Exposure to organic dust occurs in a variety of different environments that can be broadly categorized into agricultural environments, industrial environments, office buildings and residences. While many characteristics of these environments are similar, each has unique features which contribute to the potential exposure to organic dust. In each environment organic dust originates from different sources and is generated by different mechanical processes which affect dust composition, concentration, and particle size distribution. Work patterns vary in both duration and intensity for each environment and the population exposed may vary in their susceptibility to inhaled toxic substances. These factors bear upon the observed differences in health effects associated with exposure to organic dust in each of these environments.

1. (i). Outline the type of components occurring in organic dust from agricultural workplace environments.

(ii). Give four examples of only one type of component.

2. What are the variables that influence long-term exposure to organic dust in industrial workplace environment?

3. Explain briefly the major health effects of organic dusts on workers?

4. (a) Enumerate four specific industries which may have high exposure to organic dusts in Mauritius?

(b) (i) What do you understand by the term ‘pathogen'?"

(ii) Using a simple diagram, explain the classification of microbial pathogens according to the COSHH regulations.

(iii) list 10 occupations which are at increased risk from blood borne pathogens such as BBV.