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Creating a Healthier Environment for Poultry Workers

by 5m Editor
16 June 2009, at 12:00am

Researchers in Canada have reviewed the effects of dust on the respiratory health of poultry workers in different types of poultry houses in the latest issue of <em>Journal of Occupational Medicine and Toxicology</em>. Jackie Linden summarises their key findings for ThePoultrySite.

Natasha Just and Baljit Singh of the University of Saskatchewan and Caroline Duchaine of Institut Universitaire de Cardiologie et de Pneumologie de Qu├ębec have published a paper in the new issue of Journal of Occupational Medicine and Toxicology, reviewing current knowldege on the effects of poultry house dust on the health of workers.

In their introduction, they explain that the Canadian poultry production industry contributes nearly $10 billion to the Canadian economy and employs nearly 50,000 workers. However, modern poultry facilities are highly contaminated with airborne dust.

They say that although there are many bioaerosols in the poultry barn environment, it is the endotoxin that is typically attributed with the negative respiratory symptoms observed in workers. They found that adverse respiratory symptoms are more prevalent in poultry workers than those working in other animal confinement buildings, and that those working in cage-housed operations facilities report a higher prevalence of some respiratory symptoms than those where the birds are kept on the floor.

In the paper, Just and her co-authors review the current state of knowledge on airborne dust in poultry barns and respiratory dysfunction in poultry workers while highlighting the areas that need further investigation. Their review focuses on the aerobiological pathway of poultry dust including the source and aerosolisation of dust and worker exposure and response.

Previous studies have found that dust levels are higher in floor system that houses with cages but that there was a tendency for the cage houses to have higher endotoxin levels, which has been linked to chronic phlegm in workers. However, the group points out that the two housing systems are not directly comparable because of differences in the age and type of birds kept in the house types, and the length of time workers spend in the houses.

There is evidence to support an adaptive response to endotoxin exposure in animal confinement workers.

The overwhelming evidence of the negative respiratory symptoms and immunological effects of poultry dust exposure suggests a need for remediation, say the researchers. They add, however, that many sources of dust, including some sources of endotoxin, are intrinsic to the poultry production industry and therefore, remediation is difficult. Measures that have been shown to be effective in controlling dust and ammonia levels include keeping poultry facilities clean, pelleted food, routine entry into buildings, use of lighting cycles, spraying water or oil and using respirators.

The Canadian researchers summed up the aerobiological pathway of dust in poultry facilities in Figure 1, indicating the factors relevant at each stage for poultry houses with cages or floor systems.

Figure 1. Aerobiological pathway of dust in poultry facilities
Common factors influencing each stage of the pathway are indicated in column 3, specific cage-housed factors are in column 2 and floor-housed factors are in column 4. Remediation opportunities for each stage of the pathway are indicated in column 1.
(adapted from Just et al., 2009)
REMEDIATION Floor-based Common Cage-based
RESPONSE
Can preventative measures result in workers being less responsive?
Can knowledge of 'healthy workers' identify new therapies?
Lower current and chronic cough; less reported wheeze Toxic fever, asthma-like syndrome, airway obstruction & hyperactivity, influx of inflammatory cells & cyotkines Greater current and chronic phlegm, higher reported shortness of breath
EXPOSURE
What exposures should be monitored?
What is an appropriate exposure limit?
Can exposure levels be lowered?
Greater total dust, lower endotoxin Particle size, aerodynamic diameter Endotoxin-enriched respirable fraction
AEROSOLISATION
Can aerosolisation be reduced?
Are new management practices necessary?
Type of litter, animal activity, stocking density, stationery feeders, young birds Temperature, humidity, ventilation, bird type, bird age, type of feed, time of day, air distribution Manure pits, animal mass, belt feeders, mature birds
SOURCE
Can any of the sources be removed?
Use of litter, moulting phase of young birds Poultry feed, droppings, skin flakes, feathers, bacteria, fungi, microbial components Presence of eggs, predominance of female birds

The researchers conclude that further understanding of the source and aerosolisation of dust in poultry operations will aid in the development of management practices to reduce worker exposure and response.

Reference

Just N., C. Duchaine and B. Singh. 2009. An aerobiological perspective of dust in cage-housed and floor-housed poultry operations. Journal of Occupational Medicine and Toxicology 2009, 4:13. doi:10.1186/1745-6673-4-13

Further Reading

- You can view the provisional version of the full report by clicking here.


June 2009