Chronic Lymphocytic Leukemia and the Railroad

CLL (chronic lymphocytic Leukemia) is a form of cancer which affects both bone marrow and blood. It grows slowly and can cause a decline in blood platelets (thrombocytopenia) and swelling of lymph nodes, or an increase of the spleen and liver.

Studies have linked long-term exposure to benzene, a compound found in diesel fumes/exhaust and used by Railroad Esophageal Cancer workers on trains, to a higher risk of CLL. CLL has been linked to exposure to certain pesticides.

Benzene

The chemical benzene poses a risk to humans and can cause leukemia in those who are exposed for prolonged periods. Benzene can be found in gasoline, industrial solvents such as glue, paint and varnish. It is also used to produce other chemicals, such as aniline, phenol and dodecylbenzene which are used for dyes and degreasing of metal. Cancers of the blood and especially leukemia, are among the most serious complications resulting from the use of benzene. The toxicity of benzene can damage bone marrow, and the damage can result in chronic myeloid leukemia (CML). The disease starts in the bones, then develops into blood. It can also develop into other blood cancers, like myelodysplastic or non-Hodgkin's lymphoma.

Workers who are routinely exposed to benzene while at work are at a higher risk of developing these diseases. Researchers analyzed 15 studies in a 2010 Environmental Health study and found that workers exposed to benzene regularly at work had a 40 percentage higher risk of contracting leukemia.

Exposure to benzene is hazardous for any person, but it's particularly harmful for people who work at oil refineries, rubber factories gas stations, and shoe manufacturing facilities. Other occupations that may be affected include truck drivers, mechanics and railroad workers. Benzene is not only harmful to bone marrow, but it can also harm the skin and the eyes. It can be inhaled and taken in by workers.

Butadiene

It is beyond dispute that railroad workers are exposed many hazardous chemicals, such as butadiene and benzene every day. These chemicals are found in diesel exhaust that is emitted by trains on the tracks. Exposure to these toxic chemicals can have grave consequences for the health of railroad workers as well as their families. The presence of these substances in diesel exhaust has been associated with CLL, as well as other leukemias and cancers.

Butadiene is a synthetic chemical used to make synthetic rubber and some plastics. It is also an ingredient in fungicides and adhesives. 1,3-Butadiene is also a byproduct from petroleum processing and extraction of gas and oil. It is released into the air in industrial workplaces, as as from bush and forest fires, agricultural burning and from cigarette smoke.

Exposure to BD can cause irritation of the throat, nose and lungs. It can also cause drowsiness as well as blurred vision. Chronic exposure can lead to kidney and liver damage, as well as anemia. It is a known cancer-causing drug and has a moderate acute and slight chronic toxicity for aquatic life.

Butadiene is flammable and could evaporate quickly when released into the air. Its half-life is approximately one day in the air. It breaks down quickly when exposed to sunlight. The most popular method of human exposure to butadiene is through inhalation.

Pesticides

Many railroad employees were exposed to benzene, butadiene and pesticides on a regular basis. These chemicals are found in diesel fumes/exhaust that railroad workers breathed through their noses as well as mouths. Railroad workers also employed insecticides and herbicides on rail tracks, at railway crossings, as well as inside the rail yards to control the growth of vegetation. Some of these chemicals have been associated with cancer, such as paraquat and 2,4-D.

Other factors that increase the risk of developing chronic leukemia are age (this cancer is more prevalent in older adults) and a family background of blood and bone-marrow cancers including other types of lymphoma. A small portion of those suffering from chronic lymphocytic leukemia might change to a more aggressive form of the disease known as diffuse large B-cell lymphoma which is linked to other health issues, such as hemolytic anemia autoimmune and low platelet counts.

The National Cancer Institute (NCI) recommends that patients suffering from chronic lymphocytic cancer discuss their working history with a physician. This is particularly important if the worker was exposed to carcinogens, such as benzene or butadiene in the course of their work. This PDQ cancer summary was drafted by NCI Staff and is based upon scientific evidence from human research. This summary is intended to help patients, caregivers and their families make informed decisions regarding their care.

Genetics

The chance of being diagnosed with chronic lymphocytic leukemia is affected by a variety of factors. It is most common among older adults, specifically those in their 70s. People with an ancestor with the disease also have a higher risk. Exposure to certain chemicals like benzene may also increase the risk. People who worked in the railroad industry are at a greater risk of developing CLL as well as other blood cancers.

In some instances, the B cells that produce antibodies change and grow into cancerous cells. They then begin to grow at a higher rate than healthy cells. The cancerous cells encircle healthy ones in bone marrow and blood and may cause other health issues.

If the cancerous cell is Ig-unmutated and grows slower than Ig mutated. They can cause a variety of symptoms, depending on the extent to which they expand and the places they expand.

Anemia (low red blood cell count) as well as thrombocytopenia (low platelet count) and recurrent infections are all signs. The slow-growing version of the disease may also cause enlarged lymph nodes that can hinder the functions of nearby organs.

Researchers are studying whether a genetic factor could be linked to the risk of developing chronic leukemia. Participants in genetic research are required to supply a DNA or Railroad Esophageal Cancer saliva sample, and also their medical and family histories.