Environmental hazards

Question 1

Burden 
Acute 
Chronic 
Health effects 
Routes of exposure 

Of chemical hazards

Answer 1

• 47000 deaths / year due to direct poisoning
• acute toxicity
• long term leads to morbidity and mortality
• cancer , damage to CNS and immune system , impairment of reproductive functioning and growth
• air , soil , food and water

Question 2

Source
Burden
Effects

Of lead

Answer 2

• water pipe , paint , cosmetics , food cans , gasoline
• 1 in 3 children in LIC affected by lead
• acute is encephalitis
• chronic is anaemia , reduced IQ, violent behavior , learning disabilities

Question 3

Source
Effects

Of pesticides

Answer 3

• common in Malawi is organophosphates
• acute is acute toxicity
• chronic is neurological, developmental, reproductive , cancer , sterility , cognitive effects , spontaneous abortions

Question 4

Effects of the following

Vinyl chloride
Asbestos
Mercury
Benzene

Answer 4

• hepatic angiosarcoma
• malignant mesothelioma , asbestosis
• Minamata disease
• leukemia

Question 5

Burden of indoor pollution

Answer 5

• 3rd important risk factor ( behind malnutrition and unsafe sex ) of disease in high mortality developing countries
• 1.6 million annual deaths
• 15% of all lung cancers
• 25% of all COPD ( chronic obstructory pulmonary disease )
• 59% death in females
• 56% death in kids under 5

Question 6

Effects of indoor pollution

Answer 6

• cancer
• pneumonia
• chronic respiratory diseases
• death

Question 7

Burden of outdoor pollution

Effects of both indoor and outdoor pollutants

Answer 7

• 0.5% total disease burden
• 1.5% deaths
• 5% lung cancer
• 2% of all CVD cause
• eye irritation
• death
• cancer
• reduced O2 carrying capacity of blood
• pulmonary and respiratory system damage

Question 8

Source
Effects ( including prenatal exposure )

Of ionizing radiation

Answer 8

• natural ( radon , environment ie background radiation ) or synthetic ( medical ie X-ray or chemotherapy and radioactive waste )
• acute is hair loss , skin redness , radiation burns and acute radiation syndrome
• chronic is cancer
• prenata exposure in early pregnancies associated with brain damage

Question 9

Source
Effects

Of non ionizing radiation

Answer 9

• phone, tv , radio , microwave etc and ultraviolet exposure
• UV effects are melanoma and non melanoma skin cancers and cataracts ( clouding of lens )
• increased leukemia risk with high voltage lines

Question 10

Define biohazard

Answer 10

• infections agents and their by products or biologically active materials that present a risk ( potential risk ) to humans directly or indirectly by damaging the environment
• can be recombinant DNA , micro organisms or biologically active agents

Question 11

Use of dose response graph

Describe the graphs three stages

Define threshold

Answer 11

• to measure effect of exposure of hazard on an organism
• sub threshold ( low exposure and no effect )
• linear level ( increase in response proportional to increase in dose )
• lowest dose at which an overt ( particular ) effect is seen in organisms

Question 12

Define latent and incubation period

Define synergism

Answer 12

• time from exposure to infectiousness
• time from exposure to overt signs and symptoms
• combined effect of several exposures which are greater than the sum of their parts

Question 13

Routes of biohazard entry

Effects of biohazards

Answer 13

• GIT
• respiratory
• contact contaminated object
• contact bodily fluids of infected person
• infection
• allergy
• poisoning
• death

Question 14

Hepatitis B and HIV prevalence ( and cause )in health workers and mitigation’s

Answer 14

• 35% of all hep B and 10% HIV cases among health workers due to occupational exposure
• both 95% preventable with immunization ( hepatitis b ) and HIV through low cost measures

Question 15

Prevention and control of biohazards

Answer 15

• personal hygiene good
• disinfect and sterilize
• proper waste management
• eliminate source of contamination
• immunize