They call those areas “cancer clusters,” and they’re hotspots where the occurrence of a greater than expected number of cancer cases among localized groups of people pop up during a specific time period.
Researchers take note when residents report several family members, friends, neighbors or coworkers being diagnosed with the same (or related) types of cancers.
Experts say cancer clusters are spots where scientists can readily identify cancer-causing substances in the environment.
More than half a million Americans will die from cancer this year, and it’s the second most common cause of death in the United States. Cancer accounts for one in every four deaths in this country, and scientists have identified geographical areas where cases – and types – of cancers are statistically anomalous.
Back in the early 1970s, a cluster of cases of rare angiosarcoma of the liver was detected among workers at a chemical plant, and an investigation revealed that workers had been regularly exposed to an industrial chemical, vinyl chloride, which led to increased rates of angiosarcoma of the liver. The chemical is now known to be a risk factor for this rare cancer.
While many suspected cancer clusters can turn out to be nothing more than random occurrences, identifying them is often key to environmental cleanup efforts.
Health departments and state cancer registries are repositories for up-to-date data on cancer incidence in a given area, and state health departments may use that data to request assistance from federal agencies like the Centers for Disease Control and Prevention (CDC) and the Agency for Toxic Substances and Disease Registry (ATSDR) should such action seem necessary.
Using long-standing tools to establish criteria to investigate reports of cancer clusters, the Centers for Disease Control and the Council of State and Territorial Epidemiologists have updated data and guidelines for investigating suspected cancer clusters and responding to community concerns.
1. ETHANOL and PLANTS
Alcohol: This one may be a no-brainer, but heavy consumption of alcohol is related to cancers in the mouth, pharynx, larynx and esophagus — in addition to liver and breast cancer. Known contaminates that are absorbed during the production of alcoholic beverages include acetaldehyde, nitrosamines, aflatoxins, urethane, asbestos and arsenic compounds.
Tobacco: Tobacco tops all categories of the single most lethal carcinogen worldwide. Chronic tobacco use can be responsible for cancers in the lungs, larynx, mouth, esophagus, bladder, kidney, throat, stomach, pancreas and cervix. There’s also an increased risk of developing leukemia. Cigarettes, cigars and pipe tobacco contain 60 compounds that are carcinogenic to humans, according to the American Cancer Society (ACS). Smoking is the leading cause of lung cancer in the United States. People who breathe second-hand smoke can be affected as well.
2. MOLD and FUNGAL TOXINS
Aflatoxin: We come into contact with aflatoxin, which is known to cause liver cancer, primarily through eating contaminated food. This carcinogen produces a fungus that thrives on corn, grains, peanuts, tree nuts and cottonseed meal. Cottonseed meal is often fed to farm animals.
Benzene: Exposure to benzene can put you at risk for leukemia. You can be exposed to it by something as simple as driving in congested traffic — or pumping gas. The Texas Transportation Institute reported that Los Angeles, New York, Chicago and Atlanta were cities with the highest amount of traffic congestion in 2007.
“People are at risk for exposure to benzene when waiting in traffic,” says Vivi Abrams, spokesperson for the Centers for Disease Control’s National Center for Environmental Health. “As far as what levels they are exposed to, that’s something that more research needs to be done about. The seriousness would depend on the amount, the root cause, the length of the exposure in the air, the levels in the air at that time and the person’s pre-existing health conditions.”
Manufacturing facilities also expose you to benzene and traces of this carcinogen are found in fruits, vegetables, nuts, dairy products, eggs and fish. But the most common exposure to benzene is through cigarette smoke, says Abrams.
In 2006, the U.S. Food and Drug Administration analyzed more than 100 soft drinks to determine the level of benzene found in those products, they learned that eight of the beverages tested contained levels of benzene that exceeded the federal standard for tap and bottled water of five parts per billion (ppb). Some of the soft drinks that were found to have the highest benzene count included Safeway Select Diet Orange, Crush Pineapple, AquaCal Strawberry flavored water, and Crystal Light Sunrise Classic Orange. The FDA asked manufacturers with the highest levels to reformulate its products in order to reduce the benzene count.
Arsenic: Exposure to arsenic is linked to an assortment of cancers, including skin, lung, digestive tract, liver, bladder and kidney. This carcinogen can appear in our food and drinking water. Seafood, rice, rice cereal, mushrooms and poultry contain the highest levels of arsenic.
Drinking water can be contaminated with pesticides that contain arsenic. This can come from natural mineral deposits of inorganic arsenic or from chemical plants that haven’t properly disposed of the compound.
Arsenic is used to pigment paint and can be contracted through the hands, fingernails, cups, cigarette smoking or by holding paintbrushes in the mouth.
5. FIBROUS MINERALS
Asbestos: Exposure to asbestos has been linked to lung cancer and mesothelioma. It has been detected in air, soil, drinking water, food, medicines and vehicle break linings.
