Industry Related Toxicants Flashcards
Types of petroleum products?
crude oil–sweet crude oil and sour crude oil; refined petroleum products–aliphatic and aromatic hydrocarbons
Properties of sweet crude oil?
rich in low temp distillates–such as gasoline, kerosene and naphtha
Properties of sour crude oil?
contains high sulfur, but less low temp distillates–such as lubricating oil and gas oil
Name the different categories of refined petroleum products.
Short chain aliphatics (5 carbons), chlorinated aliphatic hydrocarbons
Uses of petroleum products?
fuels–propane, gasoline, kerosene, diesel oil; solvents–paint thinners, engine degreaser, carriers for insecticides, paints and medications; lubricant–motor oil, waxes, asphalt
Source of petroleum product toxicosis?
petroleum distillates–ie gas, kerosene, lubricating oils, fuel oils, diesel oil (farms/houses); crude petroleum (drilling operations); oil spills during transport; open containers of oil, kerosene, gas (cattle)
Properties of petroleum products?
highly irritant to MM, oily, many contain toxic materials, some oils contain chlorinated naphthalenes (very stable)
Chlorinated naphthalenes can cause ________.
bovine skin hyperkeratosis–thickening of the stratrum corneum (the outermost layer of the epidermis)
T/F Sour crude is more toxic than sweet crude.
FALSE! Sweet crude is more toxic than sour crude.
What species are the most susceptible to petroleum product toxicosis?
cattle–but horses, cats, dogs are also susceptible
T/F Long chain aliphatics cause aspiration pneumonia.
TRUE
T/F Short chain aliphatics have high toxicity and are very volatile.
FALSE–they are very volatile but they have a low toxicity
Examples of short chain aliphatics?
Methane, ethane, propane, and butane
Examples of long chain aliphatics?
Gasoline, kerosine, petroleum distillates (vehicles for insecticides), mineral seal oil, and Stoddard solvent
Examples of chlorinated aliphatic hydrocarbons?
carbon tetrachloride, chloroform, tetrachloroethane, trichloroethane, trichloroethylene, and tetrachloroethylene (found in dry cleaning and degreasing solvents)
note:toxicity listed in descending order
Examples of aromatic hydrocarbons?
benzene, toluene, xylene–Used in quick-drying paints, resins, glues, and plastics
_______ at 60 ppm in air following prolonged exposure can cause bone marrow suppression.
aromatic hydrocarbons
What animals are most frequently poisoned with refined petroleum products?
small animals
What animals are highly susceptible to oil spills?
aquatic wildlife and birds
Physicochemical properties of petroleum products?
- products with high boiling points such as asphalt, mineral oil or waxes are relatively non-toxic because of poor absorption
- more volatile compounds are generally more toxic because of more absorption
- products of low boiling points, low viscosity and low surface tension generally have more pneumotoxic potential
ADME of petroleum products?
A=readily from GI mucosa, intact skin, inhalation M=aliphatic hydrocarbons–in liver by oxidation and aromatic hydrocarbons–by hydroxylation to phenols and carboxylic acids E=volatile aliphatic hydrocarbons–partly by lungs and aromatic hydrocarbons–as conjugates with glucuronic acid, sulfuric acid, or glycine in urine or bile note: oily substance aspirated into lungs cannot be eliminated by coughing or ciliary activity
T/F Absorption is inversely proportional to molecule weight.
TRUE
Aromatic hydrocarbons are _____ readily absorbed than aliphatic hydrocarbons.
more
Effects of petroleum product toxicosis?
aspiration pneumonia, inhalation causes chemical pneumonitis, GI tract signs, systemic effects such as CNS depression, liver/kidney damage, bone marrow suppression (aromatic hydrocarbons)
MOA behind aspiration pneumonia in petroleum toxicosis?
ingestion of irritant oils leads to vomiting resulting in asp pneumonia; animals may not vomit; direct contact causes rapid dissolution of the lipid part of cell membranes resulting in swelling, edema, bronchoconstriction and necrosis; death d/t anoxemia and possible toxemia from bact infection of lungs
MOA behind GI signs in petroleum toxicosis?
direct irritation of GI mucosa causes V+, D+ and colic recall for V+: animals considered nonemetic horse, rat, rabbits, guinea pigs and Japanese quail
Some hydrocarbons such as chloroform sensitive the myocardium to ___________.
endogenous catecholamines
Clinical signs of petroleum product toxicosis?
signs of asp pneumonia such as shivering, incoordination, anorexia, weight loss, coughing, dyspnea and abnormal lung sounds; smell of oil or kerosene; oil in feces; CNS signs
Pathology of petroleum product toxicosis?
ulceration of tracheal mucosa, oil in bronchi/GI tract, degeneration and necrosis of liver/kidney (aliphatic hydrocarbons)
Lab diagnosis of petroleum product toxicosis?
