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Flashcards in water toxicants Deck (30)
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1

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

ingredient
food processing
irrigation
livestock drinking water
aquaculture
post harvest activities

2

Water may lead to what types of contaminants?

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

3

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

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

4

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

volatile organic compounds
in ground/surface water in urban area

5

PAHs are: _____. How are they produced?

polyaromatic hydrocarbons
incomplete combustion of organic material

6

examples of radioactive elements contaminating water:

Iodine 131, Cesium 137, Barium 140

7

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

arsenic
contaminated irrigation water

8

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

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

9

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

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

10

What is a common source of nitrates in water?

fertilizer runoff, septic leaching

11

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

no, varies with time
depends on rainfall, season, changes in land, human activity, etc

12

What could cause an increase in PAHs in seafood?

pollution; oil spill

13

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

FALSE: higher concentration due to BIOACCUMULATION

14

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

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

15

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

location it was grown/caught
species
size

16

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

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

wastes in water can be fertilizer, has nutrients

17

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

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

18

Where can water be sourced from? (4)

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

19

Should the use of wastewater in agriculture be banned?

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

20

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

affect food processing
affect sensory qualities

21

____ water is safe, drinkable water.

potable

22

food production/processing must use ____ water.

potable

23

The CFIA guidelines for food industries: (3)

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

24

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

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?

25

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

higher quality

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.

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

27

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

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

28

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

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

29

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

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

30

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

increasing (faster than population growth!)
HPV (high production volume) chemicals