Since benzene is frequently used in industrial processes and is present in gasoline, workers employed in chemical plants and gas stations are most likely to be exposed to it; however, it is also present in the general environment, being released from paints, automobile exhausts, and cigarette smoke. Its concentration is higher indoors than outdoors, especially in homes where there are smokers.

Apart from workplace accidents, acute poisoning can follow unintentional consumption or inhalation of benzene or benzene-containing solutions at home, usually by children; exposure can also occur by intentional use of hydrocarbons, such as recreational abuse, or suicide attempts.

Acute ingestion or inhalation of benzene affects mainly the central nervous system (CNS) and is believed to be mediated by benzene itself, although there are claims [1] that benzene’s metabolites may also play a role. The signs are similar to alcohol intoxication and are the same irrespective of whether the chemical is inhaled or ingested, except for the irritation of the mucous membranes of the respiratory tract when the route is by inhalation. Also, according to some reports [2] the lethal dose (LD50) is higher by two orders of magnitude for hydrocarbons entering the body by ingestion than by inhalation. Therefore, aspiration of benzene-containing liquids, including vomitus is a major hazard. Mild exposure results in a headache, dizziness, euphoria, nausea, vomiting, tightness in the chest, and dyspnea. Higher concentrations may cause visual problems, ventricular fibrillation, paralysis, tremor, convulsions, or loss of consciousness [3]. Death can occur after large doses of benzene due to ventricular fibrillation.

In contrast to acute poisoning, the chronic effects of benzene on the cells of the hematopoietic system are mediated by its metabolic products [4]. All of these are oxidized derivatives (phenol, hydroquinone, catechol, benzenetriol, hydroquinone, and trans-Muconic acid). These are reactive chemical species and may contribute to benzene’s effects through different pathways, making the mechanism of toxicity a complex issue [5]. Patients suffering from chronic exposure present with general symptoms. These can include fatigue, weight loss, headaches, dizziness, weakness, pale skin, bleeding gums, nosebleeds, and bruising.

Chronic exposure to benzene may result in dysfunction of the hematopoietic system due to the chemical interfering with renewal and differentiation of stem cells; consequently, both anemic and leukemic diseases may develop [6].

Patients with chronic exposure may display signs of anemia and poor immunity. Sometimes, the condition of aplastic anemia caused by benzene exposure includes symptoms of hemolysis, such as mild bilirubinemia, shortened erythrocyte life-cycle and similar signs that are not present in idiopathic disease [7].

Leukemia may follow pancytopenia or aplastic anemia in about a quarter of the leukemia patients [7], often after a lag of several years [8]. Case reports and epidemiological studies demonstrate a variety of responses to chronic benzene exposure: both acute and chronic leukemias and other disorders are found. For example, among 74,828 people exposed to benzene, 82 were identified with hematopoietic diseases, with cases of acute leukemia, myelodysplastic syndrome, chronic granulocytic leukemia, malignant lymphoma and aplastic anemia [9]. In another study, among 28,460 people working in factories where they were exposed to benzene, 30 cases of leukemia were found, most of which were of the acute type [10]. The International Agency for Research on Cancer has determined that benzene is a carcinogen.

• Exposure to Benzene

  Assessment of exposure to benzene was carried out in 672 factories in 12 cities in China. Historical exposure data were collected for 3179 unique job titles. [ncbi.nlm.nih.gov]

  Effects of Benzene Exposure Exposure to benzene can have several harmful effects on individuals. [seegerweiss.com]

  The most common avenue of inhalation exposure to benzene is via cigarette smoke - first or second hand. [benzeneweb.com]

  Benzene Poisoning Long-term exposure to benzene can result in the development of several conditions and diseases including: Anemia - a condition in which the number of red blood cells is diminished. [impactlaw.com]

• Anemia

  CBP could give the appearance of different types of disorders such as leukopenia, agranulocytosis, anemia, pancytopenia, aplastic anemia (AA), myelodysplastic syndrome (MDS), and leukemia. [ncbi.nlm.nih.gov]

  Year History of Benzene Toxicity: Aplastic Anemia and Leukemia 1897 Santeson - aplastic anemia; established benzene as powerful bone marrow poison 1903 LeNoir - leukemia in benzene workers 1911 Setting - benzene a bone marrow poison in rabbit bioassays [digitalsynergy.com]

