A GUIDE Special Bioassay for Workers and Their Families Table of Content

Introduction 1

For Workers Who’ve Been Placed on Special Bioassay 2

Why am I being asked to submit additional urine samples? 2

What is an “elevated” routine? 2

What kind of incidents might cause you to place a worker on special bioassay? 2

What do I do now that I’ve been asked to submit another sample? 3

How do you determine if an intake has happened? 3

If there has been an intake, how do you determine the dose? 4

Why do you need so many samples to determine if there’s been an intake? 5

How do you report your fndings? 6

If I need more information, what should I do? 7

For Those Who Have Had an Intake 8

If I’ve had an intake, what does that mean? 8

What is a radionuclide intake? 9

How do intakes happen? 9

If I’ve had an intake, what should I do? 10

Will I get sick because of an intake? 10

What is chelation therapy, and when is it recommended? 11

If I’ve had an intake, is it safe for me to be around my family, friends, and pets? 12

Helpful Resources 13

Glossary 14 Introduction

Los Alamos National Laboratory radio- If there has been an intake and the dose logical workers are routinely monitored is signifcant, the worker would probably for both external and internal radiation already know because the circumstances doses. To detect exposure to radiation leading to large doses tend to be imme- from external sources, workers wear diately obvious. So, while a worker might dosimeters (for example, TLD badges). be alarmed when asked to submit a large To detect intakes of radioactive materials number of urine samples, it is actually (radionuclides), radiological workers are a sign that the intake, if it happened, is placed on a routine bioassay monitoring very small. This is because large intakes protocol: regular analysis of urine samples are much easier to detect than smaller taken throughout the year. intakes, so they can usually be detected with fewer samples. If routine bioassay ofers no indication of an intake, a worker will receive an annual This booklet, prepared by the Internal report indicating that no intakes have Dosimetry team, is for workers who occurred. If, however, a routine bioassay have been placed on a special bioassay measurement indicates that an intake protocol. If you are one of those workers, may have occurred (an “elevated” routine) the booklet will help you and your family or if there has been a workplace incident understand the special bioassay process, (for example, the failure of a fume hood and it will provide information about or occurrence of a fre), a worker will be radiation and radiation exposure. placed on a special bioassay protocol, which requires the worker to submit one Please call if you have questions. or more urine samples to follow up on Internal Dosimetry Team Members the possible intake. These samples help the Laboratory’s Internal Dosimetry team Tom Waters, program lead answer the following questions: 665-2940 (uranium) • Has an intake actually happened? John Klumpp 667-0325 (plutonium and americium) • If there has been an intake, what is the Deepesh Poudel dose? 665-1798 (tritium) Luiz Bertelli 664-0292 (backup)

1 For Workers Who’ve Been Placed on Special Bioassay

Why am I being asked to submit additional urine samples? If a radionuclide intake (“intake” for short) may have occurred, we place the afected worker on a special bioassay protocol, which requires the submission of more urine samples than are usually submitted during the year (routine bioassay monitoring). We call for these additional urine samples if a routine bioassay measurement has an elevated result—an elevated What kinds of incidents might routine—or if a worker was in the vicinity cause you to place a worker on of an incident that might have caused an special bioassay? intake. In either case, we will ask for a series of urine samples over several Some incidents that would cause us to ask months because that is the only way we for special bioassay are dramatic—for can know if the worker has had an intake. example, a fre—but thankfully, such incidents are very rare. Most situations What is an “elevated” routine? that require special bioassay are such A routine bioassay that comes back things as failure of a fume hood or the higher than expected is called an elevated discovery of small amounts of material on routine bioassay, or just an elevated a worker’s skin. As with routine bioassay, routine. Most elevated routines are false special bioassay often shows that little or alarms, meaning that there has not been a no radionuclide intake has happened. radionuclide intake, but we need to collect more bioassays to be sure.

2 What do I do now that I’ve the sample as soon as possible to help been asked to submit another speed the process of determining whether sample? you had an intake. Your special bioassay kit will usually be How do you determine if an identical to the one you used for your intake has happened? routine bioassay, and it will be provided, We look for intakes by measuring the flled, and returned in exactly the same radionuclides in urine samples submitted way. Rarely, some incident-related kits for bioassay. To determine if an intake will need you to provide a larger sample. has happened, we ask for a series of urine If that is the case, someone will call you samples so we won’t be fooled by a single to explain exactly what you need to do. elevated sample (i.e., a false positive). The Collect your new urine sample following additional measurements will tell us if the instructions in the kit. Please return there really has been an intake.

