Industrial toxins

1
Industrial toxins
2


Table 198-1 Agents Absorbed through Intact Skin That May Result in Systemic Toxicity
Acrylamide
Acrylonitrile, acetonitrile, propionitrile
Aniline
Chlordane
Dinitrophenol
Hydrocarbons benzene, gasoline, toluene, toluene diisocyanate, xylene (all slowly absorbed)
Hydrogen cyanide, cyanide salts
Hydrogen fluoride (hydrofluoric acid)
Metals (organic mercury, thallium)
Methyl bromide
Methylene chloride (slow)
Nerve agents
Nitrates
Nitrobenzene
Pesticides
Phenol
T2 toxin (biologic)
3
Table 198-3 Common Signs and Symptoms of Exposure to Hazardous Chemicals


Substances Symptoms Antidotes
Respiratory toxins Phosgene Chlorine Vinyl chloride Nitrogen oxides Ammonia Respiratory distress Pulmonary edema Supportive care
Metabolic toxins Cyanide Hydrogen sulfide Carbon monoxide Ricin Coma Seizures Cardiac arrest Cyanide kit for cyanides and hydrogen sulfide 100 oxygen or hyperbaric oxygenation for carbon monoxide
Hydrocarbons Halogenated hydrocarbons Aromatic hydrocarbons Confusion, lethargy Coma Cardiac dysrhythmias Respiratory distress Symptomatic treatment Avoid sympathomimetic agents
4
Respiratory toxins

• removal from the source, 100 oxygen, and inhaled
  bronchodilators for bronchospasm
• ABGs, EKG, CXR

5
Agent Findings Onset Irritant
Phosgene Pulmonary edema Delayed Mild/none
Organophosphates Increased secretions/bronchospasm Vapor immediate Mild
Organophosphates Increased secretions/bronchospasm Dermal liquid delayed Mild
Nitrogen dioxide Initial dyspnea and flulike symptoms Delayed Yes
Nitrogen dioxide Transient improvement Delayed Yes
Nitrogen dioxide Worsening dyspnea due to pulmonary edema 2472 h after exposure Delayed Yes
Chlorine Coughing, nausea and vomiting (low level) Immediate Yes
Chlorine Pulmonary edema (high level) Delayed Yes
Ammonia Coughing, hoarseness, bronchospasm Immediate Yes
Hydrogen sulfide Burning eyes and mucous membranes Immediate Yes
Hydrogen sulfide Pulmonary edema Delayed Yes
Cyanide Normal lung examination Immediate No
6
agents

• Phosgene
• Chemical warfare (poor warning signs)
• Acid burn to lower airways
• Dyspnea and chest tightness
• Is symptoms develop rapidly, poor prognosis
• Chlorine
• dense green-yellow gas that has an acrid, pungent
  odor (great warning signs)
• Ocular, upper airway irriation, coughing and
  horseness

7
ammonia

• Household cleaners
• highly water-soluble, colorless, alkaline,
  corrosive gas with a characteristic pungent odor
• Mucous membrane and eye irritation
• Supportive care

8
Cyanide

• Inhibits many metabolic processess
• binds (with very high affinity) to the ferric ion
  cytochrome a3 portion of cytochrome oxidase
  within the mitochonidria
• symptoms following inhalational exposure to
  hydrogen cyanide gas is immediate
• Bitter almonds smell
• Cherry red skin
• median lethal dose (LD50)
• estimated to be 200 ppm for a 30-minute exposure
• 600 to 700 ppm for a 5-minute exposure

9


Table 198-6 Signs and Symptoms of Acute Cyanide Toxicity
Cardiovascular
Tachycardia Mild
Hypertension
Bradycardia
Hypotension
Cardiovascular collapse
Asystole Severe
Central nervous system
Headache Mild
Drowsiness
Seizures
Coma Severe
Pulmonary
Dyspnea Mild
Tachypnea
Apnea Severe
10


Table 198-7 Anticipated Laboratory Findings in Cyanide Poisoning
Test Result Cause
Serum electrolytes Elevated anion gap Lactic acidosis from anaerobic metabolism
Arterial blood gases Metabolic acidosis Oxygenation initially normal
Arterial blood gases Normal PaO2 Oxygenation initially normal
Lactate gt10 mmol/L Correlates with toxic cyanide level
Measured oxygen saturation by co-oximetry Normal Hemoglobin retains normal oxygen-carrying capacity
Measured arterial-mixed venous oxygen difference Decreased Decreased tissue oxygen consumption
Whole-blood cyanide level Toxic gt0.5 microgram/mL Note plasma cyanide levels are roughly one tenth of the whole-blood cyanide levels
Whole-blood cyanide level Fatal gt2.5 micrograms/mL Note plasma cyanide levels are roughly one tenth of the whole-blood cyanide levels
Fire victims Elevated carboxyhemoglobin level Carbon monoxide generated by incomplete combustion
Fire victims Elevated carboxyhemoglobin level Synergistic toxicity with cyanide
11
treatment

• Supportive care first
• ampules of amyl nitrite for inhalation
• 10-mL vials of 3 sodium nitrite (300 milligrams)
• 50-mL vials of 25 sodium thiosulfate (12.5
  grams)
• Nitrites remove cyanide form cytochrome, and
  ampule not necessary if iv access
• Hydroxocobalamin (vitamin B12a), 5 grams (or 70
  milligrams/kg) IV over 30 minutes), in
  combination with sodium thiosulfate

12
References

• Tintinalli, Ch. 198