Pentachlorophenol (PCP) Flashcards Preview

Toxicology Fall17 > Pentachlorophenol (PCP) > Flashcards

Flashcards in Pentachlorophenol (PCP) Deck (24)
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1
Q

What are PCPs used for?

A

wood preservatives - protection from fungal rot and insects

2
Q

How are animals exposed to PCPs?

A

licking treated wood, inhalation of toxic amounts from treated walls in sheds or barns
Vapors can also penetrate the skin
Ingestion of contaminated feeds or water

3
Q

Are PCPs water soluble?

A

not very much - but they are soluble in oils and organic solvents

**the SALT forms are soluble in water

4
Q

What temperatures promote increased vapors from PCPs?

A

high ambient temp - can increase the concentration of toxic vapors

5
Q

What do older PCP preparations include that is a carcinogenic and teratogenic?

A

Dioxins

6
Q

What is the acute oral or dermal LD50 of PCPs for domestic animals? What category of toxicity do they belong to?

A

ranges from 100 - 200mg/kg

Moderately toxic

**Chronic toxicity ranges from 40-70 mg/kg

7
Q

What factors will increase the toxicity of PCPs?

A

High ambient temperature, oily or organic solvent vehicles, previous exposure, poor condition of animal, newborn, hyperthyroidsim (increased metabolism =increased body temp)

8
Q

Where can/do PCPs get stored in the body?

A

Adipose tissue

***lipophilic

9
Q

What factors will decrease the toxicity of PCPs?

A

Cold temp, antithyroid drugs, and the presence of body fat (since it will go to the fat for storage - where it is inactive)

10
Q

How are PCPs absorbed?

A

Lipophilic = readily absorbed from the GIT, inhalation, thru intact skin

11
Q

Where are PCPs distributed throughout the body

A

All over - with some accumulation in fat

12
Q

What is the average half life of PCPs in the body?

A

a day and a half to two days

13
Q

How are PCPs metabolized and excreted?

A

Conjucation to glucuronic acid –> Glucuronides are excreted in the urine

Cats are deficient

14
Q

Residues of PCPs in tissues and fat are depleted from the body within ____ days of exposure

A

7 days / 1 week

15
Q

What is the MOA of PCPs?

A

irritant to resp. tract, mm, and skin

uncouples oxidated phosphorylation and blocks or decreased ATP –> lack of energy = increased oxygen demand in efforts to produce ATP –>

  • overheating
  • metabolic acidosis
  • dehydration

decreased cellular energy = neuro toxic, wt loss, decreased milk production, repro problems

16
Q

What clinical signs are associated with acute PCP toxicosis?

A

“animal cooks in it’s own heat”

fever, tachycardia, dyspnea, cyanosis, sz, collapse, death

***newborn pigs = hyperthermia, skin irritation, rapid death

17
Q

What clinical signs are associated with chronic PCP toxicosis?

A

Wt. loss, decreased milk production, anemia, fetal malformations/abortions

Fever and resp. distress may be ABSENT

18
Q

T/F: PCP toxicosis will increase the onset of rigor mortis

A

TRUE

hyperthermia will increase the onset of rigormortis and that is one of the main clinical signs

19
Q

What lesions will be noted with PCP toxicosis?

A

Fast onset of rigor mortis
local irritation to MM and skin
degenerative lesions in the liver and kidney
Dark blood = oxygen deprived
Hyperkeratosis of the skin and villous like hyperplasia of urinary bladder in chronic cases (this is pathopneumonic but RARELY seen)

20
Q

What samples can be used for PCP chemical analysis?

A

blood and urine from a live animal

kidney and skin of a dead animal

21
Q

How is a PCP toxicosis diagnosis made?

A

History of exposure + signs of rapid overheating and respiratory distress, rapid rigor mortis, dark blood, and chemical analysis

22
Q

What are ddx for PCP poisoning?

A

Heat stroke (differentiated via hx)

Toxicants causing resp distress:
Nitrate (should have brown blood + no fever)
CO (bright red blood + no fever)
Pesticides (Neuromuscular signs/autonomic signs)
Peracute infections

23
Q

What is the course of tx for PCP poisoning?

A

General and symptomatic

emetics or G.L. with sodium bicarb
ACTIVATED CHARCOAL or mineral oil
Soap/water detox bath

O2 therapy, IVF, decrease body temp, prophylactic ABs

24
Q

What is the prognosis for animals with PCP toxicosis?

A

If the animal survives the first 24 hours - chances for a complete recovery are fair