toxic metals

Question 1

three ways to classify metals

Answer 1

major toxic metals, essential metals, metals and medicine

Question 2

three ways to classify metals: major toxic metals

Answer 2

Not necessary to sustain life
Toxic at both acute and chronic exposure levels
Arsenic (semimetal), beryllium, cadmium, chromium, lead, mercury, nickel

Question 3

three ways to classify metals: essential metals

Answer 3

Essential for life at trace amounts, but have the potential for toxicity at high concentrations
Iron, copper, magnesium, zinc

Question 4

three ways to classify metals: metals and medicine

Answer 4

Metals used for medical therapy

Aluminum, lithium, platinum

Question 5

five main routs of exposure to heavy metals

Answer 5

air, soil, dust, water, biota

Question 6

Arsenic (As)

Answer 6

What is it: Crystalline metalloid

How are we exposed: Naturally occurs
Once used for medical purposes
industrial/commercial sources

How common is exposure?: ubiquitous in soil and water
2001 EPA standard for As in drinking water

How does it affect us: Acutely poisonous, varies in toxicity depending on chemical form
Risk factor for cancer
Melanosis
Adverse pregnancy outcomes

Question 7

Beryllium

Answer 7

What is it: light, yet strong metal, commonly used for industrial purposes

How are we exposed: inhalation

How common is exposure?: highest levels in occupational settings
Coal burning emissions

How does it affect us: Berylliosis → chronic beryllium disease (CBD)
Influenced by genetic susceptibility
Carcinogenic

Question 8

Cadmium

Answer 8

What is it: found in soils, rocks and coal

How are we exposed:
Dietary intake → bioaccumulation in shellfish and plants
Occupation (mining and battery production)

How common is exposure?: highest levels in occupational settings but common exposure through cigarettes and diet

How does it affect us:
High blood pressure → cardiovascular disease
Kidney damage
Itai-itai disease

Question 9

Chromium

Answer 9

What is it: naturally occurs in soils and volcanic minerals
Various forms (essential and toxic)

How are we exposed:
Occupational → inhalation
General → dietary

How common is exposure?: contaminated food and water

How does it affect us:
Carcinogen, organ damage, digestive issues, skin ulcers and respiratory problems

Question 10

mercury

Answer 10

What is it: naturally occurring, exists in three forms (quicksilver)

How are we exposed:
Once used as a medicine
Ingestion: dental amalgams, diet bioaccumulation
Inhalation: occupational (cinnabar processing)

How common is exposure?: depends on diet

How does it affect us:
Fetal and child brain development
Neurologic outcomes → minamata disease

Question 11

Nickel

Answer 11

What is it: found in earth’s crust

How are we exposed: through low levels from industrial products
Occupational: inhalation and dermal

How common is exposure?: universal and unavoidable

How does it affect us:
Skin allergy
Cardiovascular disease
Fibrosis of the lungs → respiratory cancers

Question 12

example of ways heavy metals are in the air

Answer 12

Mainly occupational

Smelting, mining

Question 13

example of ways heavy metals are in the soil

Answer 13

mining/smelting
Ingestion: mainly toddlers and babies
Lead → paint chips

Question 14

example of ways heavy metals are in the dust

Answer 14

mining/smelting
Ingestion: mainly toddlers and babies
Lead → paint chips

Question 15

example of ways heavy metals are in the water

Answer 15

Naturally occurs
Well water vs. public water
Arsenic / mercury 
Rust from pipes (iron)
Old pipes (lead)

Question 16

example of ways heavy metals are in the biota

Answer 16

biomagnification/bioaccumulation
(mercury in fish)
Organotin pesticides
(End up in water → fish)
Leaded glaze and glass
(Paprika and wheat)

Question 17

Biomagnification/bioaccumulation

Answer 17

The gradual buildup of substances, such as pesticides, or other chemicals in an organism