Of 4,000 people tested, 20 have People with no intakes: People with intakes: had an intake. 3,980 20

Suppose the test Correct test result Incorrect test result Correct test result Incorrect test result is right 95% of for 95% of 3,980 for 5% of 3,980 for 95% of 20 for 5% of 20 the time. people people people people

Of 218 positives, Negative results: Positive results: Positive results: Negative results: 199 are 3,781 people 199 people 19 people 1 person false alarms.

Even very accurate tests can produce false alarms. The hypothetical test illustrated here is accurate 95% of the time, so it produces some false positives, which are eliminated through additional testing.

3 The vast majority of workers who are If there has been an intake, how placed on special bioassay have not had do you determine the dose? intakes. We place about 50 people a year on special bioassay, and fewer than 5 of The committed efective dose (CED), them turn out to have had intakes. which is the total radiation dose an intake will cause over 50 years, depends on the There are several reasons why an elevated amount of radioactive material in the routine might be a false alarm. All bio- body and the material’s chemical form. assay measurements detect background We can determine both the CED and the radiation from naturally occurring chemical form by analyzing multiple urine radionuclides, cosmic rays, and the sun. samples collected over several months. We always take such natural radiation into account when analyzing a urine sample, Decades of research have taught us how but sometimes there are random spikes in diferent radionuclides move between the background radiation, and an elevated diferent tissues and organs, including the routine may simply refect one of those bladder (from which radionuclides are spikes. Also, the amount of a radionuclide excreted through urine). Because we have being excreted by a given person varies this knowledge, a single urine sample, randomly from day to day. Finally, urine which tells us how much material moved samples may become contaminated from the rest of the body into the bladder during the measurement process. during the sample-collection time, allows us to estimate how much material is cur- Be prepared to wait. Testing a urine sample takes several weeks from the time you submit it, and we often need multiple samples to decide if an intake has happened. You will receive progress reports every month with information about the status of our analysis.

4 rently in the body. Additional samples tell Why do you need so many us how the amount of material moving samples to determine if there’s into the bladder is changing, which lets been an intake? us estimate when the intake happened and where the materials were deposited Every urine measurement will detect in the body. This ultimately leads to an some radiation that has nothing to do estimate of the CED. Because there are so with an intake. For example, the amount many unknown quantities, many samples of natural radiation detected in a urine are often needed for a reasonably precise measurement might be high enough to estimate. look like an intake. The only way we can know for sure if an intake has happened is Knowing when the intake occurred can by collecting more samples and seeing if also help us to determine the dose, so for we continue to detect more radiation than larger intakes, we sometimes conduct average in each sample. interviews with the afected worker. The interviews help us determine when an We also need to collect a lot of sam- intake, if it occurred at all, might possibly ples because detecting an intake is not have happened. The interviews are not to enough: we also have to determine the fgure out what might have gone wrong dose. To do that, we need to know when or to assign blame. the intake happened, how big the intake was, how soluble the material was (how quickly it is being absorbed), and other factors. We estimate all of these things using multiple urine bioassay samples. It is worth remembering that large intakes are much easier to detect than smaller intakes and can be detected with fewer samples. So, while being asked to submit multiple samples is often alarming, it is usually a sign that the intake, if it hap- pened, must be very small.