oil in GI contents (floats on surface); aromatic hydrocarbons cause anemia, leukopenia and thrombocytopenia; rads demonstrate asp pneumonia
Differential diagnosis of petroleum product toxicosis?
other pneumonias
Prognosis of petroleum product toxicosis?
depends on severity; severe cases guarded to poor–d/t persistence of oil in lungs
Treatment of petroleum product toxicosis?
remove oil from body surface w/ soap/water; activated charcoal or mineral oil; cage rest; symptomatic/supportive therapy (resp support, ABs, fluid therapy, blood transfusion)
What is contraindicated in the treatment of petroleum product toxicosis?
emetics, gastric lavage, glucocorticoids
Uses of fluoride?
sodium fluoride–wood treatment; sodium fluoalmuniate–plant insecticide; hydrofluoric acid–industrial toxicant
Source of fluoride toxicosis?
industrial contamination of forages/pastures, natural waters, feed/mineral supplements, normal constituent of forages and plants that grow in fluoride rich soil (herbaceous part not seeds)
Properties of fluoride?
reacts w/ variety of other organic/inorganic compounds and has high affinity for calcium, aluminum, iron
T/F Acute fluoride toxicosis is more common than chronic fluoride toxicosis?
FALSE
What is another name for chronic fluoride toxicosis?
fluorosis
What species do you commonly see chronic fluoride toxicosis in?
herbivores esp dairy cattle
T/F Soluble sodium fluoride (NaF) is more toxic than calcium fluoride (CaF2).
TRUE
_______ animals are more sensitive to chronic fluoride toxicosis?
young–those developing bones and teeth!
ADME of fluoride?
A=intestinal tract D=throughout body, crosses placenta E=mainly urine
T/F Fluoride crosses the placenta and causes teratogenic effects.
FALSE–can cross placenta but generally the fetus is not affected
T/F Milk fluoride is readily absorbed via GIT tract.
FALSE–not readily absorbed
Where is fluoride mainly stored in the body?
bones and teeth (96%)–normal level in cattle bone is 1000-1500 ppm
Tissue fluoride can become elevated _______ times in toxicosis.
2-3 times
MOA of acute fluoride toxicosis?
caustic effect on GI mucosa, hypocalcemia, coag defects, increased capillary permeability, inhibition of many enzymes (cellular resp and energy)
MOA of chronic fluoride toxicosis?
Alternation and delaying of mineralization of teeth–damage to ameloblasts/odontoblasts, brown/black discoloration of defective enamel due to oxidation of organic material in teeth. Alteration and delaying of mineralization of bone–abnormal bone produced, osteoporosis.
Onset of action of acute fluoride toxicosis?
fast–within 30 minutes
Clinical signs of acute fluoride toxicosis?
gastroenteritis (may be hemorrhagic, excessive salivation, V+), urination/defecation, CNS stimulation and clonic seizures, stiffness and weakness, weight loss and decreased milk production, death from resp or cardiac failure
Onset of action of chronic fluoride toxicosis?
slow–6-12 months
Clinical signs of chronic fluoride toxicosis?
intermittent lameness, painful stiff gait, bony exostoses seen or felt on legs, spontaneous fractures, teeth mottling and patchy loss of dentine, brown color around eroded teeth areas, anorexia, emaciation, rough hair coat, reduced milk production and reproduction
Pathology of acute fluoride toxicosis?
hemorrhagic gastroenteritis, hemorrhages, congestion and edema of various organs–incl brain
Pathology of chronic fluoride toxicosis?
dental lesions most severe in developing teeth, bone lesions–hyperostosis, porous, enlargement, chalky white in appearance and roughening
Histopathologic changes in fluoride toxicosis?
uneven mineralization, excessive osteoid tissue, cortical thickening, and periosteal hyperostosis
Where do the bone lesions typically begin in chronic fluoride toxicosis?
bilaterally on the medial side of the proximal third of the metatarsals
Where do the bone lesions progress to in chronic fluoride toxicosis after metatarsals?
mandible, metacarpals, ribs, spine, and joints
Lab diagnosis of fluoride toxicosis?
chem analysis–>bone biopsy or necropsy, levels >1500 ppm, elevated urine levels confirm recent exposure, feed/water samples for fluoride. micro/rad exam of bone
What factors can help diagnose fluoride toxicosis?
history of exposure, intermittent lameness, dental/skeletal lesions, fluoride analysis
Differential diagnosis for fluoride toxicosis?
vit D deficiency, parathyroid dz
Treatment and prevention of fluoride toxicosis?
no known way to mobilize fluoride from bone, feed and water containing excess fluoride can be diluted w/ uncontaminated feed/water, etc.
Tolerance of fluoride can be increased by a balanced intake of what 3 things?
Ca, P, vit D
What can be given orally and will form insoluble compounds with fluoride in the gut preventing fluoride toxicosis?
aluminum salts, calcium carbonate, defluorinated phosphate
