Signs and symptoms of hydrogen sulfide poisoning stem from the contact with very high concentrations of this colorless gas (mainly through inhalation) which causes disruption of adenosine triphosphate (ATP) production in the mitochondria [1] [2] [3] [4]. Most cases of poisoning occur in the occupational settings and after carbon monoxide (CO), hydrogen sulfide (H2S) is the second most common cause of work-related death due to gas poisoning [4]. Individuals involved in agriculture, sewage processing, or those who are in regular contact with petroleum have shown to be exposed to significant concentrations of this gas [1] [4]. On the other hand, active volcanoes are a natural source of H2S, meaning that people living in the proximity of volcanoes may also be at risk [4]. Moreover, suicides or intentional poisoning (hydrogen sulfide is listed as a chemical weapon) have also been reported [1] [3]. Hydrogen sulfide poisoning manifests acutely in most cases. The central nervous system (CNS) and the respiratory system (lungs) are the two main organ systems where hydrogen sulfide exerts its toxic effects [4] [5]. Headaches, nausea, vomiting, changes in coordination, and even loss of consciousness are frequent manifestations, while pulmonary edema with subsequent hypoxemia and respiratory depression are main findings involving the respiratory system [4] [6]. Because H2S is able to block calcium channels in the heart, cardiac function can be impaired and lead to ventricular fibrillation or even death from cardiogenic shock in some patients [7] [8] [9].

• Unconsciousness

  Will become unconscious in 3 to 5 minutes. Immediate artificial resuscitation is required. 700 ppm Breathing will stop and death will result if not rescued promptly, immediate unconsciousness. [alken-murray.com]

  Abstract A 25-year-old man, a field operator in a petroleum refinery was found unconscious. [jstage.jst.go.jp]

  At high concentrations, only a few breaths are needed to induce unconsciousness, coma, respiratory paralysis, seizures, even death. [blacklinesafety.com]

  Author: Gloyna, DF ; Wade, J Abstract: Hydrogen Sulfide (H2S) is a colorless, poisonous gas capable of rapidly causing dizziness, unconsciousness, respiratory paralysis, permanent brain damage and death. [archive.rubicon-foundation.org]

  "Releasing hydrogen sulphide in an aircraft cabin wouldn't render everyone unconscious," he explains. "There simply wouldn't be enough of the gas. [abc.net.au]

• Fatigue

  Death may occur after 48 hours. 100-150 Loss of smell (olfactory fatigue or paralysis). 200-300 Marked conjunctivitis and respiratory tract irritation after 1 hour. [osha.gov]

  With the sense of smell fatigued, those exposed fail to get warning of high concentrations, leading to respiratory paralysis and sudden collapse [3]. [scienceblogs.com]

  This condition, known as olfactory fatigue, can also occur when people have been exposed to hydrogen sulfide for a longer period of time. Hydrogen sulfide is heavier than air, so it can build up in low-lying areas and enclosed spaces. [doh.wa.gov]

  Chronic poisoning (repeated exposure to low levels) may result in symptoms that include slowed pulse rate, fatigue, insomnia, cold sweat, eye infections, loss of weight and skin eruptions. [cupe.ca]

  Those with asthma will experience airway constriction. 20 ppm Severe headaches, dizziness, memory loss, irritability and fatigue occur at 20 ppm exposure. 50 to 100 ppm When hydrogen sulfide gas becomes this concentrated, it will cause lung and eye irritation [gdscorp.com]

• Cough

  At low to moderate levels, signs and symptoms of hydrogen sulfide poisoning may include: irritation of the eyes, nose, and throat headache dizziness nausea vomiting coughing difficulty breathing Exposure to higher levels of hydrogen sulfide may lead to [schmidtandclark.com]

  Chronic, repeated, lower-level hydrogen sulfide exposure is associated with hypotension, headache, nausea, loss of appetite, weight loss, ataxia, conjunctivitis, chronic cough, and neuropsychological disorders. [merckvetmanual.com]

  Inflammation within the throat area causing coughing, sneezing, excess mucus production, hoarseness, lethargy Dyspnoea Having difficulty breathing Cardiovascular Effects: Chest pain Pain and discomfort within the chest area Cardiac Arrhythmia Having [firstaidcalgary.ca]

  May cause digestive upset and loss of appetite. 100 Coughing, eye irritation, loss of smell after 2-15 minutes (olfactory fatigue). Altered breathing, drowsiness after 15-30 minutes. Throat irritation after 1 hour. [osha.gov]

  Exposure To Low Levels (10 ppm or less) Common effects of inhaling low concentrations of hydrogen sulfide (10 ppm or less) are burning eyes, coughing and shortness of breath. [vividlearningsystems.com]

