Collection,Dispatch & Processing of toxicological samples. Dr Faheem Sultan Division of Veterinary Pharmacology & Toxicology Indian Veterinary Research Institute

3. The
practitioner
and
diagnostic
laboratory staff must maintain good
communication in order to complete
their diagnostic efforts efficiently and
provide optimal service to the client.
The laboratory staff can provide guidance
when there are questions regarding
sample collection and handling, as well
as offering assistance in interpretation of
test results.

4. 
A detailed case history, owner, species, breed, sex, age,
animal identification, clinical signs, gross appearance
(including size and location) of the lesion(s), previous
treatment (if any), time of recurrence from any previous
treatment, and morbidity/mortality in the group.

The submission form should be placed in a waterproof bag.

Waterproof markers should be used when labelling .

5. If a known toxin is suspected, a specific
analysis should always be requested.
 A complete description of clinical and
epidemiologic findings.
 Tissues or fluids for chemical analysis
should be as fresh as possible and kept
refrigerated.
 In rare instances a chemical preservative
is required.


6. 






Samples can be preserved for 72 hr if packed
in a Styrofoam box with dry ice.
Plastic containers, both bags and jars, are
ideal.
Jars with metal screw caps should be
avoided.
Packed individually & well labelled.
Must conform to postal regulations.
If feed or water is suspected as the source of
poisoning, it should accompany the tissue
samples.
In some instances, suspected feed may be
fed to experimental animals .

8. Peripheral blood concentration has
been shown to be more reliable.
 Usually 20 ml of blood is sufficient and it
has to be preserved in sodium fluoride of
10mg/ml and potassium oxalate, 30
mg/10 ml of blood concentration.


The glass container should be made of
amber glass.

9. 
Sodium fluoride protects blood from
postmortem changes such as bacterial
production of ethanol or other alcohols.

It also helps to protect other labile drugs
such as cocaine, ntrazepam and
clonazepam from degradation.

K2EDTA may also prove useful in cases
of suspected fluoride poisoning.

10. 
Concentrations are generally higher than in
blood.

A number of metabolites may also be
present.


Preserved in sodium fluoride.
A sample of 20 ml is sufficient for
toxicological analysis.

11. 

Opiates and acetaminophen(
paracetamol).
It is not routinely preserved.

12. Useful for alcohols, or in diabetes and
insulin related deaths.
 Useful where the body has
decomposed.
 Biochemical tests such as urea, creatine,
glucose, lactose and alcohol.
 Is preserved with sodium fluoride (10
mg/ml)


13. 
Rarely required for toxicological analysis.

The CSF sample has to be preserved in
sodium fluoride.

14. 
Like PERICARDIAL and SYNOVIAL FLUIDS
can be used for toxicological analysis
like alcohol.

16. The most important tissue because it
concentrates many substances.
 Establish whether acute or chronic
toxicity.
 A minimum of 100 gm is sufficient for
toxicological analysis.


17. 
Rumen, stomach and small intestine with
their contents.

For toxins taken orally as the
concentrations will be many times higher
than in other fluids.

18. Analysing chronic poison ( heavy metals)
or drug of abuse (opioids).
 Distinguish between episodic or
continuous exposure.
 For those poisons which may have
already been eliminated from the body
by the time of death.
 About 500 ug (20 – 30 hairs ) & the whole
nail.


19. 
In decomposed body, if maggots are
present 20 gms of maggots .

Saturated common salt as the
preservative.

It only provides qualitative information.

20. 
The injection site has to be preserved.
The skin sample with the underneath
muscle tissue around the injection site
area must be preserved along with a
control sample .
 Preserve in saturated solution of
common salt.


21. SUSPECTED POISON
SAMPLE COLLECTION
REMARKS
Ammonia
Whole blood ,Plasma
Urine,Rumen contents
Frozen
Frozen/1-2 dps HgCl2
Anticoagulants (warfarin
and related compounds)
Whole blood
Liver
Feed
Stomach contents
Heparin or EDTA
Refrigerated
Arsenic
Liver
Kidney
Urine
Ingesta
Feed
Chlorates
Stomach contents
Urine
Feed
Frozen, in airtight
container
Chlorinated
hydrocarbons
Cerebrum
Ingesta
Body fat
Liver Kidney
Kidney
Use only glass containers
Avoid contamination
Refrigerated or frozen