5 How do you report your All workers participating in routine fndings? bioassay monitoring receive an annual dose report, which documents their total All workers being monitored for radionu- radiation dose from the past year. This clide intakes receive annual dose reports dose includes the external dose (deter- documenting their exposure status. mined by dosimetry badges) and the Workers who have been placed on special internal dose, as expressed by the 50-year bioassay because of an elevated routine CED (see Glossary) that would be caused or an incident receive monthly progress by any radionuclide intakes. For workers reports and an ofcial dose report when whose routine bioassay comes back nega- we reach a conclusion about the intake tive for an intake, the annual dose report and dose. will show that the CED is zero. However, Following the dose assessment. At the intakes detected through routine bioassay end of the dose-assessment process, if the are often not confrmed during the same results show that an intake has happened, calendar year in which they happened. If we call the worker. Calling the worker that is the case, the dose won’t appear on gives us the opportunity to explain the the annual dose report. process, the results, and the health impli- New bioassay samples sometimes allow cations (if any) of our fndings. The worker us to update our dose estimates from also receives an ofcial dose report. intakes that happened many years ago. Depending on the size of the dose, reports When this happens, the dose estimates may be delivered by email or in person. for past years change on the annual dose When we have determined whether or report. not a worker has had an intake, we also You can fnd up-to-date dose estimates contact the worker’s managers and the for past years on the Dosimetry Reporting radiation protection team responsible for Project (DRP) website: drp.lanl.gov. the worker’s safety. A radionuclide intake may indicate that the job risk needs to be re-evaluated and/or controlled more efectively. In those cases, the Radiation Protection team determines what went wrong and how we can do better.

6 If I need more information, For information about your case or about what should I do? radionuclide intakes in general, you can call us, the Internal Dosimetry team, and Worrying about radionuclide intakes we will answer all your questions. (See can be stressful, not only for workers but contact numbers on pp. 1 and 17.) also for families. We understand that a possible intake can be a hard thing to talk For information about the medical about and that you may be worried about implications of radionuclide intakes, you frightening your loved ones. can speak to your personal physician or a physician at LANL Occupational Health. While waiting to receive your special bioassay kit, we recommend that you take Friends and family are usually the best some time to learn about radionuclide place to turn for emotional support, but intakes and the process we follow to we understand that this can be a hard determine if they have happened. thing to talk about. If you want to talk to your family but aren’t sure how, Occupa- Talk to someone. Many options are tional Health can provide you with specifc available if you want to talk to someone techniques for how to broach the subject about what you’re going through. and can tell you what to expect when you do. If you feel that you need more support than you can get from friends and family, remember that Occupational Health provides counseling free of charge.

7 For Those Who Have Had an Intake

If I’ve had an intake, what does If your dose report says that you have a that mean? CED of 500 mrem, this really means your intake will give you an average dose of This means that we have reviewed your 10 mrem per year for the next 50 years. urine measurements and found strong By comparison, the dose from natural evidence that a radionuclide intake has background radiation in Los Alamos (not happened. Your dose report includes our including medical procedures) is about best estimate of the committed efective 520 mrem per year (26,000 mrem over 50 dose (CED): the radiation dose your intake years). will cause over the next 50 years. No Immediate Health E˜ects and Likely Tissue Damage No Observable Increase in Cancer Risk and/or Radiation (rad.) Sickness Chest x-ray: 2 mrem 100,000 mrem: mild rad. sickness, Mammogram: 300 mrem cancer risk up ~5% Chest CT scan: 600 mrem Up to 600,000 mrem: moderate rad. sickness Flight, NY to Los Angeles: 2.5 mrem Los Alamos background (over 1 year): 12,500,000 mrem: prostate brachytherapy 520 mrem (over many weeks) LANL dose limit (over 1 year): 1,100,000 mrem: bone marrow 2,000 mrem transplant (over 48 hours) Regulatory dose limit (over 1 year): 5,000,000 mrem: to organ targeted by 5,000 mrem cancer therapy (over ~10 weeks) Los Alamos background (over 50 years): 26,000 mrem

Increased Cancer Risk, Lethal Doses No Radiation Sickness 600,000 mrem: fatal (30 days)— 10,000 mrem: cancer risk up ~0.55% largest dose from “one of world’s 25,000 mrem: drop in blood cells, worst radiological incidents” (IAEA): no symptoms Goiania, Brazil, 1987 66,000 mrem: Mars round trip (8 months) Up to 1,000,000 mrem: 1,000,000 mrem: largest estimated LANL severe rad. sickness (1 week) plutonium dose (over 50 years) Above 1,000,000 mrem: fatal (in days)

