RADIONUCLIDE FACT SHEET


October 01, 2025

WHAT IS PLUTONIUM?

� Radioactive Plutonium is virtually non-existent in nature. It is made in nuclear reactors (which use uranium-238 as fuel.).

� Plutonium can be water soluble or insoluble, depending on its chemical form.

Plutonium environmental exposure pathways!

� Plutonium metal reacts and burns in the air producing deadly minute particles which can be inhaled into the lung, and it absorbs or clings to soil particles in its soluble and insoluble forms. In large amounts, plutonium will simply corrode in air like rusting iron.

� In soil, plutonium concentrates in the top 5cm of soil, but can migrate as far as 25 cm deep (NAEG, 1976:23-30).

� Inhalation is the major source of plutonium exposure. Ingestion is not considered a major source because the uptake of plutonium by plants is very low and the further uptake by humans through the gut is also very low, because it is insoluble. But it is absorbed more readily in chlorinated water and also in the first six weeks of life because the immature gut of the baby allows plutonium to be absorbed through the intestinal wall.

Plutonium-239 Health Effects!

� Plutonium is known to be the most carcinogenic or cancer producing substance on earth and it is man made.

� There is little question about the type of damage caused by exposure to plutonium; lung, bone and liver cancer and leukemia are the most frequently occurring serious results of exposure. Plutonium also lodges in the testicle where it can both damage the genes of future generations and it can induce testicular cancer. It freely crosses the placenta where like the drug thalidomide, it can damage a genetically normal embryo, to produce a deformed baby.

� Insoluble plutonium particles that can be inhaled are retained in the respiratory tract (lungs.). Lung cancer has been observed in animal tests. Plutonium travels from the lungs to the blood and lymph systems.

� Soluble plutonium enters the blood quickly and deposits on bone surfaces and in the liver. Bone and liver cancers can result, because plutonium is retained in these tissues for long periods. Workers at a DOE facility in Colorado were shown to have increased cases of brain cancer from Plutonium exposure.

� In general, plutonium has a long time lapse between exposure and when cancers are diagnosed (latency period) of about 30 years, but this can vary according to the dose received.

� Once plutonium has been inhaled, there is nothing that medical science can do to reduce the risk of lung cancer. Therefore, it would be prudent to keep away from sites of accidents where plutonium levels in the surrounding soils are much higher that average, or where it has been or will be released into the air..

WHAT IS TRITIUM?

� Tritium is a radioactive gas. It is an isotope of the gas hydrogen. Tritium is found in small amounts in nature, mostly in the upper atmosphere. But It is found in large amounts as a waste product of nuclear reactors and nuclear explosions. Tritium gas can pass through containers made of steel, aluminum, or plastic.

Tritium environmental exposure pathways!

� Since hydrogen is one of the elements that make up water (H2O), tritium becomes part of a water molecule. This is called "tritiated water."

� Most of the tritium released from nuclear explosions and nuclear reactors is in the form of tritiated water. In vapor form, this water can be dispersed rapidly.

� Tritium can travel with water vapor in the atmosphere.

� Tritium in liquid water can fall as rain and enter streams, lakes, groundwater, and oceans.

� Tritium on soil can be converted to HTO by microbes. It is taken up by plant roots and incorporated into plant tissues. It is released into the air when plants transpire or "breath" and when it is taken up by plants or animals, it enters the food chain.

Tritium Health Effects!

� Tritium (H-3, a gas) or tritiated water (HTO) can be inhaled, ingested (from air and food), or absorbed through the skin. Tritium in the form of water enters by direct ingestion of drinking water and food.

� Entering the body through skin absorption, tritium or tritiated water is first retained in the skin before entering the body. Tritiated water passes through the human body in 12 days. However, when the radionuclide unites with carbon in the human body, plants, or animals, it becomes organically bound (OBT) and can remain in the human body for 450 to 650 days. One study found traces of tritium in the body 10 years after exposure.

� Tritium is carcinogenic, mutagenic, and teratogenic.

� Tritium accumulates in blood, heart, and kidney and muscle cells. The biological half-lives of HT in different organs vary; animal studies indicate it is retained longest in muscle tissues. As tritium makes its way up the food chain it may become more concentrated.

� Diseases such as Down�s syndrome and heart disease have been associated with tritium exposure in community health studies. There are many unanswered questions about tritium concentration effects on DNA (genetic damage). A study of exposed men found that 2% of urinary tritium becomes organically bound tritium OBT or fixed in human sperm cells (Murphy, 1991).,

� High internal dosage of tritium in the body is possibly associated with leukemia, blood disorders, and testicular cancer.

WHAT IS RADIOACTIVE STRONTIUM?

� Strontium-90 is a radioactive isotope of the element strontium, a substance that is chemically much like calcium. Thus, this isotope tends to concentrate in bone, where it can induce bone cancer.

� there is no natural strontium accumulates in food by concentrating thousands of times from the original levels in the soil. Levels of strontium in soil and food vary geographically.

� Strontium resembles and acts like calcium. It mostly accumulates in the human body as "strontium bone salts." In our bones and teeth, there is now about 300-350 milligrams of this mineral which was produced by atmospheric weapons testing in the 50s and 60s,.

Strontium Health effects!

� Radioactive strontium is biologically retained in human bones. Chemically, it resembles calcium (or natural non radioactive strontium) and the human body does not distinguish between the two.

� Cancer of the bone and leukemia (cancer of the white blood cells) have been observed in exposed animals. Leukemia was caused more readily by continuous low doses than by a single high dose. High doses caused disproportionately more bone cancers than low doses. There is also evidence for a weakening of the immune system.