  Benzene has been identified as a carcinogen, and long-term exposure can lead to benzene poisoning, which can cause anemia, lymphoma, and leukemia, a form of cancer. [impactlaw.com]

  After chronic exposure, hematologic disorders such as pancytopenia, aplastic anemia, and acute myelogenous leukemia and its variants may occur. [mhmedical.com]

• Fatigue

  Exposure to benzene at work can cause immediate symptoms such as headache, fatigue, nausea and dizziness. [duncanlewis.co.uk]

  Acute Effects of Lead Poisoning • Fatigue • Headache • Irritability • Metallic taste in mouth • Poor appetite • Reproductive problems • Sleeplessness • Stomach upset 32. [slideshare.net]

  The patient over time begin to bother: fatigue; insomnia weakness; malaise; irritability; dizziness; insomnia; headache; noise in the head and ears; increased heart rate. Then joins nausea, vomiting, pain in the bones. [en.intoxication-stop.com]

  These can include fatigue, weight loss, headaches, dizziness, weakness, pale skin, bleeding gums, nosebleeds, and bruising. [symptoma.com]

  Nearly a decade of chemotherapy, along with diabetes and a rare bowel disorder, have left him battling what he calls “absolutely ridiculous” fatigue. Retired and on disability, he remembers returning to work twice. [publicintegrity.org]

• Gastric Lavage

  lavage ) Washing of the skin (irrigation) -- perhaps every few hours for several days You may be admitted to the hospital if the poisoning is severe. [indiatoday.in]

  Gastric lavage may be preferable to emesis if large amounts of benzene have been ingested or if the patient is seen more than 1 hour after ingestion. [nap.edu]

• Vomiting

  If someone has swallowed benzene, do not try to make them vomit or give them fluids to drink. Also, if you are sure the person has swallowed benzene, do not attempt CPR. Performing CPR on someone who has swallowed benzene may cause them to vomit. [rxwiki.com]

  Followed, may have nausea, vomiting, palpitations, instability of walking, trance, just like drunkenness 9. [slideshare.net]

  which can lead to breathing problems if the benzene-contaminated vomit enters the victim’s lungs Drowsiness Convulsions and Death Serious Health Problems Due to Long-Term Benzene Exposure If the victim has been exposed to benzene for one year or more [napolilaw.com]

  For ingestion exposures, seek medical help immediately and do not induce vomiting. Certain jobs typically experience elevated benzene exposure risk. [benzeneweb.com]

• Nausea

  Toxic effect caused by exposure to benzene through contact, inhalation, or ingestion, characterized by disorientation, dizziness, headache, and/or nausea. In severe cases it can cause death through respiratory failure . [businessdictionary.com]

  Yet, some of the more common symptoms caused by benzene are: pallor tremors euphoria dizziness petechiae headache weakness staggering tachypnea drowsiness palpitations convulsions nervousness appetite loss blurred vision chest tightness nausea, vomiting [healthblurbs.com]

  Clinical presentation Acute exposure may cause immediate CNS effects, including headache, nausea, dizziness, tremor, convulsions, and coma. [mhmedical.com]

  Followed, may have nausea, vomiting, palpitations, instability of walking, trance, just like drunkenness 9. [slideshare.net]

  Among other symptoms are vomiting, loss of appetite and nausea. It may also cause irregular heartbeat and rapid, shallow breathing or even experience a tight chest. [ukaccidentatwork.co.uk]

• Abdominal Pain

  pain, occasionally bloody diarrhea, can cause serious liver and kidney damage 54. [slideshare.net]

  Individuals that have ingested food or water contaminated with benzene may experience nausea, vomiting, stomach irritation, abdominal pain, convulsions, and death. [schmidtandclark.com]

• Blurred Vision

  Yet, some of the more common symptoms caused by benzene are: pallor tremors euphoria dizziness petechiae headache weakness staggering tachypnea drowsiness palpitations convulsions nervousness appetite loss blurred vision chest tightness nausea, vomiting [healthblurbs.com]

  One may experience blurred vision and inflammation of nose and throat. Among other symptoms are vomiting, loss of appetite and nausea. It may also cause irregular heartbeat and rapid, shallow breathing or even experience a tight chest. [ukaccidentatwork.co.uk]

