Embalming Chemicals (Test 3) Flashcards
Material safety and data sheet.
- Tells you hazards of chemicals
MSDS
Amount that will kill 50% of the group to which it is administered.
LD50
Smallest dose that can kill a person.
Minimum lethal dose
The fixation of proteins. (Makes the proteins fixed and firmed).
Conveys the following properties:
- The viscosity is increase
- The tissue is firmer
- The resistance to enzymes is increased.
- Water solubility and sensitivity to hydrolysis is decreased.
Coagulation of proteins
The thickness of a liquid. The state of being thick, sticky and semifluid in consistency.
Viscosity
The movement of fluid from the point of injection to the tissues.
Distribution
Movement of fluid into the tissues.
Diffusion
- LD50
- Minimum lethal dose
- Action level
- Acute effect
- Hazardous chemical
- Health hazard
- PEL (permissible exposure level)
- STEL (Short term exposure limit)
- TWA (Time weighted average)
Information that the MSDS provides
Most of the chemicals involved with embalming are hazardous. This can tell you these hazards.
Importance of the MSDS to embalmers
- Aldehydes, alcohols, phenols, and formaldehyde “donor” compounds.
- Sanitize and preserve.`
- Preservatives
- Inactivate the proteins and amino acids.
- Inhibits further decomposition.
- Inactivates enzymes (proteins).
- Kills microorganisms.
- Destroys odors and eliminates further production (deodorants).
5 major functions of preservatives.
Cross linking the nitrogens:
- imide side chains
- Amino group
- Peptide bonds
- Inactivate the proteins and amino acids.
- Slow down decomposition, but they do not reverse it, nothing can.
- Inhibits further decomposition.
Inactivates enzymes from bacteria (putrefyers) and from your cells (autolytic).
- Inactivates enzymes (proteins)
Alter human tissue, renders the food source for saprophytic bacteria unusable.
- Kills microorganisms
- Alters amines that form from the hydrolysis, deamination, and decarboxylation of proteins during decay.
- The react with the nitrogens in the amines and neutralize them.
- Stop the decay of proteins which stops production of the amines.
- Destroys odors and eliminates further production.
Reacts with proteins to cause coagulation. Increases viscosity, the tissue becomes firmer, and the resistance to enzymes is increased, water soluibility and sensitivity to hydrolysis is decreased.
Formaldehyde
True or false-
Formaldehyde reacts with individual amino acids.
True - Formaldehyde can cross link proteins via the amino acids (the nitrogens).
Dehydration synthesis- Insertion of methalene group and removal of water in amino acids.
How formaldehyde cross links proteins.
- Colorless gas with irritating odor
- Soluble in water (how formalin is made)
- Combines with water to yield methylene glycol
- Polymerizes (paraformaldehyde)
- pH affects it
- basic :salt and methanol
- acidic: polymerizes
- It is neutralized by ammonia
- Cross links proteins
Properties of formaldehyde
Results in rigidity or firmness of tissue.
Cross-linking
Too much water in a system can prevent the proper cross-linking. This is due to the fact that it basically reverses the dehydration synthesis reaction that cross-links (adds the methylene bridges) between amino acids, causing them to break apart rather than come together.
Hydrolysis
The total amount of formaldehyde with which protein will combine to be completely preserved.
Formaldehyde demand
- Progression of decomposition
- Amount of amino acids
- Advanced decomposition
- Presence of urea
Factors that affect formaldehyde demand
More nitrogens are exposed and the formaldehyde demand increases.
Progression of decomposition
This means that there are more sites for formaldehyde to form a union with nitrogens.
More amino acids
These cases have a higher formaldehyde demand and a more concentrated arterial solution is required.
Advanced decomposition
The average body is 150lbs (65.4Kg) and contains about 10.7Kg or protein.
100g of solution requires 4.4g of formaldehyde preservation.
- How much formaldehyde do you need?
- Standard 30 index solution contains 30% formaldehyde
- 1oz = 29.8mL
- 16oz X 29.6mL = 473.6mL of 30 index
- 473.6mL X 0.3 = 142.08g of formaldehyde
- 80g of formaldehyde / 142.08g of formaldehyde =
- 31 bottles needed
If the concentration of formaldehyde is too high, it can seal the capillaries and prevent effective diffusion. Prevents good preservation and can cause the deeper musculature and tissue to go unfixed.
Walling off
- Causes rapid coagulation of blood - it must be thoroughly removed.
- Dehydrates tissues
- Constricts capillaries (issue when you want to inject other fluids after the arterial fluid)
- If pushed through too quickly, not enough formaldehyde will be present to effectively fix tissue (soft spots can form and decompose around fixed tissues).
Issues to consider when using formaldehyde
- Paraformaldehyde
- Trioxane
- Acetylaldehyde, pyruvic aldehyde
- Formaldehyde donors
Other aldehydes that can be used in addition to formaldehyde
A polymer of formaldehyde. Solid and can be used in hardening compounds, powered preparations etc.
