Industrial toxins: Petroleum products Dr. Bergfelt Flashcards
What are types of petroleum products
Sweet crude oil: rich in low-temp distillates such as gasoline, kerosene & naptha
Sour crude oil: high sulfer high-temp distillates such as lubricating oil & gas oil
How are types of refined petroleum products classified
Aliphatic HCs
- Short-chain (<5 carbons)
* e.g. methane, ethane, propane, butane pentane - Long-chain (>=5 carbons)
* gasoline, kerosene, petroleum distillates, mineral oil, turpentine, etc
Chlorinated aliphatic HCs
- CCl4, chloroform etc (dry cleaning & degreasing solutions)
Aromatic or plycyclic aromatic HCs (PAH)
- quick-dry paints, reins, glues, platics (e.g. benzene, toluene & xylene)
How are plastics manufactured
from HC gas liquids (HGL) & natural gas not crude oil
HGL are byproducts of petroleum refining & natural gas processing
properties of petroleum products
Both crude oil & refned products are highly irritating to the skin & mucous membranes
Oily in nature (lipophilic)
some oils may contain chlorinated naphthalenes (very stable) & can cause bovine skin hyperkeratosis)
toxicity of petroleum products
Generally high boiling points (low volatility) such as asphalt, mineral oil or waxes are relatively non-toxic d/t poor absorption
More volatile = more toxic because of more absorption, especially through inhalation
Low boiling points, low viscosity and low surface tension generally have more pneumotoxic (lung) effects and impaired respiration
lethality of crude oil
Sweet vs Sour
Sweet crude (gasoline) is more lethal than Sour curde (lubricating oil)
minimal lethal dose based on death caused by aspiration pneumonia over a week:
Sweet crude oil, 48 mL/kg
Sour crude oil, 74 mL/kg
What spp susceptible to crude petroleum substances
Cattle are the most susceptible
Small animals (targeted and non-targeted) are
most frequently poisoned
Terrestrial and aquatic wildlife and birds are highly
susceptible to oil spills
Toxicokinetics of petroleum
Readily absorbed from the GI mucosa, through skin (lipophilic) and by inhalation (volatility)
Absorption is inversely proportional to molecular weight (i.e., ↓MW/↑Absorption)
Polycyclic aromatic hydrocarbons (PAH) are morereadily absorbed than aliphatic hydrocarbons
MoA of petroleum
Aspiration pneumonia or chemical pneumonitis
Death is due to hypoxia and possible toxemia from secondary bacterial infection in the lungs (bacterial pneumonia)
Oily substances aspirated into the lungs cannot be eliminated by
coughing or ciliary activity
Aspiration pneumonia is bronchopneumonia that develops due to
the entrance of foreign materials into the bronchial tree, usually
involves oral or gastric contents due to vomiting or regurgitation
systemic effect of petroleum
The main systemic toxic effect is CNS depression
Other systemic effects include liver/kidney damage
Chronic exposure with aromatic hydrocarbons causes bone marrow suppression
Some hydrocarbons such as chloroform sensitize the myocardium to endogenous catecholamines resulting in cardiac arrhythmias and cardiac arrest
typical lesions seen w/ petroleum
lesions of aspiration pneumonia
Tx for petroleum
Removal of the oil on the body surfaces by soap & warm water
Activated charcoal or mineral oil
Symptomatic and supportive therapy (respiratory support, antibiotics, fluid therapy, blood transfusion)
Rest
Contraindicated: emetics and gastric lavage (aspiration pneumonia) and glucocorticoids