Shown here are chronic (delivered over time) and acute (delivered all at once) radiation expo- sures, along with their sources and efects. 8 The CED in your dose report is only an be more harmful because they tend be estimate and will probably change when delivered all at once. Whether internal or we collect more bioassay kits from you. external, doses smaller than 10,000 mrem do not measurably increase an adult’s What is a radionuclide intake? chances of getting cancer. A radionuclide intake (intake, for short) How do intakes happen? occurs when radionuclides enter a person’s body through breathing, swallowing, Most intakes at LANL happen when radio- skin contact, a wound, or an injection nuclides are inhaled. Sometimes, intakes (for example, iodine-131 for treating are detected through routine bioassay. thyroid cancer). Radiation doses caused When that happens, it can be impossible by radionuclides inside the body are called to say exactly when the intake happened, internal doses to distinguish them from so we cannot always determine what doses caused by sources outside the body, caused the intake. Other times, intakes which are called external doses. happen because of an incident, in which case we can usually say exactly what Intakes are responsible for most of the happened. radiation dose we all receive from natural background radiation—about 520 mrem It is worth remembering that while some annually in Los Alamos. Only about 15% of the radionuclides we work with do not of that is caused by external sources: exist in nature, the radiation that comes radioactive materials in the ground and from them is the same as the radiation radiation from the sun and cosmic rays. that comes out of naturally occurring The other 85% (roughly 440 mrem) is an radionuclides. For example, plutonium internal dose caused by intakes of natural is a man-made element—it does not radionuclides in food, water, and air. occur in nature. However, the kind of Because internal doses tend to be radiation released by plutonium—alpha delivered very gradually over the course particles—is the same kind of radiation of weeks, months, or even years, they are that is released by radon, which accounts much less harmful than external doses in for at least three-quarters of the natural terms of causing deterministic efects such background radiation dose. as radiation sickness. External doses can

9 If I’ve had an intake, what Will I get sick because of an should I do? intake? Our frst concern is for your well-being. The health efects of concern in relation Although the vast majority of intakes are to radiation exposure are cancer and much too small to pose a major health radiation sickness. risk, even very small intakes can cause signifcant anxiety in workers and their Cancer. Radiation doses greater than families. Here are some of the things you about 10,000 mrem may increase the risk can do if you’ve had an intake. of developing cancer. Specifcally, each 10,000 mrem increases your chances Talk to the internal dosimetrist. All of dying from cancer by about 0.55%. workers who have had intakes can talk Intakes this large have happened, but they with specialists about how their intake are very rare. was detected, what the intake means for their health, and how they can take The majority of intakes we detect result in care of themselves and their families. For committed doses of 10s or 100s of mrem. information about how the intake was In spite of a huge number of studies detected and what the dose report means, spanning more than half a century, no one you should contact the internal dosime- knows whether doses that small increase trist who was responsible for calculating the risk of cancer. The risk due to low your dose. That person’s contact informa- doses, if it exists, is so small that research tion is included with your dose report. studies involving hundreds of thousands of people have been unable to detect it. Talk to a doctor or counselor at Occu- The ofcial position of the Health Physics pational Health. To discuss the possible Society, America’s leading organization health efects of your intake, let Occu- of radiation safety professionals, is that pational Health arrange for you to speak no increase in cancer risk will ever be ob- with a physician. If you feel the need, served for doses less than 10,000 mrem. Occupational Health also has counselors, who can provide emotional support for Suppose you got a radiation dose of you and your family free of charge. 1,000 mrem. We don’t know if doses that small increase the risk of cancer, but to Occupational Health can be reached at be conservative, let’s assume they do. We 667-0660. know that the risk of fatal cancer increases

10 by 0.55% for every 10,000 mrem, so the What is chelation therapy, and 1,000 mrem dose would increase your when is it recommended? risk of cancer by 0.055%. Every American has a 20% chance of dying from cancer, Chelation therapy is the use of chelating so a radiation dose of 1,000 mrem would drugs, administered via an IV injection raise your chance of dying from cancer to or inhaler. Chelating drugs are drugs 20.055%. that combine with heavy metals inside the body and cause them to be removed Radiation sickness. Radiation sickness rapidly from the body through urine. refers to the illness that happens within a Chelation therapy is commonly used few days or weeks of getting a very large in hospitals to treat people who have radiation dose. No one at Los Alamos been poisoned by materials such as lead, National Laboratory (or any other U.S. na- arsenic, or mercury, and it can also be tional laboratory) has ever developed any used to treat people who have received a symptoms of radiation sickness because large intake of radioactive materials, such of an intake. This is because the doses as plutonium or americium. from intakes of plutonium and americium are delivered gradually over many years, When administered immediately after which is much less dangerous than doses a very large intake, chelation therapy that happen all at once. can signifcantly reduce the committed dose because it removes the radioactive If you need to see a doctor. In very rare materials from the body before they can cases, intakes are large enough to warrant attach themselves to tissues in the bones medical treatment. The circumstances and liver. However, the therapy is efective causing very large intakes are extreme only if administered soon after an intake enough that they are noticed right away, occurs. long before they would be discovered by routine testing. For example, a large Chelation therapy carries a risk of side release of radioactive materials to the efects, so it should be given only if the air would be detected by on-the-job beneft outweighs the risk. detectors, which set of alarms. The most common type of medical treatment for large intakes is chelation therapy.

