PUBLIC HEALTH STATEMENT 

 Strontium CAS#: 7440-24-6 

Division of Toxicology April 2004 

__________________________________________________________________________________________

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 

This Public Health Statement is the summary 

chapter from the Toxicological Profile for 

strontium. It is one in a series of Public Health 

Statements about hazardous substances and their 

health effects. A shorter version, the ToxFAQsTM, is 

also available. This information is important 

because this substance may harm you. The effects 

of exposure to any hazardous substance depend on 

the dose, the duration, how you are exposed, 

personal traits and habits, and whether other 

chemicals are present. For more information, call 

the ATSDR Information Center at 1-888-422-8737. 

_____________________________________ 

This public health statement tells you about 

strontium and the effects of exposure. 

The Environmental Protection Agency (EPA) 

identifies the most serious hazardous waste sites in 

the nation. These sites make up the National 

Priorities List (NPL) and are the sites targeted for 

long-term federal cleanup activities. Strontium and 

strontium-90 have been found in at least 102 and 12 

of the 1,636 current or former NPL sites, 

respectively. However, the total number of NPL 

sites evaluated for strontium and strontium-90 are 

not known. As more sites are evaluated, the sites at 

which strontium and strontium-90 are found may 

increase. This information is important because 

exposure to strontium and strontium-90 may harm 

you and because these sites may be sources of 

exposure. 

When a substance is released from a large area, 

such as an industrial plant, or from a container, such 

as a drum or bottle, it enters the environment. This 

release does not always lead to exposure. You are 

exposed to a substance only when you come in 

contact with it. You may be exposed by breathing, 

eating, or drinking the substance, or by skin contact. 

External exposure to radiation may occur from 

natural or man-made sources. Naturally occurring 

sources of radiation are cosmic radiation from space 

or radioactive materials in soil or building materials. 

Man-made sources of radioactive materials are 

found in consumer products, industrial equipment, 

atom bomb fallout, and to a smaller extent from 

hospital waste and nuclear reactors. 

If you are exposed to strontium, many factors 

determine whether you’ll be harmed. These factors 

include the dose (how much), the duration (how 

long), and how you come in contact with it. You 

must also consider the other chemicals you’re 

exposed to and your age, sex, diet, family traits, 

lifestyle, and state of health. 

1.1 WHAT IS STRONTIUM? 

Strontium is a natural and commonly occurring 

element. Strontium can exist in two oxidation 

states: 0 and +2. Under normal environmental 

conditions, only the +2 oxidation state is stable 

enough to be important. Pure strontium is a hard, 

white-colored metal, but this form is not found in 

the environment. Rather, strontium is usually found 

in nature in the form of minerals. Strontium can 

form a variety of compounds. Strontium 

compounds do not have any particular smell. There 

are two types of strontium compounds, those that 

dissolve in water and those that do not. Natural 

strontium is not radioactive and exists in four stable 

types (or isotopes), each of which can be written as 

84Sr, 86Sr, 87Sr, and 88Sr, and read as strontium 

eighty-four, strontium eighty-six, etc. All four 

isotopes behave the same chemically, so any 

combination of the four would have the same 

chemical effect on your body. 
 PUBLIC HEALTH STATEMENT 

 Strontium CAS#: 7440-24-6 

Division of Toxicology April 2004 

__________________________________________________________________________________________

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 

Rocks, soil, dust, coal, oil, surface and underground 

water, air, plants, and animals all contain varying 

amounts of strontium. Typical concentrations in 

most materials are a few parts per million (ppm). 

Strontium ore is found in nature as the minerals 

celestite (SrSO4) and strontianite (SrCO3). After the 

strontium is extracted from strontium ore, it is 

concentrated into strontium carbonate or other 

chemical forms by a series of chemical processes. 

Strontium compounds, such as strontium carbonate, 

are used in making ceramics and glass products, 

pyrotechnics, paint pigments, fluorescent lights, 

medicines, and other products. 

Strontium can also exist as radioactive isotopes. 

