Californium

251.08

251.08

975X05H15A

DTXSID00225392

Alpha phase: hexagonal; beta phase: face centered cubic (metal)|In acidic solution Cf3+ is green and Cf4+ is yellow.

0

0.00000

15.1 g/mL at 25 deg C (alpha phase); 8.70 g/mL at 25 deg C (beta phase) (metal)

900 +/- 30 deg C (metal)

1100~1200ºC

There are 20 isotopes of californium that are now recognized(1). Californium-237 through 256 are artificially produced and all are radioactive(2).|DECAY PATHWAY: Californium-249, half-life 351 yrs, via alpha emission, 6.295 MeV, to curium-245, half-life 8,500 years|DECAY PATHWAY: Californium-250, half-life 13.08 yrs, via alpha emission, 6.128 MeV, to curium-246, half-life 4,760 years|DECAY PATHWAY: Californium-251, half-life 898 yrs, via alpha emission, 6.176 MeV, to curium-247, half-life 15,600,000 years|For more Other Experimental Properties (Complete) data for CALIFORNIUM, RADIOACTIVE (10 total), please visit the HSDB record page.

Slowly oxidized in air at room temperature; rate increases with increased moisture in air. Oxidized when warmed in air .

/SRP/ Wastes in the Waste Isolation Pilot Plant (WIPP) are from the nuclear weapons industry (plutonium) - research and development. For a waste to be accepted at WIPP it must be a transuranic "TRU" waste and: (1) /= 200 millirems/hr; if less, they can be contact handled.|Program design decisions can affect TRU waste-generation. For example, the quantity of protective clothing may be a significant factor. If an incinerator is available, combustible protective clothing may be selected to have a low ash content and generate a minimum of harmful effluents such as oxides of nitrogen or halogenated compounds. In other facilities, water-washable, reusable protective clothing may minimize waste disposal. /Plutonium facilities/|Another opportunity for waste minimization occurs when materials are used as a contingency protection against contamination. For example, strippable coatings may be applied to an area that is not expected to become contaminated or may receive only minor contamination so that it can be easily cleaned. Another example involves the disposition of disposable surgeons' gloves, which are routinely worn inside glove-box gloves. Unless there are serious contamination control problems in the facility, these can be surveyed and disposed of as sanitary waste rather than LLW or TRU waste. /Plutonium facilities/|Likewise, all tools and equipment to be placed in a contaminated environment should be tested for reliability and preferably used on a clean mock-up to ensure their serviceability before they become contaminated. There is often a temptation to put the equipment into the plutonium service when it first arrives rather than test it completely first. This can result in unnecessary waste volume. /Plutonium facilities/

...Reacts when heated with nitrogen, hydrogen or a halogen. Reacts rapidly with dry hydrogen halides and with aqueous mineral acids.

21 CFR 1002.20. Accidental Radiation Occurrences documents any actual or possible unexpected exposure during manufacturing, testing or use of ANY electronic product. Reports are due immediately after the event is known.

U.S. Nuclear Regulatory Commission; Regulatory Guide 8.34 - Monitoring Criteria and Methods to Calculate Occupational Radiation Doses. 1992/ Available at http://www.nrc.gov/reading-rm/doc-collections/reg-guides/occupational-health/active/8-34/index.html as of September 25, 2006|Eckerman KF et al; Federal Guidance Report No. 11 Limiting Values of Radionuclide Intake and Air Concentration and Dose Conversion Factors for Inhalation, Submersion, and Ingestion (1988) US Environmental Protection Agency EPA-5201/1-88-020. This resource may be accessed through homer.ornl.gov/VLAB/FedGR11.html for use in two ways; the tables may be accessed interactively by making a request for dose information on individual radionuclides for exposure scenarios of interest, or the Preface and Table of Contents may be viewed directly as in the hardcopy document. In addition, a copy of the printed document may be requested from the Dosimetry Research Group via email or obtained directly from EPA at http://www.epa.gov/radiation/federal/techdocs.htm|International Commission on Radiological Protection; ICRP PUBLICATION 66: HUMAN RESPIRATORY TRACT MODEL FOR RADIOLOGICAL PROTECTION, 66 Annals of the ICRP Volume 24/1-3, its accompanying tables in Publication 68 and the various volumes of ICRP Publication 30 address internal dosimetry calculations. According to the ICRP, the next fundamental Recommendations of ICRP are expected to be issued in 2007. As a consequence, dose coefficients for intakes of radionuclides given in Publications 30 and 68 and data for the interpretation of bioassay measurements in Publications 54 and 78 will need to be updated. ICRP also recognises the need to provide further guidance on the interpretation of bioassay measurements. A Supporting Guidance Document is in preparation, and will provide a significant development from the information given in previous ICRP reports on this topic.|Pacific Northwest National Laboratory; HANFORD: Radiation and Health Technology Methods and Models of the Hanford Internal Dosimetry Program. PNNL-MA-860 (2003) Available at http://www.pnl.gov/eshs/pub/pnnl860/pnnl860.pdf as of October 4, 2006|For more Special Reports (Complete) data for CALIFORNIUM, RADIOACTIVE (10 total), please visit the HSDB record page.

