Benzene

Benzene: the toxic chemical causes blood cancer.

For many workers with acute myeloid leukaemia or myelodysplastic syndrome, their disease is caused by occupational exposure to benzene. Benzene is a highly toxic chemical that is widely used in the industrial sector. Workers exposed to benzene over an extended period of time are at particularly high risk of developing a range of blood disorders, including cancer.

Benzene: what it is and how it is used

Benzene is one of the twenty most widely used chemicals in industrial applications.

It can have a sweet odour or be completely odourless. Benzene is light yellow in its liquid state at room temperature. In its gaseous state, benzene can take the form of a colourless mist. Benzene is highly flammable and is a natural component of crude oil. As a result, many refined oil-based products contain benzene, including petrol, other fuels, solvents, paints, and glues. Moreover, benzene is widely used in the manufacture of many substances and products, including plastic, rubber, resins, lubricants, dyes, detergents, pesticides and many more.

The link between benzene and leukaemia was identified by medical experts in the 1920s. In the 1930s, workers exposed to benzene in the printing industry were known to be at risk of blood disease. In the 1940s, a study by the American Petroleum Institute warned that there is no “safe” benzene exposure level. Despite this, in the decades that followed, countless numbers of workers have been exposed to dangerous levels of benzene in the workplace.

Benzene: how people are exposed

Those at greatest risk of benzene-related diseases are workers exposed every day to benzene contained in fuels, solvents, and other products. Workers likely to have suffered prolonged exposure are those from the chemical and oil industries, printers, painters, mechanics, railway workers, rubber workers, sailors, and many others.

Most workers exposed to benzene inhale the harmful toxin. But workers can also suffer significant exposure if they spill solvents or fuels onto their hands. Benzene is particularly harmful because years can elapse between initial exposure and the onset of benzene-related blood cancer symptoms.

Benzene exposure causes a great number of health issues. When exposure is sudden and acute, it can cause drowsiness and even be fatal. But when exposure to benzene is chronic and at lower levels, it typically leads to the onset of blood disease. The two diseases that have been most closely linked to the toxic substance are acute myeloid leukaemia (AML) and myelodysplastic syndrome (MDS).

Benzene-related acute myeloid leukaemia (AML) develops in the bone marrow involved in the formation of blood cells.

Symptoms

In the early stages, symptoms are similar to flu symptoms:

Bone pain

Bleeding gums or nosebleeds

Bruising

Fatigue

Fever

Repeat infections

Pale skin and

Shortness of breath

AML progresses rapidly if not treated, so if you experience these symptoms and have been exposed to benzene, contact your doctor as soon as possible.

Diagnosis

Your doctor will perform several tests to ascertain the cause of your symptoms:

Blood tests, which will be positive for AML if more white blood cells, together with fewer red blood cells and platelets than normal are detected;

Bone marrow biopsy, by which the doctor will extract a bone marrow sample from the hip bone for testing; and Lumbar puncture, which involves the extraction of fluid from the lower back with a needle to test for leukaemia cells.

If the doctor diagnoses AML, you will probably be referred to a specialist – an oncologist, who treats cancer, or a haematologist, who treats blood disorders – who will decide the best course of treatment.

Treatment

AML treatment depends on the type of disease and its progression, as well as the patient’s age and general health. For most people, treatment consists of two phases:

Remission induction therapy. The first phase of traditional treatment aims to destroy as many tumour cells as possible. Treatment typically involves chemotherapy, although some forms of AML also respond well to a combination of chemotherapy and other anticancer drugs.

Maintenance therapy. Because remission induction therapy does not usually kill all the tumour cells, AML treatment also includes maintenance therapy (also known as consolidation, post-remission, or intensification therapy). Maintenance therapy typically involves another chemotherapy. Patients with newly diagnosed AML can also receive a stem cell or bone marrow transplant from a compatible donor or from the healthy stem cells of the patient collected during remission.

Myelodysplastic syndrome (MDS)

Myelodysplastic syndrome describes a group of bone marrow blood disorders. It causes immature or dysfunctional blood cells to form, which die before leaving the bone marrow or immediately upon entering the bloodstream.

Symptoms of MDS

Symptoms of MDS, which typically only appear in more advanced stages of the disease, include:

Excessive bleeding and/or bruising;

Fatigue;

Infections;

Pale skin;

Petechiae (small red spots on the skin, especially the legs or areas constricted by tight clothing); and

Shortness of breath

Diagnosing MDS

The tests to confirm MDS generally include some or all of the following:

Complete blood count, which ascertains the number of blood cells in a blood sample;

Peripheral blood smear, which is examined for blood cells of abnormal appearance, shape of size; and

Bone marrow biopsy, which extracts biological material from the bone marrow and a bone fragment using a fine needle inserted into the hip bone to look for abnormalities.

MDS treatment

Doctors are still working on a cure for myelodysplastic syndrome. Treatments to manage the symptoms and complications of MDS include:

Growth factor drugs. These can increase the number of red blood cells in the body, which could minimise the need for blood transfusions. Other growth factors increase the production of white blood cells, which help to prevent infection.

Drugs that stimulate cell maturation. These can help blood cells to mature, which will improve quality of life and could help delay the onset of acute myeloid leukaemia (AML).

Drugs that suppress the immune system (immunosuppressants).

Drugs that mitigate the need for drug transfusions.

Bone marrow / stem cell transplant.

This is a risky procedure for elderly patients who tend to develop MDS. It replaces dysfunctional bone marrow cells with healthy cells from a compatible donor (allogeneic transplant) or with healthy cells from the patient collected during remission (autologous transplant).

Healthy lifestyle. Patients with MDS benefit from developing habits to prevent infection, such as regularly washing their hands, washing food, and cooking it properly, and avoiding close contact with people who are sick.

This type of dispute is typically brought against the manufacturers, distributors or suppliers of any chemical and non-chemical substances that cause injury or illness.

Cases of toxic offences are often filed on behalf of people afflicted by devastating diseases caused by exposure to a hazardous substance. The related disease is often diagnosed long after exposure to the toxin. Despite the serious harm caused, long latency periods can pose a challenge in these cases.

Nevertheless, many victims and their families have the right to receive compensation for their pain and suffering because the manufacturers of these substances were often already aware of the dangers but did not inform the workers.