11 If I’ve had an intake, is it safe for me to be around my family, friends, and pets? The radiation from uranium, plutonium, you cannot pass the radioactive materials tritium, and americium cannot penetrate inside of you to another person through your skin or leave your body: it is not con- kissing or sex. tagious. So, it is safe to shake hands with friends, cuddle with your children and If you have an intake, you will not be a pets, and sleep next to your spouse. Also, danger to anyone around you.

After an intake, some people are afraid to cuddle or share a bed with a loved one.

But being close is perfectly safe. If the radiation could escape your body, we wouldn’t need bioassay to detect it in the frst place!

So, don’t be afraid to get as close as you like. And remem- ber, kissing is safe too!

12 Helpful Resources Resources for Los Alamos Employees Google Scholar and Their Families This website is an excellent resource for fnding Employee Assistance Program free peer-reviewed literature about ionizing radiation (and many other subjects). The Laboratory’s Employee Assistance Program provides free counseling to employees and Los Alamos Science, Number 23, 1995, their families. It can help employees talk to Radiation Protection and the Human their families and friends about intakes with- Radiation Experiments out causing fear or misunderstanding. The journal Los Alamos Science was published Los Alamos Radiation Protection Website by the Laboratory from 1980 to 2006. This issue is devoted to the history of radiation safety. It This website, available on the Yellow network, is full of useful information, informative inter- provides information about the Laboratory’s views, and interesting (sometimes alarming) radiation protection philosophy and practices, history. Google “Los Alamos Science” to access and it provides links where you can access your the journal’s archives. dose history. Radiation Efects Research Foundation In Vitro Bioassay Services Website This cooperative U.S.-Japan foundation is a This website, available on the Yellow network, scientifc organization that studies the health provides information about the in vitro (urine) efects of atomic bomb radiation—the bioassay program, including how employees longest-running study of this type. Google the are enrolled in bioassay monitoring and how foundation to reach its information-packed they should fll their kits. It also provides phone website. numbers where you can ask questions about your bioassay kit. U.S. Nuclear Regulatory Commission Information about Radiation Safety The U.S. Nuclear Regulatory Commission (NRC) and Internal Dosimetry website gives information about the health efects of radiation (search for “radiation Environmental Protection Agency protection”), along with links to relevant NRC brochures and fact sheets. The Environmental Protection Agency’s website ofers information about radiation World Health Organization, “Ionizing protection and natural background radiation. Radiation, Health Efects and Protective Use the site’s Search feature. Measures” Health Physics Society The website for the World Health Organiza- tion (WHO) ofers information on ionizing The society maintains a great website with radiation. “Ionizing Radiation, Health Efects information about radiation exposure. and Protective Measures” can be found on the WHO website by clicking on Fact Sheets under Health Topics, Resources. 13 Glossary

ALARA Bioassay Measurement ALARA is an acronym for the fundamental Bioassay measurement is a type of goal of radiation safety, which is to keep measurement in which radioactive radiation doses “As Low As Reasonably materials are measured to determine their Achievable.” behavior inside a person. Measurements performed directly on a person are in vivo Annual Occupational Radiation measurements, while those performed Dosimetry Report in a test tube are in vitro measurements. Every March each employee who is being At the Laboratory, we use either urine (in monitored for radiation doses receives a vitro) or whole-body radiation counter (in report documenting the total radiation vivo) bioassay measurement to determine dose from the previous calendar year. how much radioactive material is present in the body and how quickly it is moving Background Radiation amongst the various organs and tissues. Background radiation is the radiation that Bioassay Ofce exists naturally on Earth. It comes from sources such as cosmic rays and radionu- The Bioassay Ofce is responsible for clides in the soil. The dose from back- distributing and picking up bioassay kits. ground radiation in Los Alamos is about It tracks the status of kits until the fnal 520 mrem per year. Background radiation measurement results are reported by the is separate from the radiation a worker Laboratory’s Nuclear and Radiochemistry may be exposed to in the workplace, group. You can call the Bioassay Ofce which is occupational radiation. (667-6275) at any time to ask about the status of your kit.