Protective clothing, commonly of Tyvex material, is used to keep contamination off personal clothing and skin. It does not stop the external radiation exposure (except alpha rays), but it helps prevent the spread of contamination both onto and into the body. /Plutonium facilities/|During operations in which there is a potential to breach a containment system (such as glove changes or seal-outs) and create airborne radioactivity, respiratory protection is the primary method of preventing internal dose from inhalation. To minimize the possibility of inhalation, individuals must ensure the physical integrity of the respirator, obtain a good seal, and ensure the protection factor of the respirator is adequate. There are also methods to prevent injection wounds (such as placing leather gloves over glovebox gloves or ensuring there are no sharp objects inside containments). If personnel have any suspicion of an injection wound, they should immediately seek the assistance of the site radiological control organization. /Plutonium facilities/|In most /emergency/ situations, respiratory protection that is designed to protect responders against chemical or biological agents is likely to offer some degree of respiratory protection in a radiological attack. Concerns about the presence of chemical or biological contaminants will influence the selection of respiratory protection. If used properly, simple face masks provide reasonably good protection against inhaling particulates, and allow sufficient air transfer for working at high breathing rates. If available, high-efficiency particulate air filter masks provide even better protection.

Radioactive material that presents a radiological risk: if material on fire or involved in fire, contact the local, state, or Department of Energy Radiological Response Team. Extinguish fire using agent suitable for type of surrounding fire. Cool all affected containers with flooding quantities of water. Apply water from as far a distance as possible.|Radioactive material, Type A package are materials that pose a minimal risk to transport workers, emergency response personnel and the public during transportation. If material on fire or involved in fire, contact the local, state, or Department of Energy Radiological Response Team. Do not use water. Use graphite, soda ash, powdered sodium chloride, or suitable dry powder.|Radioactive material, Type B(U) package is radioactive material in a package designed in such a way that it is unlikely to release its radioactive contents or lose its shielding integrity in accidents. In case of trouble with these shipments all unauthorized persons should be kept as far away as possible. If material on fire or involved in fire, contact the local. State, or Department of Energy Radiological Response Team. Extinguish fire using agent suitable or type of surrounding fire, Cool all affected containers with flooding quantities of water, Apply water from as far a distance as possible.|Radioactive material, Type C: if material on fire do not use water. Use graphite, soda ash, powdered sodium chloride, or suitable dry powder. If material not involved in fire, keep sparks, flames, and other sources if ignition away. Keep material out of water sources and sewers. Keep material dry. Do not attempt to sweep up dry material.

In most cases of contamination of equipment and buildings, a mixture of normal housecleaning methods will remove the material. Vacuum cleaners that can handle wet material and have high-efficiency filters are particularly useful. Some surfaces may require repeated scrubbing and vacuuming before they are free of contamination.|In most cases, contamination should be controlled, and removed as soon as possible. The contaminated area or equipment should be marked and posted immediately. Nonessential persons should be moved out of the area until decontamination has been completed. Usually simple cleaning techniques and procedures are adequate for most decontamination tasks. Spills and contaminated areas should be cleaned from the outer region inward to reduce the possibility of further spread of the contamination. After cleaning, the area or equipment should be surveyed to ensure that all the contamination has been removed.|Decontamination is most successful when the material can be recycled for use in a nuclear facility since the need to prove releasability (cleanliness) is eliminated. Nevertheless, cleaning material for unrestricted release is also possible in some cases. It may also be possible to decontaminate an item enough to change its classification from TRU/transuranic/ waste to LLW /low-level waste/, thereby allowing immediate disposal of the item, while a relatively small quantity of decontamination waste is stored as TRU waste. Electropolishing to remove the thinnest metal surface has been very effective and produces a relatively small waste volume, especially when one of the wetted sponge units is used rather than an emersion tank. Surface scabbling has been used in decontamination of concrete, and various abrasive blasting methods have also been effective. Strippable and self-stripping coatings may be used to decontaminate surfaces, even though the primary application of strippable coatings has been in preventing contamination of surfaces. /Plutonium facilities/