90Sr, or strontium ninety, is the most hazardous of 

the radioactive isotopes of the chemical element 

strontium. 90Sr is formed in nuclear reactors or 

during the explosion of nuclear weapons. Each 

radioactive element, including strontium, constantly 

gives off radiation, and this process changes it into 

an isotope of another element or a different isotope 

of the same element. This process is called 

radioactive decay. 90Sr gives off beta particles 

(sometimes referred to as beta radiation) and turns 

into yttrium ninety (90Y); 90Y is also radioactive and 

gives off radiation to form zirconium ninety (90Zr), 

which is a stable isotope. The radioactive half-life 

is the time that it takes for half of a radioactive 

strontium isotope to give off its radiation and 

change into a different element. 90Sr has a half-life 

of 29 years. 

90Sr has limited use and is considered a waste 

product. The radioactive isotope 89Sr is used as a 

cancer therapeutic to alleviate bone pain. 85Sr has 

also been used in medical applications. . 

Quantities of radioactive strontium, as well as other 

radioactive elements, are measured in units of mass 

(grams) or radioactivity (curies or becquerels). 

Both the curie (Ci) and the becquerel (Bq) tell us 

how much a radioactive material decays every 

second. The becquerel is a new international unit 

known as the SI unit, and the curie is an older unit; 

both are used currently. A becquerel is the amount 

of radioactive material in which 1 atom transforms 

every second. One curie is the amount of 

radioactive material in which 37 billion atoms 

transform every second; this is approximately the 

radioactivity of 1 gram of radium. 

1.2 WHAT HAPPENS TO STRONTIUM 

WHEN IT ENTERS THE 

ENVIRONMENT? 

Stable and radioactive strontium compounds in the 

air are present as dust. Emissions from burning coal 

and oil increase stable strontium levels in air. The 

average amount of strontium that has been 

measured in air from different parts of the United 

States is 20 nanograms per cubic meter (a nanogram 

is a trillion times smaller than a gram). Most of the 

strontium in air is in the form of stable strontium. 

Very small dust particles of stable and radioactive 

strontium in the air fall out of the air onto surface 

water, plant surfaces, and soil either by themselves 

or when rain or snow falls. These particles of 

strontium eventually end up back in the soil or in 

the bottoms of lakes, rivers, and ponds, where they 

stay and mix with stable and radioactive strontium 

that is already there. 

In water, most forms of stable and radioactive 

strontium are dissolved. Stable strontium that is 

dissolved in water comes from strontium in rocks 

and soil that water runs over and through. Only a 

very small part of the strontium found in water is 

from the settling of strontium dust out of the air. 
 PUBLIC HEALTH STATEMENT 

 Strontium CAS#: 7440-24-6 

Division of Toxicology April 2004 

__________________________________________________________________________________________

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 

Some strontium is suspended in water. Typically, 

the amount of strontium that has been measured in 

drinking water in different parts of the United States 

by the EPA is less than 1 milligram for every liter 

of water (1 mg/L). 90Sr in water comes primarily 

from the settling of 90Sr dust out of the air. Some 

90Sr is suspended in water. In general, the amount 

of 90Sr that has been measured in drinking water in 

different parts of the United States by EPA is less 

than one-tenth of a picocurie for every liter of water 

(0.1 pCi/L or 0.004 Bq/L). 

Strontium is found naturally in soil in amounts that 

vary over a wide range, but the typical 

concentration is 0.2 milligrams per kilogram (kg) of 

soil (or 0.2 mg/kg). The disposal of coal ash, 

incinerator ash, and industrial wastes may increase 

the concentration of strontium in soil. Generally, 

the amount of 90Sr in soil is very small and is only a 

fraction of the total concentration of strontium in 

soil. Higher concentrations of 90Sr in soil may be 

found near hazardous waste sites, radioactive waste 

sites, and Department of Energy facilities located 

around the United States. A major portion of stable 

and radioactive strontium in soil dissolves in water, 

so it is likely to move deeper into the ground and 

enter groundwater. However, strontium compounds 

may stay in the soil for years without moving 

downward into groundwater. In the environment, 

chemical reactions can change the water-soluble 

stable and radioactive strontium compounds into 

insoluble forms. In some cases, water-insoluble 

strontium compounds can change to soluble forms. 

1.3 HOW MIGHT I BE EXPOSED TO 

STRONTIUM? 

Strontium is found nearly everywhere in small 

amounts, and you can be exposed to low levels of 

strontium by breathing air, eating food, drinking 

water, or accidentally eating soil or dust that 

contains strontium. Food and drinking water are the 

largest sources of exposure to strontium. Because 

of the nature of strontium, some of it gets into fish, 

vegetables, and livestock. Grain, leafy vegetables, 

and dairy products contribute the greatest 

percentage of dietary strontium to humans. The 

concentration of strontium in leafy vegetables, such 

as cabbage, grown in the United States is less than 

64 mg in a kg of the fresh vegetables (i.e., 64 ppm). 