Paraformaldehyde
A polymer of formaldehyde. Used in accessory fluids sometimes, but is very expensive and not as cost effective or arterial fluid.
Trioxane
In use in some more modern preparations of arterial fluids.
Other aldehydes: acetylaldehyde, pyruvic aldehyde
Liberate formaldehyde at slow rate (slow-release) low odor or “fumeless”.
- Slow and expensive, but more pleasant to the live people in the room.
Formaldehyde donors
Have two aldehyde groups (C=OH).
Dialdehydes
- Glyoxal
- Gluteraldehyde
Dialdehydes used in embalming
Yellowish in color- only used in cavity fluid.
Glyoxal
Cross links like formaldehyde, but it’s much larger and can’t penetrate tissue as well.
- Unlike formaldehyde, it is not restricted by pH
- Cold sterilant- much more effective at killing endospores than formaldehyde.
Gluteraldehyde
An alcohol that can be used as a preservative.
- excellent preservative and disinfectant
- penetrates into tissues, also bleaches
- stabilizes formaldehyde
- Can act as a vehicle for other compounds
- dehydrates
Methyl alcohol (methanol)
Boost the disinfectant qualities of preservatives, ingredients that function as preservatives also function as these.
- QAC
- Gluteraldehyde
- Phenol
- Disinfectants
- Good disinfectant
- Rapidly absorbed into the skin
- Can assist formaldehyde
- Does not produce firmness
- Bleaching agents
- OK- in cavity fluid, or to lighten discoloration on skin.
Phenol
- Germicidal (disinfecting) qualities
- Inhibit microorganisms as the method of preservation
- Primarily found in cavity fluids since it is not compatible with many dyes and wetting agents in arterial fluids.
Quaternary Ammonium Compounds
This is a dialdehyde.
Gluteraldehyde
This is a prototypical aromatic hydroxide.
- It has more acid characteristics than alcohol characteristics.
- The pH is about 6.
Phenol
These are salts of amines, all 4 hydrogens associated with ammonium are replaced with an alkyl group or an aromatic ring.
Quaternary Ammonium Compounds
Main purpose is to control the main preservative ingredient (usually formaldehyde).
- Control and slow the fixing of tissues with formaldehyde to permit diffusion through capillaries.
- Slow hardening to allow coloring agents to distribute evenly.
- Modifying agents
- Buffers
- Humectants
- Inorganic salts
Types of modifying agents
The body contains varying levels of acids and bases after death.
- Normal pH is slightly basic (in life)
- Immediately after death, pH is slightly acidic due to the breakdown of carbohydrates.
- Compartments of the body differ in pH so the injected fluids must be buffered.
- pH that is very basic will make formaldehyde decompose into a salt and methanol
- pH that is very acidic will polymerize formaldehyde into paraformaldehyde.
Importance of maintaining a stable pH in embalming
Considered modifying agents because they prevent wild fluctuations in pH when using formaldehyde. (They keep the formaldehyde from decomposing or polymerizing, helps maintain an even preservation).
Buffers
- Borax (sodium borate)
- Carbonates (sodium carbonate, magnesium carbonate)
Types of alkaline buffers
Helps formalin stay around the pH of 7.
- Stabilizes the formalin solutions increasing shelf life
- Reduces the graying effect of formaldehyde
- Can help keep formaldehyde stable for 2 years.
Borax (sodium borate)
Added with borate, it also helps keep the pH at around 7.
- not as effective as borates in extending the shelf life of formalin solutions.
Carbonates (sodium carbonate, magnesium carbonate)
Help retain moistures (most preservatives dehydrate)
- make tissue more pliable and rubbery
- also called “plasticizing agent” because of the pliability.
Humectants
- Glycerin
- Sorbitol
- Glycol
- Emulsified oils
- Gums
Types of humectants
Trihydroxyl Alcohol: good lubricator, solvent, hygroscopic, and if it stays in tissues it prevents over-drying.
Glycerin
Polyhydroxyl Alcohol: lose water more slowly than glycerine and controls moisture loss better.
- more commonly used than glycerin, but at low temperatures, drop out of the solution.
Sorbitol
Dihydroxyl Alcohol: Has similar characteristics to sorbitol
- ethylene glycol
- propylene glycol
Glycol
Moisture retaining and softening material.
Ethylene glycol
Better than glycerin at inhibiting mold.
Propylene glycol
Lanolin, and other oils are held in emulsions to help stabilize them and to help them remain uniform over a long period.
Emulsified oils
When added to water, well and retain moisture. Large size keeps them in the capillary bed where they can restore moisture to the area. (This is good if the viewing is delayed).
- vegetable - cellulose (karaya, tragacanth)
- Synthetic: cellulose like, man made.
Gums
React with ionized calcium preventing blood from clotting.-
- Work 2 ways:
1. Softens water
2. Works directly in the blood
- Anticoagulants
Either combine with Ca= or tie it up to prevent clotting.
Action of anticoagulants