• Respiratory Insufficiency

  The preponderance of scientific evidence suggests that permanent central nervous system sequelae result from hypoxia secondary to respiratory insufficiency (Beauchamp, et al., 1984; Milby & Baselt, 1999a; Riffenstein, et al., 1992). [experts.com]

• Nausea

  Nausea and vomiting are also common. Chronic, repeated, lower-level hydrogen sulfide exposure is associated with hypotension, headache, nausea, loss of appetite, weight loss, ataxia, conjunctivitis, chronic cough, and neuropsychological disorders. [merckvetmanual.com]

  Symptoms may include: Nausea An uncomfortable feeling in the stomach that can cause vomiting Headaches Pain and discomfort within the back of the head, upper neck, front of the head, or sides of the head Delirium State of confusion and the inability to [firstaidcalgary.ca]

  Headaches, nausea, vomiting, changes in coordination, and even loss of consciousness are frequent manifestations, while pulmonary edema with subsequent hypoxemia and respiratory depression are main findings involving the respiratory system. [symptoma.com]

  At low to moderate levels, signs and symptoms of hydrogen sulfide poisoning may include: irritation of the eyes, nose, and throat headache dizziness nausea vomiting coughing difficulty breathing Exposure to higher levels of hydrogen sulfide may lead to [schmidtandclark.com]

  Other low-level symptoms include nervousness, dizziness, nausea, headache and drowsiness. [nachi.org]

• Vomiting

  Headaches, nausea, vomiting, changes in coordination, and even loss of consciousness are frequent manifestations, while pulmonary edema with subsequent hypoxemia and respiratory depression are main findings involving the respiratory system. [symptoma.com]

  At low to moderate levels, signs and symptoms of hydrogen sulfide poisoning may include: irritation of the eyes, nose, and throat headache dizziness nausea vomiting coughing difficulty breathing Exposure to higher levels of hydrogen sulfide may lead to [schmidtandclark.com]

  Moderate concentrations cause more severe eye and respiratory effects, headache, dizziness, nausea, vomiting, coughing and difficulty breathing. High concentrations can lead to shock, convulsions and inability to breathe. [safetyandhealthmagazine.com]

  Sources told the TV station at the time investigators suspected carbon monoxide as their cause of death after finding vomit in the car and rash-like splotches on the bodies. [nydailynews.com]

  Moderate concentrations can cause more severe eye and respiratory irritation, headache, dizziness, nausea, and vomiting. Brief exposures to high concentrations of hydrogen sulfide can cause loss of consciousness, coma, and possible death. [doh.wa.gov]

• Hypotension

  Symptoms 0.05 ppm (airbone concentration) Pungent smell mimicking “rotten egg” 0.1 ppm Anosmia 50-150 ppm Paralysis, conjunctivitis 250 ppm Photophobia, pulmonary edema 250-500 ppm Headache, nausea, vomiting, confusion, tachycardia, hypotension 500-750 [slideshare.net]

  Chronic, repeated, lower-level hydrogen sulfide exposure is associated with hypotension, headache, nausea, loss of appetite, weight loss, ataxia, conjunctivitis, chronic cough, and neuropsychological disorders. [merckvetmanual.com]

  Apnea usually precedes bradycardia and hypotension, and decorticate posturing may be noted prior to death. Hydrogen sulfide in high doses also causes abrupt loss of consciousness with convulsions. Direct damage to myocardium may be prominent. [msdmanuals.com]

  Impairment in the metabolic system can cause: Increased blood lactate concentration Is an indicator of having the body going through shock Associated with tachycardia, hypotension, cold and clammy skin Decrease in oxygen uptake Can lead to hypoxia Hydrogen [firstaidcalgary.ca]

• Tachycardia

  Impairment in the metabolic system can cause: Increased blood lactate concentration Is an indicator of having the body going through shock Associated with tachycardia, hypotension, cold and clammy skin Decrease in oxygen uptake Can lead to hypoxia Hydrogen [firstaidcalgary.ca]

  Symptoms and Signs Cyanide initially causes gasping, tachycardia, and hypertension. Loss of consciousness and convulsions may occur in as little as 30 seconds. [msdmanuals.com]

  Symptoms 0.05 ppm (airbone concentration) Pungent smell mimicking “rotten egg” 0.1 ppm Anosmia 50-150 ppm Paralysis, conjunctivitis 250 ppm Photophobia, pulmonary edema 250-500 ppm Headache, nausea, vomiting, confusion, tachycardia, hypotension 500-750 [slideshare.net]

  Signs and Symptoms of Acute Hydrogen Sulfide Exposure: Signs and symptoms of acute exposure to hydrogen sulfide may include tachycardia (rapid heart rate) or bradycardia (slow heart rate), hypotension (low blood pressure), cyanosis (blue tint to skin [cameochemicals.noaa.gov]

