1. Environmental diseases

2. 1.Air pollution 2.Tobacco smoking 3.Chemical injuries 4.Physical injuries

3. The term environmental diseases refers to lesion & diseases caused by exposure to chemical or physical agents in the ambient, workplace, and personal environments.

4. Environmental pollution Environmental pollution Air pollution: Air borne microorganisms have long been major causes of morbidity & mortality. More wide spread are the chemicals and particulate pollutants found in the air especially in industrialized countries. ِ A pollutant is an agent in the environment that cause disease in those who are exposed, thus agents that are naturally present but in abnormal quantities such as ozone may be considered as pollutant.

5. Mechanism of pollutant effects It may produce acute toxicity directly by induction of inflammation or necrosis or indirectly when an immune response cause hypersensitivity reaction. It may cause chronic inflammation & fibrosis. It may cause degenerative changes leading to organ malfunction as occur in CNS in children with chronic lead poisoning

6. Indoor air pollution According to AMA 50% of all illnesses are caused or aggravated by polluted indoor air. These pollutants can make the air quality less than desirable, there effects ranging from allergies to TB and they are actually the cause of death to an estimated 8.5 million annually.

7. Pollutants & effects Radon: The common source of radon is uranium that is found in the soil or on the rock on which the house is built Radon gas is colorless & odorless. It enters the house through cracks in concrete walls, floor

8. Health Effects of radon Major health effect associated with radon exposure is lung cancer. If person is smoker & has elevated radon level in home,the risk of lung cancer is increased

9. Biological contaminants Which include mold, bacteria, dust, mites & pollen. Mites grow in damp warm environments Humidity level in the home plays an important role in controlling the environment, that some biological contaminants grow & thrive in A save home humidity level is 30-50%.

10. Health effects They can trigger allergic reaction & asthma attacks. Symptoms include sneezing,coughing,dizziness, fever & digestive problems. Children & elderly are particularly susceptible to diseases caused by biological agents

11. Pesticides They are used in home for controlling pests such as insects & rodents. Other sources include contaminated soil or dust that finds its way into the house. Symptoms of exposure are headache,dizziness, muscle spasm, weakness and nausea.

12. Asbestos It was commonly used in buildings as insulation Its sources are pipe, textured paint & floor tiles. The asbestos fibers are too small to be seen with naked eye, they are inhaled & accumulate in the lung. It can cause lung cancer, mesothelioma,asbestosis. The symptoms will appeared years after exposure

13. Outdoor air pollution This is a real problem in the industrial areas.Smog (smoke+fog),the visible accumulation of air pollutants is particularly heavy in cities where coal combustion result in release of sulfur oxides into the air which increase morbidity & mortality especially in person with pre existing lung disease. Photochemical oxidant smog results when incompletely burned hydrocarbons release CO & CO2 & Nitrogen oxides.

14. The action of sun light on these primary pollutants leads to release of secondary pollutants including Ozone & free radicals. The pulmonary changes seen with various air pollutants range from minor irritation to fibrotic diseases to the induction of cancer.

15. Ozone Toxicity Low level of ozone may be tolerated to healthy individuals but are detrimental to lung function especially in individuals with asthma & emphysema and when combined with particulate pollution. Its toxicity relates to production of free radicals which injure epithelial cells along the respiratory tract

16. Sulfur dioxide and acid aerosols Are emitted by coal and oil fired power plants and industrial processes burning these fuels. Particles that are less than 10Mm in diameter are particularly harmful since they remain in the air stream to reach the air spaces where they are phagocytosed by macrophages and neutrophils causing the release of mediators resulting in respiratory inflammatory reaction. Larger particles are removed in the nose or are trapped in the mucociliary action.

17. CO poisoning It is an air pollutant and important cause of death from accidents & suicide. It binds Hb with high affinity & causes systemic hypoxia with CNS depression. It is an air pollutant and important cause of death from accidents & suicide. It binds Hb with high affinity & causes systemic hypoxia with CNS depression.

18. Tobacco Smoking Chemical substances : 3000-4000 * Lung : Chronic obstructive airway diseases. * CVS: Atherosclerosis. * Others : Oropharynx,Larynx, Esophagus, Pancreas & Urinary bladder.

19. Figure 8-6 Adverse effects of smoking: the more common are in bold face. Agents in smoke have a direct irritant effect on the tracheobronchial mucosa, producing inflammation and increased mucus production Agents in smoke have a direct irritant effect on the tracheobronchial mucosa, producing inflammation and increased mucus production Agents in smoke have a direct irritant effect on the tracheobronchial mucosa, producing inflammation and increased mucus production Agents in smoke have a direct irritant effect on the tracheobronchial mucosa, producing inflammation and increased mucus production Adverse effects of tobacco smoking

20. Polycyclic hydrocarbon. B-naphthylamine. Initiation Nitrosamine. Phenol derivatives. Promotion Ammonia. Formaldehyde. Irritation NO SO2 CO Nicotine Blood pressure and heart rate

21. Tobacco Smoking Tobacco consumption interacts with alcohol in multiplying the risk of laryngeal cancer and increases the risk of lung cancers from occupational exposures to asbestos, uranium, and other agents. Tobacco consumption is an important risk factor for atherosclerosis and myocardial infarction, peripheral vascular disease, and cerebrovascular disease.

22. In the lungs, in addition to cancer, it causes emphysema, chronic bronchitis, and chronic obstructive disease. Maternal smoking increases the risk of abortion, premature birth, and intrauterine growth retardation

23. Factors play a role in tobacco smoking: 1- Amount of daily smoking. 2- Tendency to inhale. 3- Duration of smoking habit.

24. Types of smoking A - Active. B - Passive (involuntary): It is responsible for 3000lung cancer death in each year in non smoking adults. Young children whose parents smoke in their presence are at a higher risk for respiratory infections such as pneumonia & bronchitis