Techniques associated with conventional radiotherapy sources have been adapted for ... the safe use of neutron-emitting isotopes, such as californium-252 for interstitial and intracavitary radiotherapy. The use of source afterloading reduces the dose to personnel by eliminating source handling in sterilization procedures and in the surgical theater. In addition, the time required for source manipulation into implants can be minimized by using specialized instruments. Doses to nurses involved in routine care of the implanted patient can be at an acceptable level if a portable barrier is utilized when possible and if special training and practice are conducted.|A shielded facility for storage and handling of up to 300 ug of californium-252 afterloading cells and tubes was designed and constructed. The main shield consists of a centrally located lead pot surrounded by borated water-extended-polyester. A built-in, curved personnel barrier with sliding Lucite eye shield enables safe and rapid handling of sources during calibration, inventory, cleaning operations and movement to and from the source storage rods. The design radiation levels for the mixed neutron-gamma field from californium-252 were 3 mrem/hr at the surface of the shield, less than 2 mrem/hr in the corridor and adjacent radiotherapy patient room, and less than 0.2 mrem/lir in the nursing office below and patient room above. The protection survey of the completed facility and its environs confirmed the calculations and adequacy of the constructed shield. /Californium-252/|In any facility that handles radioactive materials, the major controls protecting workers, the public, and the environment are structures and installed equipment, which shield, contain, and confine the radioactive materials. However, to allow useful work to be performed in the facility and to assure that its protective features remain effective, a number of administrative controls are ordinarily required. These administrative controls are usually contained in a series of procedures related to the operations and maintenance activities to be carried out in the facility. All personnel who work in controlled areas should be familiar with the administrative controls that apply to their work. When changes or additions to administrative controls are made, these changes or additions should be effectively communicated to all persons who may be affected. /Plutonium facilities/|Radiation Protection Procedures: A ... facility should have a written policy on radiation protection, including a policy on keeping exposures ALARA. All radiation protection procedures and controls should have formal, recognizable technical bases for limits, methods, and personnel protection standards. Procedures should be adequately documented, updated periodically, and maintained in a centralized historical file. A control system should be established to account for all copies and ensure that all new procedures are included in the historical files. A designated period of time for maintaining historical files should be established. ... In addition, radiation protection procedures should have a documented approval system and established intervals for review and/or revision. A tracking system should be developed to ensure that the required reviews and revisions occur. /Plutonium facilities/|For more Preventive Measures (Complete) data for CALIFORNIUM, RADIOACTIVE (12 total), please visit the HSDB record page.

Regulating the safety of ... shipments /of radioactive materials/ is the joint responsibility of the NRC and the Department of Transportation (DOT). The NRC establishes requirements for the design and manufacture of packages for radioactive materials. The DOT regulates the shipments while they are in transit and sets standards for labeling these packages and for smaller quantity packages.

Radionuclides have been designated as a hazardous air pollutants under section 112 of the Clean Air Act. /Radionuclides/

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 1000 curies or 37 TBq. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b). /Californium-244/|Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 10 curies or 0.37 TBq. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b). /Californium-246/|Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 0.1 curie or 0.0037 TBq. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b). /Californium-248/|Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 0.01 curie or 0.00037 TBq. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b). /Californium-249/|For more CERCLA Reportable Quantities (Complete) data for CALIFORNIUM, RADIOACTIVE (9 total), please visit the HSDB record page.

Five-week-old male B6C3F1 mice were fed AIN-76B Purified Diet supplemented with nucleosides and nucleotides (NS) for 1 wk and 13 mo before and after irradiation of neutron with californium-252 (252-Cf); specifically NS was added to the AIN-76B Purified Diet (without nucleotide) to obtain a final concentration of 0%, 0.5%, or 2.5% NS. A commercial stock diet was also given to mice, and half of the mice were irradiated. Both irradiated and non-irradiated mice were used for reference controls. ... The incidence of liver tumors in each NS group was lower than that in the reference control group (P < 0.01), but there were no differences between the 0%, 0.5%, and 2.5% NS groups. In contrast, the incidence rate of mice with non-neoplastic lesions in the 0% NS group was significantly higher than the reference control group (P < 0.05). This higher incidence of mice with non-neoplastic lesions was significantly decreased upon supplementation of the nucleotide-free diet with 0.5% or 2.5% NS (P < 0.01 and P < 0.05, respectively). Of the non-neoplastic lesions observed, the incidence of amyloidosis was decreased significantly upon supplementation of the nucleotide-free diet with 0.5% NS (P < 0.05). ... /Californium-252 and nucleotide supplements/

