water toxicants

Question 1

What are the main uses of water in relation to food? (6)

Answer 1

ingredient
food processing
irrigation
livestock drinking water
aquaculture
post harvest activities

Question 2

Water may lead to what types of contaminants?

Answer 2

organic (pesticides, PAHs, Volatile organic compounds)
inorganic (trace metals, nitrates, radioactive compounds)
biological hazards (pathogens, toxins)

Question 3

common trace metals found in ground and surface water: (7)

Answer 3

Pb, Cu, Cr, As, Hg, Cd, Zn

Question 4

What are VOCs? Where are they commonly found in water?

Answer 4

volatile organic compounds

in ground/surface water in urban area

Question 5

PAHs are: _____. How are they produced?

Answer 5

polyaromatic hydrocarbons

incomplete combustion of organic material

Question 6

examples of radioactive elements contaminating water:

Answer 6

Iodine 131, Cesium 137, Barium 140

Question 7

Rice has been noted to have high levels of _____, due to _____.

Answer 7

arsenic

contaminated irrigation water

Question 8

How does contaminated water affect agriculture in the food supply chain?

Answer 8

irrigation: may introduce chemical contaminants and pathogens from wastewater
animals: contaminants may accumulate; be present in meat and other products
aquaculture: accumulate in fish

Question 9

What is the source of many inorganic contaminants? (6)

Answer 9

natural deposits
discharge from metal refineries
wastewater from factories/plants
mining
pipe corrosion
fertilizer runoff

Question 10

What is a common source of nitrates in water?

Answer 10

fertilizer runoff, septic leaching

Question 11

Do contaminant levels stay constant in water? Why or why not?

Answer 11

no, varies with time

depends on rainfall, season, changes in land, human activity, etc

Question 12

What could cause an increase in PAHs in seafood?

Answer 12

pollution; oil spill

Question 13

True/False: a larger fish will have lower concentration of contaminants in its meat, because it is evenly distributed throughout

Answer 13

FALSE: higher concentration due to BIOACCUMULATION

Question 14

consumption of _____ fish should be limited, especially for ____. Why?

Answer 14

large, carnivorous
pregnant women, children
higher levels of toxicants such as mercury, PAHs, etc

Question 15

The levels of contaminants present in the fish will depend on:

Answer 15

location it was grown/caught
species
size

Question 16

Why would wastewater be commonly used as an irrigation source despite risks? (2)

Answer 16

Used in rural areas; other sources are not available (poorer areas, developing countries)

wastes in water can be fertilizer, has nutrients

Question 17

How can wastewater be safely reused? How can this be done? (3)

Answer 17

INDIRECT reuse; need intermediate step
(some disinfection, filtration, treatment)

use as water for growing feed (pasture, aquatic plants)
refill aquifers (groundwater supply)
use for irrigation, but not in contact with edible portions
*keep away from potable water supplies

Question 18

Where can water be sourced from? (4)

Answer 18

private supply (rainwater, groundwater, surface water)
public supply

Question 19

Should the use of wastewater in agriculture be banned?

Answer 19

No; impact livelihood of many farmers with no other choice; wasting nutrients in wastewater1

Question 20

In what ways does water quality influence food, in addition to safety?

Answer 20

affect food processing

affect sensory qualities

Question 21

____ water is safe, drinkable water.

Answer 21

potable

Question 22

food production/processing must use ____ water.

Answer 22

potable

Question 23

The CFIA guidelines for food industries: (3)

Answer 23

1. meet water safety req for handling, production, processing of food (*and have action plan if water become unsafe - boil water alert)
2. establish communication with municipal/provincial authorities to stay informed about safety status of water
3. the industry is responsible for producing safe food! CFIA will inspect and enforce

Question 24

What criteria need to be checked to see if the water is suitable to use? (4)

Answer 24

1. Does it contain biological or chemical hazards in significant amounts?
2. is it to be consumed, or contact consumables?
3. Is it going to be treated to eliminate hazards before contact/consumption?
4. is the final product going to be treated to eliminate hazards before consumption?

Question 25

The further down the food supply chain, the ____ the water needs to be

Answer 25

higher quality

Question 26

True/False: if there is contamination in a food due to unsafe water in production, this is the fault of the public water system and not the industry.

Answer 26

False; responsibility of the industry to check their water source and make sure food is safe

Question 27

How do the quantities and qualities of water for agriculture and food processing compare?

Answer 27

agriculture (fish, animal, plants): high quantity, lower quality
food: low quantity, potable quality

Question 28

What is a special exception in agriculture for water quality? Why?

Answer 28

sprouts

direct contact with edible portion; usually not thoroughly cleaned or cooked

Question 29

Should water be included in risk management plans? What is necessary? (3)

Answer 29

YES: include as ingredient in HACCP plans

• describe the cycle of water through plant (sources, pipes, reuse), + INTENDED USE
• review water safety reports from suppliers, test to validate
• crisis management for when water quality is off the limits

Question 30

currently, use of chemicals is rapidly (increasing/decreasing). The most widely present are known as ____.

Answer 30

increasing (faster than population growth!)

HPV (high production volume) chemicals