22. SUSPECTED POISON
SAMPLE
REMARKS
Copper (and Ni, Fe, Co,
Cr, and Tl)
Kidney
Liver
Serum
Feed, Feces
Whole blood
Cholinesterase
Serum
Cerebellum, CSF
Frozen
Cyanide
Forage
Whole Blood
Liver
Rush to laboratory or ship
promptly, frozen in
airtight container
Dicoumarol
Forage
Liver

23. SUSPECTED POISON
SAMPLE COLLECTION
SAMPLE COLLECTION
Ethylene Glycol
Serum, Urine, Kidneys
Fresh plus formalin fixed
Flourides
Bone, Water
Forage, Urine
Bones are the best.
Herbicides
Treated weeds, Urine
Ingesta, Liver or kidney
Ionophores
Feed, Rumen contents
Heart, Skeletal muscle
Lead (also Hg, Mo, Ni,
and Tl)
Kidney, Whole blood
Liver, Urine
Heparinized blood
preferred
Mercury and
molybdenum
Kidney, Whole blood
Liver, Feed
Heparinized blood
Mycotoxins
Grain, forages
Liver, kidney
Specific tests

24. SUSPECTED POISON
SAMPLE
REMARKS
Nitrate
Forage,H2O,Bodyflds(e.g. Refrigerated
,aqueous humor)
Organophosphates (and
carbamates)
Feed, Ingesta
Urine
Also send urine, blood,
and stomach contents
from normal animals.
Phenols
Gastric or rumen
contents
In air tight container.
Polychlorinated(polybro
minated)biphenyls
Fat,Cerebrum
Feed
Rumen pH
Ingesta
Frozen
Selenium
Whole blood, Feed
Liver, Hair clippings
Heparinized
Sodium (NaCl)
Brain, Serum
CSF, Feed
Other half fixed in
formalin

25. SUSPECTED POISON
SAMPLE
REMARK
Sodium fluoroacetate
(1080)
Stomach contents
Liver
Frozen
Strychnine (and some
Liver
other convulsants such as Kidney
bromethalin)
Stomach contents
Sulfates
Water, Brain
Fixed in formalin
Vitamin A (also D and E)
Liver, Serum
Frozen
Urea
Feed
Vitamin D 3 (rodenticides) Kidney
Zinc Phosphide
Liver, Gastric contents
Frozen
Zinc
Use trace mineral tubes
Liver, Kidney
Serum

26. 
The ideal samples are best sent in their original state without
adding any preservative in a refrigerated storage (4C) within
few hours.

For long term storage it has to be kept in freezer
analysed and disposed off.

The most commonly used preservative for visceral tissues are
saturated solution of common salt.

The other option is rectified spirit (90% ethanol) except in
cases of poisoning due to alcohol, chloral hydrate,
chloroform, phenol formaldehyde, ether, and phosphorus.
(-10C) until

27. 
Properly sealed and labelled.

Avoid loss during transport.

Comply with health and safety regulations.


The use of tamper-evident seals.
Should be handed over to the investigating
officer after obtaining proper receipt.

28. 
The choice of method for testing is highly
dependent on:
1) Kind of substance one expects.
2) The material on which the testing is
performed.

29. PROCESS/TEST
SUBSTRATE
GAS-LIQUID CHROMATOGRAPHY
VOLATILE ORGANIC COMPOUNDS.
DESTRUCTION OF THE ORGANIC MATRIX DETECTION OF METALS
BY CHEMICAL OR THERMAL OXIDATION.
THE REINSCH TEST,
EMISSION SPECTROSCOPY OR X-RAY
DIFFRACTION.
DETECTION OF METALS
THIN-LAYER CHROMATOGRAPHY, GASLIQUID CHROMATOGRAPHY AND
IMMUNOASSAY.
PESTICIDES, NATURAL
PRODUCTS, POLLUTANTS AND
INDUSTRIAL COMPOUNDS
OLDER METHODS INCLUDE: SPOT TEST
THE MARQUIS REAGENT, MECKE
REAGENT, AND FROEHDE'S REAGENT
FOR OPIATES
MARQUIS REAGENT AND SIMON'S
REAGENT
AMPHETAMINE, METHAMPHETAMINE &
OTHER ANALOGS
THE SCOTT'S TEST
DUQUENOIS REAGENT
FOR COCAINE
MARIJUANA AND
OTHER CANNABINOIDS