/AQUATIC SPECIES/ ... a series of laboratory experiments using californium-252 was undertaken to assess californium bioavailability to benthic invertebrates. Californium-252 is readily taken up from sea water, reaching whole-body concentration factors of 763 in the polychaete Hermione hystrix, 220 in the shrimp Lysmata seticaudata, 665 in the crab Pilumnus hirtellus and 78 in the bivalve mollusc Venerupis decussata after 3 weeks' exposure. Surface sorption plays a predominant role in the uptake process as evidenced by the large fraction of californium-252 associated with the organisms' exoskeleton, shell and other external structures. Viscera and gills of clams, and gills, ovaries and viscera of crabs were also important sites of californium-252 accumulation. Depuration in clean sea water was a relatively slow process; biological half-lives for loss from a long-lived compartment ranged from 50 days in crabs and worms to 126 days in the clam. The shrimp Lysmata eliminated californium-252 very rapidly due to moulting. Absorption coefficients for ingested californium-252 were high, 23% in crabs and 97% in brittlestars. The absorbed fraction was excreted twice as fast from crabs ... as brittlestars ... . Exposure of organisms to labeled sediment resulted in low transfer factors that were species dependent (worms 0·05, clams 0·006). There is some evidence to suggest that uptake from sediments is primarily due to californium-252 transfer from the pore water. Comparison of these results with published experimental data on other transuranic nuclides in the same or similar species suggests that californium bioavailability is roughly equivalent to that of plutonium and americium. /Californium-252/|/AQUATIC SPECIES/ A catalog of biokinetic parameters for the transuranic elements plutonium, americium, curium, neptunium, and californium in marine invertebrates is presented. The parameters considered are: the seawater - animal concentration factor (CF); the sediment - animal concentration ratio (CR); transuranic assimilation efficiency; transuranic tissue distribution and transuranic elimination rates. With respect to the seawater - animal CF, authors differ considerably on how they define this parameter and a seven-point reporting system is suggested. Transuranic uptake from sediment by animals is characterized by low CRs. The assimilation efficiencies of transuranic elements in marine invertebrates are high compared to vertebrates and mammals in general and the distribution of transuranics within the body tissue of an animal is dependent on the uptake path. The elimination of transuranics from most species examined conformed to a standard biphasic exponential model though some examples with three elimination phases were identified. /Plutonium, americium, curium, neptunium, and californium/

Californium is artificially produced(1). Ten isotopes of californium are known and all are radioactive(1). Californium-251 is the most stable isotope of californium with a half-life of 900 years(2). Californium-245 was first produced at the University of California, Berkeley in 1950 by the bombardment of curium-242 with alpha particles in a cyclotron(1). Californium-252 is the only isotope of californium that has commercial uses and its uses are limited since it is only available in very small quantities(1). Californium's production may result in the release of californium compounds to the environment through various waste streams(SRC). Californium is used as a portable neutron source in core analysis in drilling oil wells and for the discovery of metals such as gold and silver(2); the production of these sources may result in the release of californium compounds to the environment through various waste streams(SRC). In addition, californium-252 is used in brachytherapy, where the californium-252 is in a sealed source, to treat various types of cancer(1). A small amount of californium would have been generated by atmospheric nuclear weapon testing, which ceased worldwide by 1980(1). A few californium compounds, including californium oxide (CfO3), californium trichloride (CfCl3) and californium oxychloride (CfOCl) have been produced and studied(2).

