Health problems

1. Health problems

2. Public Health Protecting the health of the general population is a fundamental goal of environmental technology

3. Main problems • polluted air • polluted water • polluted soil • radiation • noise

4. We can be hurted: • digestion (drink, food, washing tooth) • contact (skin) • respiration • hematogenious – via blood

5. Air Pollution sources: - point - line - area

6. Traffic • it’s near to the ground→we breath it • its volume is growing • emission: NOx, CO, CxHz • the faster a car goes: the lower CO and CxHz and the more NOxemissions are made

7. Traffic - 50-70 km/h would be optimal • can’t be used because of the safety: traffic lights pedestrians, bikers

8. Pollutants • anthropogenic: materials from burning (CO, CO2, NOx dust smog aerosol fibre (asbestos)

9. Pollutants • natural (biological): pollens CH4 dust Rn gas

10. Water • Water treatment : main aim is to avoid infections = eliminate pathogens (decrease their concentrations) - Pathogens = microorganisms causing health problems (Viruses, bacteria, protozoa)

11. Transmission of diseases: • Direct: contact or droplet spray • Indirect: • Airborne: aerosol, dust • Vehicle-borne: water, food, milk • Vector-borne: insects, animals

12. Infectious diseases Water-borne: Typhoid fever Cholera Infectious hepatitis Dysentery Insect-borne: Malaria Yellow fewer • Rodent-borne: • Typhus • Bubonic plague • Airborne: • Legionella

13. Increased importance of infections Change in ecosystem – new habitats Air conditioning Waste disposal sites Rodents – rats is sewage collection systems Change in human habits Urbanisation – high population density Public transport Global movement of people and goods Migration Export, import

14. Important factors Infectious dose: Amount of microorganisms causing health problem to one certain person Depends on: Type of microorganism (viruses: 1-2, bacteria: thousands) General health of person Physical condition Age Immune system

15. Important factors Virulancy: Ability to change according to the change in the environment Antibiotics – resistency, new variants Persistency in water treatment Resistancy against chlorine and other disinfecting agents – e.g. Clostridium

16. Soil • the groundwater will be polluted also - plants growing on the polluted area accumulate some pollutants

17. Radiation • Ionizing (radioactive) - a -b -g - neutron • not ionizing (electromagnetic)

18. Noise • Physical pricess • sense • Psychological process • periodic change of pressure in a point (oscillation) • individual

19. Noise • serious health problems, even if we cannot hear it • 30-40 dB – sleeping problems • 40-60 dB – feeling tired • 80 dB – demage of hearing

20. Reduction of noise • distance • plant-zone • other objects

21. Micropollutants • Causing health problems in very small concentrations (g/l) - organic - inorganic

22. Inorganic micropollutants • Heavy metals: Pb, Hg, Cd, Cr, etc. • Long lasting health problems in small concentrations • Problem: protein denaturation • Aminoacids contain S – heavy metals bind to S • Enzime (protein) can not work • Biodegradation is blocked • Different matters accumulate • Limiting values for drinking water, treated sewage, sewage sludge, etc.

23. Heavy metals Cd • Itai-itai illness • From metal mine (heavy rains) – solid form • River sediment – floods • Rise production – anaerob environment • Became soluble • Deformation of bones (Ca-Cd)

24. Heavy metals Hg • Minamata Bay – Japan 1950 • Mercury compound (in solid form) – discharged to the sea (HgSO4 – catalizator) • Reductive (anaerob) environment, bacteria, B12 vitamine • Transformation to HgS, then methylmercury [CH3-Hg]+ • Accumulation in fish – and in people • Death, blindness, paralysis, irritation, depression

25. Organic micropollutants • rock oil and its spin-offs • detergents • pesticides: DDT, herbicides, fungicides • PCBs, PAHs Lots of them has been banned from use (DDT, PCB)

26. PCB • Polychlorinated biphenyls (organic, aromatic, containing chlorine) • 200 compounds: C12H10-nCln • Oily substance - synthetic • Used in paints, electrical transformer fluids, rubber, cooling fluid • Non biodegradable (because of Cl) • Accumulate in river sediments • Toxic to Daphnia (0.2 mg/l), to fish (2 mg/l) • Causing death, cancer

27. DDT • Chlorinated hydrocarbons • Toxic to animals (contact, oral, inhalation) • More chlorine, more effective the chemical – less biogedradable • Accumulation (soluble in fat, non-soluble in water) • Concentration can increase to 10000* • Nerve toxin, cause death, paralysis - Still found in the body tissues of animals (Antarktis)

28. Toxicology Studies the effect of chemicals that are harmful or fatal when consumed by organisms in relatively small amounts - Toxic - Carcinogenic - Mutagenic - Teratogenic

29. Toxicology • Acute (immediate) • Chronic (long-lasting) LD50, LC50 • Lethal dose/concentration 50% • The dose when 50% of the test animals dies

30. Toxicology - Correlation between environmental factors and the health of humans/other organisms - One parameter sholuld be changed while others are the same – experiments needed

31. Toxicology - Humans can not be tested directly - Toxicology tests: bacteria, algae, Daphnia, fish, rats, etc. - acute (48-72-96 h) - semi-chronic (2-3 weeks – Model Eco-System) - chronic (2-6 month - life-cycle)

32. Toxicology Toxic risk assessment: • Toxic identification • Determines if a chemical is toxic • Dose-response assessment • Strength of toxicity • Exposure assessment • How often humans are exposed to the chemical • Risk characterisation

33. Toxicology • NOAEL = non observable adverse effect level • LOAEL = lowest observable adverse effect level • Maximum daily uptake