCC will report on exposure data as it becomes available.

The indicators in the Occupational Disease Indicators report rely primarily on compensated claims data from the NDS. The data is complemented, where possible, by other data sources to increase the overall validity of the results. As the additional data sources (NHMD, NNDSS, and NCSCH) don’t identify work relatedness, data from these sources are only presented in this report for diseases with a high attribution to the work environment.

Trends in compensated claims for occupational disease are subject to a range of factors. For example, campaigns to increase awareness of occupational diseases may result in increased claims, while conversely, changes to legislation or standards may result in fewer accepted claims due to the application of higher acceptance thresholds. The main purpose of this data is in examining trends over time.

Summary of findings

From 1997–98 to 2004–05, decreasing trends were observed for five of the eight priority disease groups: musculoskeletal disorders, noise-induced hearing loss, infectious diseases, contact dermatitis and cardiovascular diseases.

Result Disease Findings

Musculoskeletal disorders — decreasing
The incidence of compensated claims for musculoskeletal disorders decreased over the time period assessed — the trend mainly driven by a decrease in muscular disorders rather than skeletal.

Mental disorders — increasing
The incidence of compensated claims for mental disorders increased over the time period assessed. While a slight decrease in the incidence rate was recorded for the most recent year, 2004–05, it is not clear whether this decrease will continue.

Noise-induced hearing loss — decreasing
Overall, the incidence of compensated deafness claims declined considerably over the time period assessed. Despite this, an increase was observed between 2002–03 and 2004–05. It is not clear whether or not this increase will continue.

Infectious and parasitic diseases — decreasing
The rate of compensated claims for infectious disease was quite volatile over the time period assessed; however, overall, a declining trend was observed. This declining trend was also observed when looking at disease notifications for specified zoonoses.

Respiratory disease — increasing
The rate of compensated claims for respiratory diseases trended upwards over the time period assessed. The rate of hospital separations due to respiratory diseases also increased over the same time period.

Contact dermatitis — decreasing
The rate of compensated claims for contact dermatitis declined considerably over the time period assessed.

Cardiovascular disease — decreasing
Over the time period assessed, the rate of compensated claims for cardiovascular diseases was quite volatile; however, an overall decline was recorded over the assessment period.

Occupational cancer — decreasing
The rate of compensated claims for cancer has risen over time; this appears to be due to persistent rises in claim rates for both skin cancer and Mesothelioma. NCSCH data shows that the rate of new cases of Mesothelioma being notified to cancer registries throughout Australia has increased dramatically since 1982, the earliest year for which data is available.

The full report is available from www.ascc.gov.au/ascc/HealthSafety/StatisticalReports/.

Australian Safety and Compensation Council