TERRESTRIAL FATE: Californium is typically insoluble and binds tightly to soils(1). Californium compounds are ionic and would not volatilize from moist or dry soil surfaces(SRC).|AQUATIC FATE: Californium(III) ions would be expected to adsorb to suspended particles in water, since actinide ions with III, IV, and VI oxidation states can be adsorbed to cation-exchange resins(1). Californium(III) is the only stable form in aqueous solution(1). Since californium compounds are ionic, they will not volatilize from water surfaces(SRC). Bioconcentration is not expected to be an important fate due to the ionic nature of californium compounds(SRC).|ATMOSPHERIC FATE: Californium compounds are ionic and would not be volatile and would exist solely in the particulate phase in the ambient atmosphere. Particulate-phase californium compounds will be removed from the atmosphere by wet or dry deposition. (SRC)

Bioconcentration is not expected to be an important fate due to the ionic nature of californium compounds. (SRC)

Californium(III) ions would be expected to adsorb to soil and suspended particles in water(SRC), since actinide ions with III, IV, and VI oxidation states can be adsorbed to cation-exchange resins(1). In general, metal cations in solution are attracted to the negatively charged surfaces of soil particles(2).

Californium compounds are ionic and would not volatilize from moist or dry soil surfaces or from water surfaces. (SRC)

Staff involved in radiotherapy with neutrons are exposed mainly to gamma and beta-rays due to activation of the room and equipment. The dose rates are well below 1 uGy/ per hour and are not detectable by personal dosimetry.|... the use of californium has proven feasible in the treatment of more than 20 neoplastic lesions of patients. The maximum probable dose received by radiotherapists has been 1.1 mrem per microgram of californium-252 implanted in regions of the head and neck, skin, and pelvis. Each attending nurse is estimated to have received 2 mrem per microgram implanted.|Occupational exposure to californium compounds may occur through inhalation and dermal contact with this compound at workplaces where californium is produced or used(SRC). Since californium has limited uses and is produced in only small quantities(1), exposure to californium would be expected to be limited to individuals involved with the research activities and production of californium(SRC). Californium-252 is used in brachytherapy to treat various cancers(1). In this application, californium-252 is contained within a sealed source(1).

The use of californium-252 in brachytherapy is expected to be more effective with the therapy of bulky tumors than the conventional therapy with photons. .../Californium-252/|Interest in the neutron-emitting californium-252 radioisotope as a radiotherapy nuclide has undergone a resurgence given recent efforts to fabricate HDR remotely afterloaded sources, and other efforts to create a miniature source for improved accessibility to a variety of anatomic sites. Therefore, HDR 252-Cf brachytherapy may prove to be a potential rival to the use of HDR iridium-192 remotely afterloaded brachytherapy--the current standard-of-care treatment modality using HDR brachytherapy. ... /Californium-252/|Californium-252 is a neutron-emitting radioisotope used as a brachytherapy source for radioresistant tumors. Presented here are microdosimetric spectra measured as a function of simulated site diameter and distance from applicator tube 252-Cf sources. These spectra were measured using miniature tissue-equivalent proportional counters (TEPCs). An investigation of the clinical potential of boron neutron capture (BNC) enhancement of 252-Cf brachytherapy is also provided. The absorbed dose from the BNC reaction was measured using a boron-loaded miniature TEPC. Measured neutron, photon and BNC absorbed dose components are provided as a function of distance from the source. In general, the absorbed dose results show good agreement with results from other measurement techniques. A concomitant boost to 252-Cf brachytherapy may be provided through the use of the BNC reaction. The potential magnitude of this BNC enhancement increases with increasing distance from the source and is capable of providing a therapeutic gain greater than 30% at a distance of 5 cm from the source, assuming currently achievable boron concentrations. /Californium-252/|To observe the therapeutic effectiveness and complications of californium-252 (252-Cf) brachytherapy in cervical cancer: Fifty one cases of cervical cancer were diagnosed according to the standard of the International Federation of Gynecology and Obstetrics (FIGO), II a:8 cases, II b:31 cases, III a:8 cases, III b:4 cases. Treatment schedule: 252-Cf after loading brachytherapy, 10-12 Gy/fraction/week, the total dose of reference point A was 36-40 Gy in three to four implant sessions. In the second day after 252-Cf therapy, the whole pelvis was treated with 6 MV X-ray external beam radiotherapy, 200 cGy per fraction, 4 times per week. The total dose of external beam radiotherapy was 40 to 50 Gy (the middle of pelvis was blocked at width of 4 cm after 20-30 Gy), then the total dose of reference point B was 50-55 Gy; the total treatment time was 5-6 weeks ... The average time of complete tumor regression was 25 days, the local control rate of 2 year was 100%, the total 2 year survival rate was 92%, i.e., II a: 8/8 cases, II b: 30/31 cases (97%), III a: 6/8 cases, III b: 3/4 cases; the late radiation complications of bladder and rectum was 2% respectively during these 2 years. /The authors/ concluded that combined 252-Cf brachytherapy and high energy X-ray external beam radiotherapy may be safe and effective in the management of cervical cancer. 252-Cf has advantages of high local control rate; rapidly regression of bulky tumors and low-grade radiation complications|For more Therapeutic Uses (Complete) data for CALIFORNIUM, RADIOACTIVE (7 total), please visit the HSDB record page.