� The major health hazard associated with ingestion of radioactive strontium is bone cancer, although leukemia and other bone related cancers resulting from irradiation of the bone marrow can also be induced.

WHAT IS RADIOACTIVE CESIUM?

Cesium-137 is a radioactive isotope of the element cesium that is produced in nuclear power plants and from the explosion of nuclear weapons.

Cesium environmental exposure pathways!

� The major pathway of human exposure to radioactive released from weapons testing and nuclear reactors is a deposition from the atmosphere to the soil, bioconcentration or uptake by grains, grass and other foods, and also subsequent concentration in grazing animals in their muscles ( meat).

� Consumption of milk, meat, and grains account for most of the human exposure, while fruits and vegetables, and fish are relatively less important sources.

Cesium health effects!

� The most likely cause of death from acute exposure to high levels of cesium-137 is destruction of bone marrow. This situation would occur after a meltdown in a nuclear power plant, or a research reactor.

� High doses of injected cesium results in death from bone marrow destruction, much like high doses of X-rays.

� Lower doses of cesium cause cancer in animals and humans. Cesium-137 can cause liver cancer in animals.

THE DANGERS ASSOCIATED WITH PLUTONIUM AND URANIUM

Over the past fifty years, the production of plutonium and highly enriched uranium (HEU) for nuclear weapons has caused enormous environmental damage and posed risks to the health of workers and communities. Plutonium and HEU are located at many sites throughout the United States, some of which are significantly contaminated. The Department of Energy recently estimated that cleaning up the U.S. nuclear weapons production complex will cost $200 billion to $500 billion and will take up to seventy-five years.

The dangers posed by plutonium and HEU are three-fold: they can be used to make nuclear weapons, they are radioactive and toxic, and their production processes involve other hazardous substances.

The Health and Environmental Dangers of the Materials

Outside the body, plutonium and uranium pose minimal risks to human health unless exposure is on a sustained basis. This is because the main type of radiation from both materials, alpha radiation, is very short-range and is stopped by the outer dead layer of skin. However, if plutonium or uranium gets into the body, the high-energy alpha radiation can damage cells and cause cell mutations that can lead to cancer. The main health concern for plutonium is inhalation of small particles or absorption through cuts or wounds. While the amount of data is limited, animal studies suggest that as little as one millionth of a gram or less of plutonium lodged in the lung is highly likely to cause cancer.

Like plutonium, uranium is a health hazard when small particles are inhaled or absorbed through wounds. But uranium is also more easily absorbed than plutonium though the gastrointestinal tract. Animal studies suggest that uranium- like plutonium, may damage reproductive organs, may harm a developing fetus, and may increase the risk of leukemia and soft tissue cancers. Uranium is far less radioactive and therefore less carcinogenic than plutonium, and uranium can cause acute damage to the kidneys by heavy metal poisoning well before radiation effects are manifest.

Under certain conditions, the accumulation of plutonium or HEU (such as in ventilation ducts or in solutions) can lead to a criticality, a chain reaction of fissioning atoms. The energy release from a criticality can be high enough to cause threats to worker safety and damage the container holding the

materials.

The Health and Environmental Effects of Obtaining Plutonium

Plutonium must be chemically separated from spent nuclear fuel in order to get it into a form usable for nuclear weapons or nuclear reactor fuel. This process, called reprocessing, produces highly radioactive liquid wastes as well as huge volumes of low-level radioactive waste.

The Department of Energy estimates that a little over half of the costs of cleaning up the nuclear weapons production complex will be due to reprocessing -- more than all other steps in the weapons production process combined.

After reprocessing and chemical dilution, the liquid wastes are hundreds of times more radioactive than the separated plutonium, and safely storing these wastes is a difficult and expensive task.

In the U.S., one hundred million gallons of high-level reprocessing waste are being stored in large holding tanks at Savannah River Site, South Carolina, and Hanford Site, Washington.

Over the past fifty years, 800 billion liters of low-level radioactive waste have also been discharged directly into the ground at Hanford.

Plutonium has contaminated inhabited areas near reprocessing sites and plutonium handling facilities in the U.S. It has migrated into groundwater at Savannah River and at Hanford.

Little is known definitively about the impact of weapons production and resulting contamination on the health of workers and surrounding communities, though numerous health studies have been undertaken. This is due partly to faulty radiation dose record-keeping, secrecy, a focus on deaths rather than disease, the lack of long-term follow-up, and the difficulties of drawing conclusions from

a relatively small number of subjects.

An independent evaluation of radiation doses to workers at the Fernald uranium processing facility showed that workers in the 1950s and 1960s were exposed beyond the allowed limit, contrary to assurances provided to the workers by the Department of Energy.

The Health and Environmental Effects of Producing HEU

One of the most serious health hazards associated with producing HEU is uranium mining. A study of uranium miners conducted by the U.S. Public Health Service between 1948 and 1982 showed significant excesses of respiratory cancers; by 1978, white underground miners in the study suffered

five times the expected rate of such cancers. The cancer risk from uranium mining is mainly due to exposure to the decay products of radon, which is itself a decay product of uranium-238.

Uranium used to produce HEU for U.S. nuclear warheads was mined before the mid-1960s. Mines operating since then have produced uranium for commercial purposes and to a lesser extent for the reactors that propel some naval vessels.

Most uranium mines in the U.S. have been shut down, but the radioactive wastes from uranium processing still pose a health risk to segments of the U.S. population. These wastes, called mill tailings, contain long-lived radioactive isotopes. As of the late 1980s, some 220 million metric tons of mill tailings had accumulated from uranium production for nuclear weapons and nuclear power.

According to the Environmental Protection Agency, groundwater has become contaminated at virtually all mill tailings sites.

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