  […] benzene poisoning a toxic condition caused by ingestion of benzene, inhalation of benzene fumes, or exposure to benzene-related products such as toluene or xylene, characterized by blurred vision, nausea, headache, dizziness, and incoordination. [medical-dictionary.thefreedictionary.com]

  EYES, EARS, NOSE, AND THROAT Blurred vision Burning sensation in the nose and throat STOMACH AND INTESTINES Loss of appetite Nausea and vomiting HEART AND BLOOD Irregular heartbeat Rapid heartbeat Shock and collapse LUNGS AND CHEST Rapid, shallow breathing [stlukes-stl.com]

  Symptoms Eyes, ears, nose, and throat: Blurred vision Burning sensation in the nose and throat Gastrointestinal: Loss of appetite Nausea Vomiting Heart and blood: Irregular heartbeat Rapid heartbeat Lungs and chest: Rapid, shallow breathing Tight chest [indiatoday.in]

• Muscle Weakness

  weakness, hyperkeratosis and hyperpigmentation of the skin, as well as paresthesia in hands and feet 48. [slideshare.net]

• Euphoria

  Yet, some of the more common symptoms caused by benzene are: pallor tremors euphoria dizziness petechiae headache weakness staggering tachypnea drowsiness palpitations convulsions nervousness appetite loss blurred vision chest tightness nausea, vomiting [healthblurbs.com]

  There is dizziness, EUPHORIA, headache, weakness, trembling, clumsiness, tightness in the chest, coma and convulsions. Long-term, small-dose poisoning causes loss of appetite, irritability, severe ANAEMIA, LEUKAEMIA and LYMPHOMAS. [medical-dictionary.thefreedictionary.com]

  STOMACH AND INTESTINES Loss of appetite Nausea and vomiting HEART AND BLOOD Irregular heartbeat Rapid heartbeat Shock and collapse LUNGS AND CHEST Rapid, shallow breathing Tightness in the chest NERVOUS SYSTEM Dizziness Drowsiness Nervousness Convulsions Euphoria [stlukes-stl.com]

  […] sensation in the nose and throat Gastrointestinal: Loss of appetite Nausea Vomiting Heart and blood: Irregular heartbeat Rapid heartbeat Lungs and chest: Rapid, shallow breathing Tight chest Nervous system: Dizziness Drowsiness Nervousness Convulsions Euphoria [indiatoday.in]

  […] vision Burning sensation in the nose and throat HEART AND BLOOD Irregular heartbeat Rapid heartbeat Shock and collapse LUNGS AND CHEST Rapid, shallow breathing Tightness in the chest NERVOUS SYSTEM Dizziness Drowsiness Nervousness Convulsions (seizures) Euphoria [arh.adam.com]

• Headache

  […] benzene poisoning a toxic condition caused by ingestion of benzene, inhalation of benzene fumes, or exposure to benzene-related products such as toluene or xylene, characterized by blurred vision, nausea, headache, dizziness, and incoordination. [medical-dictionary.thefreedictionary.com]

  Toxic effect caused by exposure to benzene through contact, inhalation, or ingestion, characterized by disorientation, dizziness, headache, and/or nausea. In severe cases it can cause death through respiratory failure . [businessdictionary.com]

  Acute Effects of Lead Poisoning • Fatigue • Headache • Irritability • Metallic taste in mouth • Poor appetite • Reproductive problems • Sleeplessness • Stomach upset 32. [slideshare.net]

  Headache. Sense of constriction about the head and chest. [jamanetwork.com]

  Individuals who inhale or ingest high levels of benzene may go on to develop the following symptoms: confusion drowsiness dizziness irregular heartbeat irritation of the stomach headaches tremors unconsciousness vomiting Impact on long-term health Unfortunately [limepersonalinjury.co.uk]

• Dizziness

  […] benzene poisoning a toxic condition caused by ingestion of benzene, inhalation of benzene fumes, or exposure to benzene-related products such as toluene or xylene, characterized by blurred vision, nausea, headache, dizziness, and incoordination. [medical-dictionary.thefreedictionary.com]

  Toxic effect caused by exposure to benzene through contact, inhalation, or ingestion, characterized by disorientation, dizziness, headache, and/or nausea. In severe cases it can cause death through respiratory failure . [businessdictionary.com]