No one specific type of secondary cancer is seen after therapeutic irradiation. Secondary cancers can occur after any initial cancer, when survival surpasses the latent period. Radiation-induced leukemias begin to appear after 3-5 years. Solid cancers typically emerge more than 10 years after treatment but may occur earlier in particularly susceptible individuals. When the risk of secondary solid cancer is elevated, it rises with increasing radiation dose to the site and with increasing time since treatment and persists as long as 20 years.

The metabolism of californium was studied in 11 beagles 0-160 days after intravenous injection of californium-249 or californium-252 as Cf (III) citrate. Total excreta collections were made for the first 21 days after injection, and the samples were analyzed for their californium content by gamma-ray counting of the 333 and 388 keV gamma-rays of californium-249 or the fission gamma-rays of californium-252. It was found that the excretion of californium during this period was mainly in the urine. ... A combination of total-body and partial-body counting was used to determine serially the total-body retention and partitioning of retained californium between liver and non-liver tissue. These measurements indicated that 1 week following injection, about 20% of the injected californium was deposited in the liver and that about 60% remained in non-liver tissue (mainly skeleton). The relative bone-to-bone distribution of californium-249 in the skeletons of 2 dogs sacrificed 7 and 21 days after injection was similar to that of americium-241 and plutonium-238Pu injected as citrates. /249,252Cf(III)citrate/|The microscopic distribution pattern of californium-249 and berkelinium-249 in the soft tissues of beagles, one to three weeks following a single intravenous injection of a citrate solution, was found to be very similar to that of plutonium-241 > americium. Relatively high concentrations occurred in the hepatic cells of the liver, the glomeruli of the kidney, the interfollicular region of the thyroid, the cartilaginous tissues of the lung, and the media of the smaller arterioles of most organs. Very intense, but sparsely scattered "hot spots" were also present in the renal papillae and in the submucosa of the bronchioles. Lesser sites of localization were the endocardium of the AV heart valves, the glassy membranes of the larger hairs of the coat, the zona pellucida of the Graafian follicles and the zona arcuata of the adrenal cortex. With the exception of the liver, where the radionuclide was principally within the hepatic cells, most of the deposition sites were extracellular, within or associated with connective tissue which gave a positive periodic acid-Schiff reaction. /Californium-249 and berkelinium-249 citrates/|Beagles were injected with californium-249 or californium-252 in citrate buffer. The concentration of nuclide in plasma and whole blood was measured from 5 min to 48 hr post injection. Small amounts of californium were found associated with the cellular elements. The concentration of californium in plasma decreased rapidly during the first few hours after injection. At 24 hr post injection less than 1 % of the injected dose was circulating. Californium-249 and -252 disappeared from the circulation at the same rate. Separation of plasma constituents by gel filtration demonstrated that californium in plasma was associated with compounds with a molecular weight of approximately 70,000. Additional information obtained by ion exchange chromatography indicated that this protein was transferrin. Data obtained in vivo from canines were extended by in vitro experiments with human blood. Gel chromatography of human plasma protein incubated in vitro with californium indicated that a californium protein complex was formed and appeared to be nearly identical to that seen in dogs. Re-chromatography of these fractions on DEAE-Sephadex showed that transferrin and californium did not coincide exactly. Thus californium-transferrin is either held more tenaciously by the ion exchange resin than iron-transferrin or apo-transferrin, or the shift was caused by the presence of another as yet un-identified minor protein component. The stability of the protein complex(s) formed is less than that of the plutonium-transferrin complex and this decreased stability is responsible for the high rate of its disappearance from the bloodstream. /Californium-249 and californium-252 citrates/|Young adult beagles are given single intravenous injections of monomeric californium-252, californium-249, americium-24, plutonium-239, thorium-228, radium-226, radium-228 or strontium-90 in citrate solution to achieve reproducible deposition patterns in tissue. Injected transuranium atoms become attached to transferrin and other substances in blood plasma. The skeleton and liver are the primary sites of deposition, although high local concentrations of californium, berkelium and americium also occur in the thyroid and kidney, and radium also concentrates in the eye. The initial skeletal deposition of monomeric transuranium elements is on bone surfaces. The mean local dose-rate to the soft-tissue layer 0-10 mi from the mineralized bone surfaces of the beagle is about 20 times higher when 239-Pu is on bone surfaces than for an equal amount of 239-Pu randomly distributed throughout the bone mineral. Thus, the rate of bone-surface remodeling has a very important influence on the skeletal toxicity of the transuranium elements. The initial liver deposition of monomeric transuranium elements is rather uniform and mainly in the hepatic cells. Subsequently, much of the radioactivity shifts into the liver reticulo-endothelial cells that line the sinusoids. At long times after injection, the distribution is very non-uniform, being highest in the portal region and lowest in the regenerative nodules... /Californium-252, californium-249, americium-24, plutonium-239, thorium-228, radium-226, radium-228 or strontium-90 citrates/|Radioactive atoms of radionuclides of the actinide and lanthanide series and other easily hydrolyzable metallic radionuclides ... may tend to aggregate and concentrate within lysosomes. This creates a non-uniform distribution of the radioactivity at the intracellular level, which could in principle lead to more intense radiation-induced changes in the immediate vicinity of the decaying atom. /Lanthanides and actinides/