Silica, crystalline: Linked to lung cancer, silica is a common air contaminant. People who live near sand and gravel operations are at the most risk. People are also exposed to silica via abrasives, sand paper, detergent, cement and grouts.
6. HEAVY METALS
Beryllium: Linked to lung cancer, beryllium can be contracted by inhaling dust or fumes or ingested with water and food. It is also found in fruit and fruit juices, primarily pineapple and papaya juice.
Certain occupations can expose you to this carcinogen: alloy makers, ceramics workers, missile technicians, nuclear reactor workers, electronic-equipment workers and jewelers.
Cadmium: Linked to lung and prostate cancer, cadmium can be found in grain cereal, potatoes and vegetables. Exposure also occurs through drinking water or ambient air.
Nickel: Yes, the metallic 5-cent coin is a human carcinogenic. Exposure can result in an elevated risk of lung cancer and cause epithelial and connective tissue tumors. It can also bind ionically to cells, including DNA.
Nickel is found in the air, water, food and consumer products. The general population is also exposed to nickel through nickel alloys and nickel-plated materials such as coins, steel and jewelry. It is also found in soaps, fats and oils.
Estrogens, steroidal: Estrogen is linked to uterine and breast cancer. Estrogen is found in palm kernel oil, meat, milk products and contraceptives. It is also contained in some moisturizing lotions, wrinkle-smoothing creams, hair conditioners, shampoos and other grooming products.
Ultraviolet Radiation (UVR): Typically derived from the sun, UVR radiation exposure is responsible for 90 percent of all skin cancers. Tanning beds have also been accused of heightening cancer risk.
“After reviewing 20 epidemiological studies, the International Agency for Research on Cancer reaffirmed that solar radiation is carcinogenic to humans,” said Dr. Fatiha El Ghissassi, one of the authors of A Review of Human Carcinogens, a special report conducted by the International Agency for Research on Cancer in Lyon, France. “We have moved up UV tanning beds to the highest cancer risk category Group I. The risk of skin cancer is increased by 75 percent when use of tanning beds starts before age 30.”
Ionizing radiation: CT Scans, X-rays, and nuclear radiation all have a damaging effect on DNA.
Radon: Radon is a colorless, odorless gas that is a naturally occurring element in the environment, but it is also deadly. Exposure to radon has been linked to lung cancer in several epidemiological studies. The U.S. Environmental Protection Agency found that one in 15 homes have elevated radon levels in the United States. This gas can also be found in groundwater, soil or building materials. There have also been significant levels of radon found in tunnels, power stations, caves, public baths and spas. It is the second leading cause of lung cancer in the United States, according to the American Lung Association.
Since radon gas is so prevalent, you may wonder if your home insurance rates will increase if your home has elevated levels of radon. Holly Anderson, a spokesperson for State Farm, says it’s not a factor.
“We don’t ask about radon in the underwriting process, so it’s unlikely that it will affect a homeowners policy or its eligibility,” said Anderson.
Underwriters use a number of tools to determine the cost of life insurance, but according to Kim McKeown, spokesperson for the Society of Actuaries (SOA), group insurers may look at overall mortality by geographical region, but it’s unlikely that they will single out incidents of cancer-based on environmental factors.
“Individual life insurance applicants with cancer are underwritten on an individual by individual basis,” says McKeown. “Life underwriters are not allowed to price individual life premiums based on cancer clusters.”Life insurance companies look at a number of medical conditions and other factors when they price life insurance applications. According to McKeown, someone living in a known cancer cluster cannot be excluded from getting life insurance or be charged more for a policy.
The American Cancer Society reports that there are at least 100 suspected cancer clusters in the United States. The National Cancer Institute loosely defines a cancer cluster as an abnormally high number of cancers diagnosed in a small geographic area over a period of time. Those clusters often produce rare cancers or occur in people who generally shouldn’t be subject to cancer — like children.
Oroville, Calif. – Between 2004 and 2006, there were 34 cases of pancreatic cancer in this small city in Northern California. It was determined that a wood treatment facility that pressure treated wood with pentachlorophenol (PCP) had a history of contaminating the ground water. The plant burned down in the late 1980s. Source: California Department of Health, March 2009, Pancreatic Cancer Follow-up Investigation Report.
Palm Beach, Fla. – Residents of the Acreage subdivision voiced concerns over a possible brain cancer cluster (1997 to present) in their neighborhood. To date, 104 cases of brain cancer have been submitted to the Florida Department of Health. Of those, 90 have been verified. The New York-based law firm Weitz & Luxenberg, (Erin Brockovich is a consultant at this law firm) met with residents this year to discuss their concerns. The Florida Department of Environmental Protection (DEP) is investigating. Source: Florida Department of Health, Palm Beach County Health Department.
Clyde, Ohio (Sandusky County and Surrounding areas)— From 1996 to 2006, there were 277 cases of childhood cancer in Lucas, Wood, Ottawa, Sandusky, Seneca, Wyandot, Erie and Huron counties. The case is still under investigation. Source: Ohio Environmental Protection Agency.