For most people, the intake of strontium will be 

moderate. 

90Sr is found nearly everywhere in small amounts 

from past nuclear accidents and fallout from nuclear 

explosions. You can be exposed to low levels of 

90Sr by eating food, drinking water, or accidentally 

eating soil or dust that contains 90Sr. Food and 

drinking water are the largest sources of exposure to 

90Sr. Because of the nature of 90Sr, some of it gets 

into fish, vegetables, and livestock. Grain, leafy 

vegetables, and dairy products contribute the 

greatest percentage of dietary 90Sr to humans. The 

concentration of 90Sr in fresh vegetables grown in 

the United States is less than 9 pCi (or 0.3 Bq) in 

1 kg of dried vegetables (in a hot oven). The intake 

of radioactive strontium for most people will be 

small. You can take in more 90Sr if you eat food 

that was grown on a radioactive strontiumcontaminated hazardous waste site. 

1.4 HOW CAN STRONTIUM ENTER AND 

LEAVE MY BODY? 

Both stable strontium and radioactive strontium 

enter and leave the body in the same way. 

If a person breathes in vapors or dust containing a 

chemical form of strontium that is soluble in water, 
 PUBLIC HEALTH STATEMENT 

 Strontium CAS#: 7440-24-6 

Division of Toxicology April 2004 

__________________________________________________________________________________________

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 

then the chemical will dissolve in the moist surface 

inside the lungs and strontium will enter the 

bloodstream relatively quickly. If the chemical 

form of strontium does not dissolve in water easily, 

then particles may remain in the lung for a time. 

When you eat food or drink water that contains 

strontium, only a small portion leaves the intestines 

and enters the bloodstream. Studies in animals 

suggest that infants may absorb more strontium 

from the intestines than adults. If a fluid mixture of 

a strontium salt is placed on the skin, the strontium 

will pass through the skin very slowly and then 

enter the bloodstream. If the skin has scratches or 

cuts, strontium will pass through the skin much 

more quickly. 

Once strontium enters the bloodstream, it is 

distributed throughout the body, where it can enter 

and leave cells quite easily. In the body, strontium 

behaves very much like calcium. A large portion of 

the strontium will accumulate in bone. In adults, 

strontium mostly attaches to the surfaces of bones. 

In children, whose bones are still growing, 

strontium may be used by the body to create the 

hard bone mineral itself. As a result the strontium 

will be stored in the bone for a long time (years). 

Because of the way bone grows, strontium will be 

locally dissolved from bone and recirculate through 

the bloodstream, where it may be reused by 

growing bone, or be eliminated. This process 

accounts for the slow removal of strontium from the 

body. 

Strontium is eliminated from the body through 

urine, feces, and sweat. Elimination through urine 

may occur over long periods, when small amounts 

of strontium are released from bone and do not get 

recaptured by bone. When strontium is taken in by 

mouth, the portion that does not pass through the 

intestinal wall to enter the bloodstream is eliminated 

through feces during the first day or so after 

exposure. 

1.5 HOW CAN STRONTIUM AFFECT MY 

HEALTH? 

To protect the public from the harmful effects of 

toxic chemicals and to find ways to treat people 

who have been harmed, scientists use many tests. 

One way to see if a chemical will hurt people is to 

learn how the chemical is absorbed, used, and 

released by the body. In the case of a radioactive 

chemical, it is also important to gather information 

concerning the radiation dose and dose rate to the 

body. For some chemicals, animal testing may be 

necessary. Animal testing may also be used to 

identify health effects such as cancer or birth 

defects. Without laboratory animals, scientists 

would lose a basic method to get information 

needed to make wise decisions to protect public 

health. Scientists have the responsibility to treat 

research animals with care and compassion. Laws 

today protect the welfare of research animals, and 

scientists must comply with strict animal care 

guidelines. 

There are no harmful effects of stable strontium in 

humans at the levels typically found in the 

environment. The only chemical form of stable 

strontium that is very harmful by inhalation is 

strontium chromate, but this is because of toxic 

chromium and not strontium itself. Problems with 

bone growth may occur in children eating or 

drinking unusually high levels of strontium, 

especially if the diet is low in calcium and protein. 

