Adverse effects of some chemicals

Question 1

What are dissolved organic compounds?

Answer 1

They are organic compounds dissolved in water that are non-toxic but contribute to BOD and COD.

Question 2

Examples of dissolved organic compounds. How do they effect the BOD and COD?

Answer 2

Sugars, amino acids, proteins, carbohydrates, lipids. They will be decomposed by bacteria. increasing oxygen demand and reducing the dissolved oxygen level.

Question 3

Source of Arsenic to water.

Answer 3

Fungicides, industrial waste water, ground water, waste of phosphate fertilisers.

Question 4

Effects of arsenic (2)

Answer 4

carcinogen. can cause arsenicosis.

Question 5

Source of Cadmium to water.

Answer 5

Mining waste. rechargeable batteries and metal refining and industrial emission

Question 6

Effects of Cd (3)

Answer 6

Enzyme deactivation, high blood pressure and kidney damage.

Question 7

Lead sources to water

Answer 7

industrial emissions, mining waste, leaded paints and leaded gasoline.

Question 8

Effects of lead. (3)

Answer 8

Anemia, mental retardation of children, kidney and reproductive dysfunction

Question 9

Mercury = Hg, or Hg2+ sources to water.

Answer 9

Industrial waste, in equipment containing mercury like CFL bulbs and thermometers. coal burning. traces are present in minerals

Question 10

Mercury effects (4)

Answer 10

Minamata disease, brain and kidney damage, insomnia.

Question 11

examples for toxic or non hazardous organic compounds

Answer 11

Aldrin, Furan, DDT.

Question 12

Examples for toxic water disinfection by products. how are they produced?

Answer 12

monochloroamine. chloroform. bromoform. produced by reaction of hypochlorite ions and dissolved organic substances. hypochlorite ions produced by Cl2 or hypochlorite salts used for water disinfection.

Question 13

Reason for using additives.

Answer 13

minimise cost of production.
facilitate production.
consumer attraction
to impose mechanical and workable properties to the polymer.

Question 14

Pthalate uses and effects.

Answer 14

To make plastics less rigid and more flexible. can lead to decrease in hormone secretion by endocrine system, and is a carcinogen.

Question 15

Leaded pigments use and effect

Answer 15

To produce vivid colors in plastics. kidney damage, slow mental growth in children, central nervous system damage. decrease hormone secretion

Question 16

brominated flame retardants uses and effects

Answer 16

used as a flame retardant. decrease hormone secretion

Question 17

bisphenol A effects (BPA)

Answer 17

reduce hormone secretion. mimics estrogen and disturbs its function. organ development issues in small children.