14 Chelation Therapy Dose Chelation therapy involves administering Dose is the amount of radiation absorbed a drug that binds itself to heavy metals, by the body. External doses are doses from such as plutonium and americium, and radiation sources outside the body, for causes them to be removed from the body example, x-ray machines. Internal doses (typically through urine). This can dra- are doses from radiation sources inside the matically reduce the radiation dose that a body, for example, radionuclide intakes. person is likely to receive as the result of The health risk from a dose depends on an intake. Chelation therapy is efective the type of radiation involved and the only if given shortly after the intake occurs particular tissue that receives the dose. and should be administered only when See Equivalent Dose and Efective Dose for the beneft outweighs the risk. more information. Committed Efective Dose (CED) Dosimeter The committed efective dose (CED) is the A dosimeter is a device that measures total efective dose an individual receives radiation dose. One type of dosimeter is a over the course of 50 years as the result of thermoluminescent dosimeter, known as a radionuclide intake. a TLD, which is generally worn as a badge. Dosimeters are used to monitor the Deterministic Efect amount of external radiation dose workers A deterministic efect of radiation receive and to let them know if radiation exposure, sometimes called a threshold levels around them have increased. efect or non-stochastic efect, is an efect Dosimetry Reporting Project that always occurs beyond a certain dose threshold but does not occur below that On the Dosimetry Reporting Project threshold. Examples include sunburns, website (DRP.lanl.gov), an employee can hair loss, and radiation sickness. Most fnd his or her up-to-date dose estimates deterministic efects are the result of cells for past years. being killed by radiation exposure. The efects usually appear within hours or days of exposure.

15 Elevated Routine Bioassay Radiation An elevated routine bioassay (or elevated Radiation is photons and particles that routine) is a routine urine sample mea- carry enough energy to ionize an atom, surement that yields a radionuclide count that is, remove electrons from around the exceeding what is expected. Although atom’s nucleus. When atoms are ionized, most elevated routines turn out to be false they try to regain their lost electron(s) alarms, they are a warning that an intake through chemical reactions. In living may have occurred. For that reason, an creatures, those reactions sometimes elevated routine triggers special bioassay. lead to chemicals that can damage cells. Technically, whenever we use the word Intake “radiation” in this book, we are talking An intake is an event in which radioac- about ionizing radiation. tive materials are taken into the body. Radionuclide Radioactive materials can enter the body through the lungs, digestive tract, skin (in A radionuclide is any atom that emits radi- the case of tritium), or wounds (such as ation when its nucleus “decays” to a lower cuts or abrasions). energy state, often transforming itself into a new kind of atom. Internal Dosimetry Routine Bioassay Internal dosimetry is the science of detect- ing intakes of radionuclides and determin- Routine bioassay involves regularly sched- ing the committed dose that is likely to uled measurements of in vitro samples result from them. (urine samples) submitted by workers whose jobs require monitoring for intakes Internal Dosimetry Team of radioactive materials. The Internal Dosimetry team is responsi- ble for monitoring Laboratory employees for intakes of radionuclides and reporting the fndings from the employees’ bioassay measurements. This booklet was devel- oped by the Internal Dosimetry team.

16 Special Bioassay Internal Dosimetry Team Members Special bioassay involves one or more Tom Waters, program lead measurements of urine samples 665-2940 (uranium) (usually submitted once a month) to determine if a worker who has had an John Klumpp elevated routine bioassay has really 667-0325 (plutonium and americium) had an intake. Investigating a possible Deepesh Poudel intake requires several special bioassays 665-1798 (tritium) and may take several months. Luiz Bertelli Stochastic Efect 664-0292 (backup) A stochastic efect, or random efect, increases the probability that some- thing will happen. The most important stochastic efect of large radiation doses is an increase in the probability that a person will develop cancer. Radia- tion-induced cancers, if they happen, can take many years to occur.

17 LA-UR-19-28425

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