Ordinary strontium salts are not harmful when 

inhaled or placed on the skin. 
 PUBLIC HEALTH STATEMENT 

 Strontium CAS#: 7440-24-6 

Division of Toxicology April 2004 

__________________________________________________________________________________________

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 

Animal studies showed that eating or drinking very 

large amounts of stable strontium can be lethal, but 

the public is not likely to encounter such high levels 

of strontium. In these unusually high amounts, so 

much strontium was taken into bone instead of 

calcium that growing bones were weakened. 

Strontium had more severe effects on bone growth 

in young animals than in adults. 

It is not known whether stable strontium affects 

reproduction in people. The effect of stable 

strontium on reproduction in animals is not known. 

The Department of Health and Human Services has 

determined that strontium chromate is expected to 

be a carcinogen, but this is because of chromium. 

There is no information that any other form of 

stable strontium causes cancer in humans or 

animals. 

The harmful effects of radioactive strontium are 

caused by the high energy effects of radiation. 

Since radioactive strontium is taken up into bone, 

bone itself and the soft tissues nearby may be 

damaged by radiation released over time. Because 

bone marrow is the essential source of blood cells, 

blood cell counts may be reduced if the dose is too 

high. This has been seen in humans who received 

injections of radioactive strontium (89Sr) to destroy 

cancer tissue that had spread to the bone marrow. 

Lowered blood cell counts were also seen in 

animals that breathed or swallowed radioactive 

strontium. Numerous problems occur when the 

number of blood cells is too low. A loss of red 

blood cells, anemia, prevents the body from getting 

sufficient oxygen, resulting in tiredness. A loss of 

platelets may prevent the blood from clotting 

properly, and may result in abnormal bleeding, 

especially in the intestines. A loss in white blood 

cells harms the body’s ability to fight infectious 

disease. 

Radiation damage may also occur from exposure to 

the skin. Medically, radioactive strontium probes 

have been used intentionally to destroy unwanted 

tissue on the surface of the eye or skin. The eye 

tissues sometimes become inflamed or abnormally 

thin after a long time. Thinning of the lower layer 

of the skin (dermis) has also been reported in 

animal studies as a delayed effect. 

It is not known whether exposure to radioactive 

strontium would affect human reproduction. 

Harmful effects on animal reproduction occurred at 

doses that were more than a million times higher 

than typical exposure levels for the general 

population. 

Radioactive strontium may cause cancer as a result 

of damage to the genetic material (DNA) in cells. 

An increase in leukemia over time was reported in 

individuals in one foreign population who 

swallowed relatively large amounts of 90Sr (and 

other radioactive materials) in river water 

contaminated by a nuclear weapons plant. Cancers 

of the bone, nose, and lung (in the case of a 

breathing exposure), and leukemia were reported in 

animal studies. In addition, skin and bone cancer 

were reported in animals that received radiation at 

high doses to the skin. The International Agency 

for Research on Cancer (IARC) has determined that 

radioactive strontium is carcinogenic to humans, 

because it is deposited inside the body and emits 

beta radiation. The EPA has determined that 

radioactive strontium is a human carcinogen. 
 PUBLIC HEALTH STATEMENT 

 Strontium CAS#: 7440-24-6 

Division of Toxicology April 2004 

__________________________________________________________________________________________

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 

1.6 HOW CAN STRONTIUM AFFECT 

CHILDREN? 

This section discusses potential health effects from 

exposures during the period from conception to 

maturity at 18 years of age in humans. 

Children are exposed to stable strontium in the same 

manner as adults: usually in small amounts in 

drinking water and food. Young children who have 

more hand-to-mouth activity or who eat soil may 

accidentally eat more strontium. Infants and 

children with active bone growth absorb more 

strontium from the gut than adults. 

Excess stable strontium causes problems with 

growing bone. For this reason, children are more 

susceptible to the effects of stable strontium than 

adults who have mature bone. Children who eat or 

drink unusually high levels of stable strontium may 

have problems with bone growth, but only if the 

diet is low in calcium and protein. Children who 

drink milk, especially milk fortified with vitamin D, 

are not likely to have bone problems from exposure 

to excess stable strontium. The amount of stable 

strontium that is usually taken in from food or water 

or by breathing is too low to cause bone problems in 

children. No developmental studies in humans or 

animals examined the effect on the fetus when the 

mother takes in excess strontium. However, no 

problems are expected with fetal bone growth 

because only small amounts of strontium are 

transferred from the mother across the placenta to 

the fetus. Evidence suggests that stable strontium 

can be transferred from the mother to nursing 

infants through breast milk, but the presence of 

calcium and protein in milk protects against bone 

problems during nursing. 

