Environmental Health &

Toxicology

Health & Disease

The common disease of sentient beings is to be diligent and earnest when catastrophe strikes but lax and remiss in normal times.

Master Ying KuangDisease= Abnormal change in the body’s condition that impairs important physical or physiological functions.

What defines healthy?

• people without friends have a 50% greater mortality rate than people with strong social networks.

Complete well being, not merely the absence of disease Well-being in which every individual realizes his or her own potential, can cope with the normal stresses of life, can work productively and fruitfully, and is able to make a contribution to her or his community.

Good physical health is when your body is functioning as it was designed to function.

1. Lifestyle. 2. Human Biology. 3. Environment. 4. Healthcare Services.

Who lacks morbidity? • Life expectancy at birth and infant mortality (10% of

score) • Causes of death: – Communicative and non-communicative diseases (40%

of score) • Death rates by three age groups: – less than 14, – 15-64 and – 65 and up (40% of score)

• Survival to 65 and life expectancy at 65 (10% of score) • http://images.businessweek.com/bloomberg/pdfs/W

ORLDS_HEALTHIEST_COUNTRIES.pdf

Top 5 Diseases 1990

Top 5 Diseases 2020

Pneumonia

Diarrhea

Perinatal

Depression

Heart disease

Heart Disease

Depression

Traffic accidents

Stroke

Chronic lung disease

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Estrogen mimics

• Attach to estrogen receptors in cells and mimic the action of the body's natural estrogen.

• Block the action of natural estrogen and are thus called estrogen antagonists.

• DDT and its metabolites may be responsible for a decrease in men's sperm counts since the 1940's, as well as for the increase in the number of cases of endometriosis

Ecological Diseases

• Chronic wasting disease– Prions– Transmissible Spongiform Encephalopathy

• Spread of disease– Contaminated feed

• Transmissible to humans?– Mad cow disease

Infectious & Emergent Diseases

• Many emerging diseases are caused by• Encroaching on pristine remote areas, • globalization • Mutations of pathogen• Ecosystem Services :regulating

Video: Infectious disease

Lyme disease AIDS

• An emerging disease is one that has appeared in a population for the first time, or that may have existed previously but is rapidly increasing in incidence or geographic range

Pesticide Resistance

• The protozoan parasite that causes malaria is now resistant to most antibiotics, while the mosquitoes that transmit it have developed resistance to many insecticides.– Natural selection and the ability of organisms to

evolve rapidly– Human tendencies to overuse pesticides speeds

up this process.

Antibiotic Resistance• At least half of the 100 million antibiotic doses

prescribed in the U.S. every year are unnecessary or are the wrong drug.

• Many people do not finish the full-course, creating resistant strains of bacteria.

ie. Antibiotic resistant strains of MRSA are spreading through hospitals in the US and China resulting in thousands of deaths.

• Antibiotics are routinely fed to U.S. farm animals to stimulate weight gain. These are excreted in urine and feces, and find their way into surface waters where they create more antibiotic resistance.

Antibiotic Resistance