• Cyanosis

  On the other hand, some victims of hydrogen sulfide poisoning exhibit frank cyanosis, suggesting that the respiratory tract obstruction is more common in this condition than is generally recognized. [ncbi.nlm.nih.gov]

  Cyanosis may be present. Hydrogen sulfide inhalation is associated with cardiac arrhythmias. Nausea and vomiting are also common. [merckvetmanual.com]

  Signs and Symptoms of Acute Hydrogen Sulfide Exposure: Signs and symptoms of acute exposure to hydrogen sulfide may include tachycardia (rapid heart rate) or bradycardia (slow heart rate), hypotension (low blood pressure), cyanosis (blue tint to skin [cameochemicals.noaa.gov]

• Chest Pain

  pain or tightness Stomach pain, vomiting Headache Increased redness, pain or pus from the area of a skin burn It is important to remain vigilant and avoid complacency with your safety program. [blacklinesafety.com]

  pain Pain and discomfort within the chest area Cardiac Arrhythmia Having your heart beat abnormally Electrical signals that control normal heart rate is compromised Two types of arrhythmia: Tachycardia – heart is beating way too fast above normal; Bradycardia [firstaidcalgary.ca]

  During these episodes there were frequent health complaints including eye, throat and lung irritation, nausea, headache, nasal blockage, sleeping difficulties, weight loss, chest pain, and asthma attacks. [health.ny.gov]

• Heart Disease

  […] that is approximately over 140/90 mmHg where normal is below 120/80 mmHg Chronic hypertension can cause atherosclerosis (hardening of arterial walls), heart disease, kidney disease, stroke, damage to the eye Victim may be asymptomatic (no physical symptoms [firstaidcalgary.ca]

• Lacrimation

  […] source; can cause headaches, nausea and other symptoms Keratoconjunctivitis Inflammation of the cornea and conjunctiva Blepharospasm Muscle spasms that control the eyelid which causes uncontrollable blinking or complete inability to open the eye lids Lacrimation [firstaidcalgary.ca]

  Exposure to hydrogen sulfide gas may result in skin irritation, lacrimation (tearing), inability to detect odors, photophobia (heightened sensitivity to light), and blurred vision. [cameochemicals.noaa.gov]

• Blurred Vision

  vision, dizziness, nausea Neurological Effects: Neurological effects may be acute or chronic, having the potential to be permanent depending on the severity of exposure. [firstaidcalgary.ca]

  Exposure to hydrogen sulfide gas may result in skin irritation, lacrimation (tearing), inability to detect odors, photophobia (heightened sensitivity to light), and blurred vision. [cameochemicals.noaa.gov]

• Excessive Tearing

  tears shed than normal Metabolic Effects: Hydrogen sulfide can impair the body’s metabolic system in relation to how the body uses oxygen to aid in physiological functioning. [firstaidcalgary.ca]

• Headache

  This compound causes acute toxicity of the lungs and central nervous system, producing manifestations such as a headache, dizziness, changes in consciousness, and respiratory depression with hypoxemia. [symptoma.com]

  Once the exposure threshold reaches 30 ppm, the smell becomes very sweet and sickening. 2 to 5 ppm Prolonged exposure at this level will result in headaches, watery eyes, nausea and sleep problems. [gdscorp.com]

  Impact on health (long-term) Those having prolonged exposure to high enough levels of H2S gas to cause unconsciousness may continue to experience headaches, reduced attention span and motor functions. [blacklinesafety.com]

  Above 30 ppm, odor described as sweet or sickeningly sweet. 2-5 Prolonged exposure may cause nausea, tearing of the eyes, headaches or loss of sleep. [osha.gov]

  In some individuals, there have been permanent or long-term effects such as headaches, poor attention span, poor memory, and poor coordination. [doh.wa.gov]

• Dizziness

  This compound causes acute toxicity of the lungs and central nervous system, producing manifestations such as a headache, dizziness, changes in consciousness, and respiratory depression with hypoxemia. [symptoma.com]

  Author: Gloyna, DF ; Wade, J Abstract: Hydrogen Sulfide (H2S) is a colorless, poisonous gas capable of rapidly causing dizziness, unconsciousness, respiratory paralysis, permanent brain damage and death. [archive.rubicon-foundation.org]

  At low to moderate levels, signs and symptoms of hydrogen sulfide poisoning may include: irritation of the eyes, nose, and throat headache dizziness nausea vomiting coughing difficulty breathing Exposure to higher levels of hydrogen sulfide may lead to [schmidtandclark.com]