Children take in, use, and get rid of radioactive 

strontium in the same ways as stable strontium. 

Children are likely to be more vulnerable than 

adults to the effects of radioactive strontium 

because relatively more goes into bone when it is 

growing. Also, children are potentially more 

vulnerable than adults to radiation damage because 

they keep radioactive strontium in bone for a longer 

time. 

Children would be expected to have the same types 

of effects from exposure to radioactive strontium as 

exposed adults. Children can be exposed to 

radioactive strontium at levels higher than 

background without showing increases in cancer 

rates. Evidence from one foreign population 

showed that children who drank water containing 

unusually high levels of radioactive strontium for 7 

years showed an increase in leukemia. High levels 

of radioactive strontium cause more bone damage 

and higher bone cancer rates when animals are 

exposed before birth or as juveniles rather than as 

adults. In humans and animals, radioactive 

strontium can be transferred into milk or across the 

placenta into the fetus. 

1.7 HOW CAN FAMILIES REDUCE THE 

RISK OF EXPOSURE TO 

STRONTIUM? 

If your doctor finds that you have been exposed to 

significant amounts of strontium, ask whether your 

children might also be exposed. Your doctor might 

need to ask your state health department to 

investigate. Public health officials may publish 

guidelines for reducing exposure to strontium when 

necessary. 
 PUBLIC HEALTH STATEMENT 

 Strontium CAS#: 7440-24-6 

Division of Toxicology April 2004 

__________________________________________________________________________________________

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 

It is possible that higher-than-normal levels of 

stable strontium may occur naturally in soil in some 

places or that higher levels of radioactive strontium 

may be found in soil near hazardous waste sites. 

Some children eat a lot of dirt. You should prevent 

your children from eating dirt. Make sure they 

wash their hands frequently, and before eating. If 

you live near a hazardous waste site, discourage 

your children from putting their hands in their 

mouths or from engaging in other hand-to-mouth 

activities. 

Since strontium is so common in the environment, 

and is naturally present in food and water, we 

cannot avoid being exposed to it. For several 

reasons, having a balanced diet with sufficient 

vitamin D, calcium, and protein will be protective 

by reducing the amount of ingested strontium that is 

absorbed. 

1.8 IS THERE A MEDICAL TEST TO 

DETERMINE WHETHER I HAVE BEEN 

EXPOSED TO STRONTIUM? 

All people have small amounts of stable strontium 

in their bodies, mostly in bone. It can be measured 

in the blood, hair, feces, or urine. The amount is 

usually measured by its mass (grams). 

Measurements in urine can show whether you have 

been exposed recently to larger-than-normal 

amounts of strontium. Measurements in hair can 

reveal whether you were exposed to high amounts 

of strontium in the past. Most physicians do not test 

for strontium in their offices, but can collect 

samples and send them to a special laboratory. Xrays can show changes in bone that may occur from 

exposure to high amounts of strontium, but these 

changes may have other causes (a diet low in 

vitamin D or a high exposure to some other trace 

metal). 

If a person has been exposed to radioactive 

strontium, special tests can be used to measure 

radioactive strontium in blood, feces, or urine. 

These tests are most useful when done soon after 

exposure, since radioactive strontium quickly enters 

into bone and takes many years to be completely 

removed from bone. Radioactive strontium can be 

measured by its mass (in grams) or by its radiation 

emissions. These emissions, which differ for the 

various isotopes of strontium, are used to tell the 

amount of radioactive strontium (in curies or 

bequerels) and the radiation dose that it gives to 

your body (in sieverts or rem). In a procedure that 

is similar to being x-rayed, specialized equipment 

can measure radioactive strontium that has been 

incorporated into bone. 

1.9 WHAT RECOMMENDATIONS HAS 

THE FEDERAL GOVERNMENT MADE 

TO PROTECT HUMAN HEALTH? 

The federal government develops regulations and 

recommendations to protect public health. 