  These signs of benzene poisoning include: Confusion Irregular or rapid heartbeat Headache Unconsciousness Tremors Dizziness and Death Consuming benzene can also cause sudden health problems that develop in minutes or hours, which include the following [napolilaw.com]

  Some symptoms of inhalation may include: dizziness, increased/rapid heart rate, chronic headaches, muscle twitching or tremors, drowsiness, and unconsciousness. [legalinfo.com]

  Dizziness. Headache. Sense of constriction about the head and chest. [jamanetwork.com]

• Confusion

  How Benzene Poisoning Causes Damage to the Body When benzene is inhaled, it confuses the body’s cells into working improperly. [napolilaw.com]

  Toxic tort and injury laws are complex and confusing. The Metzger Law Group is here to help you. Call us today for a FREE evaluation to find out if you have a case or fill out our free evaluation forms to consult with a member of our caring staff. [digitalsynergy.com]

  As pointed out in the preface to this report, conditions other than benzene poisoning simulate it so closely that the diagnosis is frequently confused. [jamanetwork.com]

  Individuals who inhale or ingest high levels of benzene may go on to develop the following symptoms: confusion drowsiness dizziness irregular heartbeat irritation of the stomach headaches tremors unconsciousness vomiting Impact on long-term health Unfortunately [limepersonalinjury.co.uk]

  Dizziness, drowsiness, headaches, confusion, tremors, a feeling of intoxication, and loss of consciousness may occur. If ingested, individuals may experience vomiting, convulsions, and a dangerously increased heart rate. [benzeneweb.com]

• Seizure

  […] tightness Headache, lethargy Nausea, vomiting; appetite loss Vision abnormalities including blurry vision Increased or irregular heart-rate Feeling dizzy or drowsy Over-excitement, acting ‘drunk’ Lack of coordinated movements Low level of alertness Seizures [dovemed.com]

  Signs & Symptoms of Overexposure Severe stages: • Constant vomiting • Periods of stupor • Delirium • Seizures • Coma 30. [slideshare.net]

  Blurred vision Burning sensation in the nose and throat HEART AND BLOOD Irregular heartbeat Rapid heartbeat Shock and collapse LUNGS AND CHEST Rapid, shallow breathing Tightness in the chest NERVOUS SYSTEM Dizziness Drowsiness Nervousness Convulsions (seizures [arh.adam.com]

  Seizures may begin without any prodromal signs or symptoms. If the patient is paralyzed after intubation, electroencephalographic monitoring is warranted. [emedicine.medscape.com]

• Excitement

  Clinical manifestationsClinical manifestations Acute poisoning manifestations can be expressed as a two-stage: The first phase is the eyes, nose and throat irritation symptoms, as well as headache, nausea, excitement, exciting, who will soon re-occurrence [slideshare.net]

  Respiratory difficulties, which may be severe if the chemical is inhaled Chest pain and tightness Headache, lethargy Nausea, vomiting; appetite loss Vision abnormalities including blurry vision Increased or irregular heart-rate Feeling dizzy or drowsy Over-excitement [dovemed.com]

In acute cases, people displaying neurological symptoms of benzene poisoning should be monitored for inadequate oxygenation. Even if only small amounts have been inhaled or ingested, patients should be transferred to a healthcare facility for evaluation. For severely affected patients, toxicologists, and poison centers should be consulted.

Exposure to benzene can be detected by measuring the concentration in blood, exhaled breath, and urine; this – or routine blood work - can also be used to monitor workers in hazardous occupations. There is a linear relationship between benzene levels in the patients’ environment and in their biological samples [11]. However, measuring benzene itself may not be completely reliable when there has been exposure to only a low level. Urinary benzene metabolites (trans-Muconic acid and S-phenyl mercapturic acid) are more suited for the measurements of low exposures [12], and thus, for monitoring general populations [13]. Albumin adducts of benzene derivatives can be used to measure longer term exposure [14].

Since benzene is a hematopoietic toxin, detection of hematologic abnormalities by a complete blood count with differential, erythrocyte indices, and thrombocyte counts is the most basic examination. Patient history may reveal current or past occupational or environmental exposure to benzene. Further tests may be needed to exclude other forms of anemia. Examination of bone marrow can produce highly variable results in that patients can have hypoplastic or hyperplastic bone marrow [7] [15].

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