SGCEP SCIE 1121 Environmental Science Spring 2012 Section Steve Thompson:

Transcription

1 SGCEP SCIE 1121 Environmental Science Spring 2012 Section Steve Thompson: 1

2 OK this book has done it again... They have crammed WAY too much information in this chapter. It goes all over the place, ranging from bird flu, through environmental health as it relates to outdoor pollution, to public health, to cultural versus biological versus physical versus chemical hazards, to poor versus wealthy risk factors, and then onto tobacco use, and then infectious disease, and then indoor pollutants and allergens, onto building your home in disasterprone areas, and ending up with risk assessment. You ve got to be kidding! 2

3 Therefore, I ll do as I ve done a few times before... And just discuss a few of the key slides from their suggested presentation, and then we ll all watch a pretty good video that illustrates at least some of the points they are trying to get across in the chapter. Here that documentary is from the Public Broadcasting Service (PBS) and is a part of their series Rx for Survival ( wgbh/rxforsurvival/). The one we ll watch is Deadly Messengers. 3

4 Categories of pollution 4 Pollution: the presence of a substance in the environment that because of its composition or quantity prevents functioning of natural processes and produces undesirable environmental or health effects. This can be a lot of different things! Here s some major ones. Don t worry about the details, but do understand the concepts.

5 Indoor air pollution... Can be particularly sneaky. It can be all around us without us even knowing it. Asthma, other allergy problems, and even sickbuilding syndrome can result, if levels rise too high. 5

6 A big chunk of the chapter is on... Infectious diseases. We ll look at those carried by mosquito vectors in the documentary. Here let s check out the prevalence of a few, mosquito carried and otherwise, worldwide: Avian (H5N1) influenza; Tuberculosis; and... Malaria. 6

7 Countries with avian flu, 2008 The concerns here are two-fold. When viruses cross species borders, they are typically much more virulent; plus they can often hybridize with viruses from the new host producing new, previously unseen strains. 7

8 Global map of tuberculosis Almost a third of the world s population is infected with the bacterium that causes TB. It is number four in the list of infectious disease killers. And, tragically, many strains are rapidly evolving multiple antibiotic resistance! See: evolution/library/11/2/e_s_6.html 8

9 Malaria incidence per 1,000 population, 2006 Almost a million deaths/year worldwide are attributed to malaria, number five in the list, caused by the protist Plasmodium, it is one of the many mosquito vector borne infectious diseases. See e.g. 9

10 Life cycle of malarial parasite 10 Its life cycle is particularly complicated. And most of the time the parasite spends in the liver and in red blood cells it is hidden from the host immune system!

11 The remaining slides we ll check out have to do with... General human health risk factors and mortalities. For this entire area, including infectious disease, be sure to check out: The World Health Organization, ; Environment and Human Health, Inc., ; The Environmental Protection Agency, and... The Centers for Disease Control and Prevention, 11

12 U.S.A. deaths from cultural hazards Your text describes cultural hazards as risk factors associated with personal choice and lifestyle. 40% of deaths in the U.S.A. are a result of these sort of factors! As is obvious here, smoking is number one, followed closely by overeating/under exercising. 12

13 U.S.A. deaths caused by smoking Almost 30% of all cancer deaths in the U.S.A.! Of those almost half a million deaths from tobacco a year in the U.S.A., here s how the people are killed by it. Notice a significant portion aren t even doing the smoking themselves! 13

14 The 10 leading global risk factors These ten factors are responsible for more than one third of all deaths globally! A DALY is a disability-adjusted life year, i.e. about one healthy life year. Notice the discrepancy between wealthy and poor nations. 14

15 Loss of life expectancy from various risks Here s the loss of life expectancy associated with various risk factors in a typical developed country. Notice that ranked this way, excessively drinking alcohol to the point of being an alcoholic is the number one risk factor in wealthier nations. What doesn t make sense to me is why the smoking category is for men only. 15

16 OK, that s enough... On to the documentary. Again, this is Deadly Messengers from the PBS series Rx for Survival url= aid=8716&xtid=44352 It s 56 minutes long. And next time we ll talk about human induced global climate change (i.e. global warming). 16