Regulations can be enforced by law. Federal 

agencies that develop regulations for toxic 

substances include the Environmental Protection 

Agency (EPA), the Occupational Safety and Health 

Administration (OSHA), the Food and Drug 

Administration (FDA), and the U.S. Nuclear 

Regulatory Commission (USNRC). 

Recommendations provide valuable guidelines to 

protect public health but cannot be enforced by law. 

Federal organizations that develop 

recommendations for toxic substances include the 

Agency for Toxic Substances and Disease Registry 
 PUBLIC HEALTH STATEMENT 

 Strontium CAS#: 7440-24-6 

Division of Toxicology April 2004 

__________________________________________________________________________________________

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 

(ATSDR), the National Institute for Occupational 

Safety and Health (NIOSH), and the FDA. 

Regulations and recommendations can be expressed 

in not-to-exceed levels in air, water, soil, or food 

that are usually based on levels that affect animals; 

they are then adjusted to help protect people. 

Sometimes these not-to-exceed levels differ among 

federal organizations because of different exposure 

times (an 8-hour workday or a 24-hour day), the use 

of different animal studies, or other factors. 

Recommendations and regulations are also 

periodically updated as more information becomes 

available. For the most current information, check 

with the federal agency or organization that 

provides it. Some regulations and 

recommendations for strontium include the 

following: 

EPA recommends that drinking water levels of 

stable strontium should not be more than 

4 milligrams per liter of water (4 mg/L). 

The Department of Energy (DOE) established 

derived air concentrations (DAC) for workplace 

exposure to radiation at DOE facilities. The DAC 

ranges from 0.000000002 microcuries per milliliter 

(μCi/mL) (2x10-9 μCi/mL of air = 70 μBq/mL of 

air) for radioactive particles remaining in the lung 

for 100 days to 0.000000008 μCi/mL 

(8x10-9 μCi/mL of air = 300 μBq/mL of air) for 

radioactive particles remaining in the lung for less 

than 10 days. The USNRC established an annual 

intake limit of 20 μCi (7 MBq) for on-the-job 

exposure to 90Sr in air. 

EPA set standards for the concentration of 90Sr in 

community water supplies. The average annual 

concentration of 90Sr in water supplies should not 

exceed 8 pCi/L (0.3 Bq/L). EPA also established 

maximum contaminant levels (MCLs) in drinking 

water for radionuclide activities to protect against 

harmful effects of 90Sr. For beta particles like 

strontium, the MCL is 4 mrem per year (4x10-5 Sv 

per year). The USNRC set a workplace value of 

31 μCi (1.1 MBq) for the amount of 90Sr that can be 

taken in by mouth in a year without any harmful 

effects. 

1.10 WHERE CAN I GET MORE 

INFORMATION? 

If you have any more questions or concerns, please 

contact your community or state health or 

environmental quality department, your regional 

Nuclear Regulatory Commission office, or contact 

ATSDR at the address and phone number below. 

ATSDR can also tell you the location of 

occupational and environmental health clinics. 

These clinics specialize in recognizing, evaluating, 

and treating illnesses resulting from exposure to 

hazardous substances. 

Toxicological profiles are also available on-line at 

www.atsdr.cdc.gov and on CD-ROM. You may 

request a copy of the ATSDR ToxProfiles CDROM by calling the information and technical 

assistance toll-free number at 1-888-42ATSDR (1-

888-422-8737), by email at atsdric@cdc.gov, or by 

writing to: 

Agency for Toxic Substances and Disease Registry 

 Division of Toxicology 

 1600 Clifton Road NE 

 Mailstop F-32 

 Atlanta, GA 30333 

 Fax: 1-770-488-4178 
 PUBLIC HEALTH STATEMENT 

 Strontium CAS#: 7440-24-6 

Division of Toxicology April 2004 

__________________________________________________________________________________________

DEPARTMENT of HEALTH AND HUMAN SERVICES, Public Health Service

Agency for Toxic Substances and Disease Registry 

www.atsdr.cdc.gov/ Telephone: 1-888-422-8737 Fax: 770-488-4178 E-Mail: atsdric@cdc.gov 

For-profit organizations may request a copy of final 

profiles from the following: 

National Technical Information Service (NTIS) 

 5285 Port Royal Road 

 Springfield, VA 22161 

 Phone: 1-800-553-6847 or 1-703-605-6000 

 Web site: http://www.ntis.gov/