Radionuclide: Californium-252, Physical Half Life: 2.6 years, Effective Half Life: 2.2 years. /From table; Californium-252/

The mean free path of neutrons in tissues varies with their energy from a fraction to several tens of centimeters. Since neutrons are uncharged, they do not interact directly with orbital electrons in tissues to produce the ions that initiate the chemical events leading to cell injury. Rather, they induce ionizing events in tissues mainly by elastic collision with the hydrogen nuclei of the tissue molecules; the recoiling nucleus (charged proton) is the source of ionizing events. As about half of the neutron's energy is given to the proton on each collision, the low-energy neutrons provide an internal source of low-energy protons deep within body tissues. The low-energy protons form densely ionizing tracks (high linear energy transfer (LET)) which are efficient in producing biological injury. The ICRP (1991) therefore defined weighting factors for estimating the risks associated with exposure to neutrons which are larger than those for X- or alpha radiation. Neutrons with an energy of about 1 MeV are judged to be the most injurious.

Basic Treatment. Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 mL/min. Monitor for shock and treat if necessary. Anticipate seizures and treat if necessary. Perform routine emergency care for associated injuries. ... Perform routine basic life support care as necessary. /Radioactives I, II, and III/|Advanced Treatment. Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious or is in severe respiratory distress. Monitor cardiac rhythm and treat arrhythmias as necessary. Start IV administration of 0.9% saline (NS) or lactated Ringer's (LR) TKO. For hypotension with signs of hypovolemia, administer fluid cautiously. Watch for signs of fluid overload. Treat seizures with diazepam or lorazepam. Perform routine advanced life support care as needed. Use proparacaine hydrochloride to assist eye irrigation. /Radioactives I, II, and III/|Special Considerations. Most symptoms from radioactive product exposure are delayed; treat other medical or trauma problems according to normal protocols. An accurate history of the exposure is essential to determine risk and proper treatment modalities. The dose of radiation determines the type and clinical course of exposure: 100 rads: GI symptoms (nausea, vomiting, abdominal cramps, diarrhea). Symptom onset within a few hours. 600 rads: Several GI symptoms (necrotic gastroenteritis) may result in dehydration and death within a few days. Several thousand rads: neurological/cardiovascular symptoms (confusion, lethargy, ataxia, seizures, coma, cardiovascular collapse) within minutes to hours. Bone marrow depression, leukopenia, and infections usually follow severe exposures./Radioactives I, II, and III/|Emergency and supportive measures. Depending on the risk to rescuers, treatment of serious medical problems takes precedence over radiologic concerns. If there is a potential for contamination of rescuers and equipment, appropriate radiation response protocols should be implemented, and rescuers should wear protective clothing and respirators. Note: I the exposure was to electromagnetic radiation only, the victim is not contaminating and does not pose a risk to downstream personnel. 1. Maintain an open airway and assist ventilation if necessary. 2. Treat coma and seizures if they occur. 3. Replace fluid losses from gastroenteritis with iv crystalloid solutions. 4. Treat leukopenia and resulting infections as needed. Immunosuppressed patients require reverse isolation and appropriate broad-spectrum antibiotic therapy. Bone marrow stimulants may help selected patients. /Radiation (Ionizing)/|For more Antidote and Emergency Treatment (Complete) data for CALIFORNIUM, RADIOACTIVE (6 total), please visit the HSDB record page.