  Long-term, low level exposure to hydrogen sulfide may result in fatigue, loss of appetite, headaches, irritability, poor memory, and dizziness. More Information Hydrogen Sulfide ToxFAQs, ATSDR Hydrogen Sulfide, OSHA Fact Sheet (PDF) [doh.wa.gov]

  Other low-level symptoms include nervousness, dizziness, nausea, headache and drowsiness. [nachi.org]

• Seizure

  At high concentrations, only a few breaths are needed to induce unconsciousness, coma, respiratory paralysis, seizures, even death. [blacklinesafety.com]

• Giddiness

  Neurological effects include giddiness, irritability, drowsiness, weakness, confusion, delirium, amnesia, headache, sweating, and dizziness. Muscle cramping, tremor, excessive salivation, cough, convulsions, and coma may be noted. [cameochemicals.noaa.gov]

• Agitation

  Sub-acute exposure (exposure to lower levels) may result in headaches, dizziness, loss of balance, agitation, nausea, diarrhea. [cupe.ca]

A detailed patient history is the essential part of the diagnostic workup in patients with hydrogen sulfide poisoning. The physician needs to cover the course of symptoms, their progression, and determine if they may have occurred as a result of exposure at the workplace. If there is suspicion of intentional poisoning, a heterogeneous anamnesis from parents, close relatives, partners, or friends might be useful. A physical examination can further reveal neurological impairment, cardiac disturbances, and respiratory difficulties.

Spirometry, electrocardiography, as well as measurements of blood pressure and echocardiography, are important features of hydrogen sulfide poisoning workup, but significant changes may not always be present [8] [10] [11]. In order to make a definite diagnosis, specific biochemical tests need to be employed. Gas chromatography-mass spectrometry (GC-MS), a tool that is able to detect the concentration of many substances including gases, is the promising method for the diagnosis of hydrogen sulfide poisoning [3] [5]. Blood and urine are used as samples for a measurement of hydrogen sulfide metabolites [3].

Adjuncts used in the treatment of cyanide poisoning have been advocated because of the shared mechanism of toxicity between hydrogen sulfide and cyanide. [ncbi.nlm.nih.gov]

Additionally, administration of nitrites has been widely used in the treatment of H2S poisoning (2). This treatment should be initiated with inhalation of amyl nitrite until sodium nitrite can be injected intravenously (22). [apjmt.mums.ac.ir]

Major outcomes occurred in eight cases, along with six deaths. [6] Prognosis Low-level exposures to hydrogen sulfide usually produce local eye and mucous membrane irritation, while high-level exposures rapidly produce fatal systemic toxicity. [7] Exposures [emedicine.medscape.com]

For a more complete discussion of the diagnosis and prognosis of RADS, the reader is invited to go to: http://toxicology.leadingexperts.com//rads.html. For a complete list of references, please contact Dr. Thomas Milby Dr. Thomas H. [experts.com]

Moreover, it was found that patients with suicidal attempt had poorer prognosis and needed to more aggressive treatments compared to patients with secondary exposure. [apjmt.mums.ac.ir]

Etiology Hydrogen sulfide most often is encountered as a byproduct of the petroleum, viscose rayon, rubber, and mining industries. [1] The petroleum industry is responsible for most cases of hydrogen sulfide toxicity in North America. [emedicine.medscape.com]

In the author's experience, the term RADS is often used imprecisely to describe a host of pulmonary problems that bear little or no relationship, either clinically or etiologically, to the syndrome describe by Brooks and his colleagues. [experts.com]

Seite 69 - Epidemiology is defined as the study of the distribution and determinants of health-related states or events in specified populations, and the application of this study to control of health problems. ‎ [books.google.de]

The objective of this study was to describe the epidemiologic profile of an outbreak of H2S suicides in Japan. [apjmt.mums.ac.ir]

These are mixed in an enclosed space, such as a closet or an automobile, and despite the fact that suicide victims often place warning signs on closet doors or car windows, rescue workers and others entering the space have been affected. [3] Epidemiology [emedicine.medscape.com]

Pathophysiology Significant hydrogen sulfide poisoning usually occurs by inhalation. Local irritant effects, along with arrest of cellular respiration, may follow. [emedicine.medscape.com]

The preventive measures that should be adopted to avoid this type of poisoning are stressed. [ncbi.nlm.nih.gov]

How did the exposure occur, and what could’ve been done to prevent it? Like this post? Subscribe to our blog to get content delivered to your inbox. [vividlearningsystems.com]

Eyes: Wear appropriate eye protection to prevent eye contact with the liquid that could result in burns or tissue damage from frostbite. [cameochemicals.noaa.gov]

Inhalation: Take precautions to prevent a fire (e.g. remove sources of ignition). Take precautions to ensure your own safety before attempting rescue (e.g. wear appropriate protective equipment). Move victim to fresh air. [ccohs.ca]

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