/CASE REPORTS/ A general description of a californium-252 inhalation incident, personnel decontamination and precautionary medical treatment are presented in this paper. Californium urinary excretion was followed, some fecal analyses were carried out and in vivo measurements were made with a 4x8 inch NaI(Tl) detector. Bioassay data are evaluated to indicate gastrointestinal and urinary clearance rates. The effects of DTPA chelation and catharsis are discussed. /Californium-252/|/OTHER TOXICITY INFORMATION/ Effects of cobalt-60 gamma-rays and californium-252 neutrons on human sperm chromosomes were studied using an interspecific in vitro fertilization system to estimate relative biological effectiveness (RBE) of neutrons. Semen samples were exposed to 0.5, 1.0 and 2.0 Gy of cobalt-60 gamma-rays at 1.7 centaGy/ min and 0.25, 0.5 and 1.0 Gy of californium-252 radiation at 1.3-1.7 cGy/ min. In the cobalt-60 experiment, 509 spermatozoa from controls and 902 spermatozoa from the irradiated groups were karyotyped, while in the californium-252 experiment 460 control and 804 irradiated spermatozoa were analysed. In both ... experiments, incidences of spermatozoa with radiation-induced structural chromosome aberrations increased linearly with increase of dosage. The RBE of californium-252 neutrons for the induction of chromosomally abnormal spermatozoa was estimated to be 1.6. The number of induced structural chromosome aberrations per spermatozoon also increased linearly. The RBE of neutrons for this index was 2.0. Among structural chromosome aberrations observed, chromosome-type breaks were predominant in both cobalt-60 and californium-252 experiments, and they showed a significant linear dose-dependent increase. Other types of aberrations such as chromosome-type exchanges and chromatid-type breaks also increased linearly with increase in dose. The RBEs of californium-252 neutrons for the induction of these three types of aberrations were 1.6, 3.2 and 3.9, respectively. Thus, the RBEs of neutrons for the induction of chromosome aberrations were smaller in human spermatozoa than in human lymphocytes, and mouse spermatogonia and embryos. ... /Californium-252 and cobalt-60/

Californium

Californium-249, prepared by transuranic processing following sequential neutron captures in transuranic isotopes. Sold in microgram quantities as solutions or solid nitrate or chloride at radiopurity of >98% and shipped in nonreturanable glass bottles. Classed as a nuclear material requiring documentation of transfer.|Californium-252, prepared by transuranic processing following sequential neutron captures in transuranic isotopes. Sold in microgram quantities as solution or custom forms at radiopurity of >80 to 85 atom % and shipped in welded stainless steel container meeting special form requirements. Classed as a nuclear material requiring documentation of transfer.

Because californium-252 does spontaneously fission, thereby releasing neutrons, it can be used as a neutron source - a startup fuel - to initiate the uranium-235 chain reaction. One inserts the californium-252 into the reactor to "fire" it up and start the production of electricity. Californium-252 is also used in security devices as a means to detect the presence of hidden explosives such as one might uncover in an airport.|Californium-252 is also used in security devices as a means to detect the presence of hidden explosives such as one might uncover in an airport. Many explosives are composed of nitrogen-containing chemical compounds. Nitrogen-14 , the most abundant isotope of nitrogen, has a relatively large affinity for capturing neutrons. After the nitrogen captures the neutron, the nitrogen is in an excited state and loses energy by emitting a characteristic gamma ray. ... By irradiating a suspected item with neutrons, these gamma rays may be detected and inform the security agents that an explosive is possibly present.|A third way in which neutrons can be released is by collision of charged particles with a lithium or beryllium target, when part of the neutron binding energy in the nucleus of lithium or beryllium is converted into kinetic energy of 14 to 66 MeV. Radionuclides /such as californium-252/ and ion accelerators that emit alpha-particles are used to initiate these reactions, and the neutrons emitted are used for radiography and radiotherapy.|Higher-neutron-flux reactors, such as those at the Savannah River Plant in South Carolina and the High Flux Isotopes Reactor at Oak Ridge National Laboratory in Tennessee produce gram quantities of californium.|For more General Manufacturing Information (Complete) data for CALIFORNIUM, RADIOACTIVE (6 total), please visit the HSDB record page.