Medical exposure

Specialized equipment used for medieal procedures often contains PVC components. Most often, the PVC used contains DEHP because this plasticizer imparts desirable flexibility and strength. For example, in PVC blood bags, DEHP may constitute as mueh as 40 percent of the plastic material. Other phthalates are not readily used in medieal deviees. In 1997, the IPCS reported a DBP level of 5 mg/g in plastic tubing nsed for oral/nasal feeding. There are no known nses of DnHP nor DNOP-eontaining medical devices. BBP is not approved by the FDA for use in medical devices.  

Health and Safety Issues with Plasticizers and Plasticized Materials 

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Pre-employment medical for selection and establishment of base levels Working conditions in specific areas Employees routine medicals, exposure profiles Biological monitoring where appropriate... 

PM 77 Fitness of equipment used for medical exposure to ionising radiation... 

Employee and environmental health data records system. Maintains medical exposure data of employees. 

The incidence of congenital malformation is approximately 3% to 5%, and it is estimated that 1% of all birth defects are caused by medication exposure. Adverse fetal drug effects depend on dosage, route of administration, concomitant exposure to other agents, and stage of pregnancy when the exposure occurred. 

By contrast, functional magnetic resonance imaging obviates the need to use ionizing radiation. Early results have been intriguing (Vaidya et ah, 1998 Rubia et al., 1999) but important confounds such as medication exposure, first-dose effects, and small sample size require replication. 

Medical exposures have been steadily reduced. A chest x-ray in 1945 often was taken on 35-rmn film, involving a dose of approximately 10 mGy (1 rad) in contrast, the dose it involves at a good clinic today is about 0.05-0.1 mGy (5-10 mrad) to the thoraxic area For some diagnostic x-ray procedures, higher exposures are involved—a GI series may involve a dose of 10 mGy (1 rad) to the abdominal area Thble 8.3 lists the effective dose equivalents and the estimated risks associated with various activities. 

One case has been reported of liver angiosarcoma (pathologically confirmed) in a worker exposed to polychloroprene who had no known occupational exposure to vinyl chloride (lARC, 1987b) or medical exposure to thorotrast (Infante, 1977). [It is unclear whether and how much this worker was exposed to chloroprene monomer.]... 

DEHP also can enter your body during certain medical procedures, and medical exposures are likely to be greater than any environmental exposures. Blood products that are stored in plastic bags and used for transfusions contain from 4.3 to 1,230 parts of DEHP per million parts of blood (ppm). Other plastic medical products also release DEHP. Flexible tubing used to administer fluids or medication can transfer DEHP to the patient. The plastic tubing used for kidney dialysis frequently contains DEHP and causes DEHP to enter the patient s blood. DEHP... 

Medical exposure to DEHP routinely occurs during intravenous infusion of blood and blood products (e.g., fluids and medication). Rapid elimination of DEHP that reaches the blood during transfusions and hemodialysis has been demonstrated in several studies (Barry et al. 1989 Lewis et al. 1978 Rubin and Schiffer et al. 1975 Sjorberg et al. 1985). For example, transfusion of platelets that were stored in vinyl plastic packs resulted in blood levels of DEHP (peak plasma concentrations ranging from 0.34 to 0.83 mg/dL) that fell monoexponentially with a mean rate of 2.83% per minute and a half-life of 28 minutes (Rubin and Schiffer 1975). Similarly, measurements on patients who had undergone >50 hemodialysis treatments indicated that most of the DEHP present in the serum at the completion of a dialysis session is likely to be gone in 5-7 hours (Lewis et al. 1978). 

In 1958, the International Commission on Radiological Protection (ICRP) recommended that the genetic dose to the general population, excluding natural background radiation, not exceed 5 rems plus the lowest practicable contribution from medical exposure in a 30-yr period, or 170 mrems/yr. 

Bustillo JR, Lauriello J, Rowland LM, Thomson LM, Petropoulos H, et al. 2002. Longitudinal follow-up of neurochemical changes during the first year of antipsychotic treatment in schizophrenia patients with minimal previous medication exposure. Schizophr Res 58 313-321. 

Radiation other tlian radon Estimated 360 cancers per year. Mostly from building materials. Medical exposure and natural background levels not included. 

A prospective upper bound on the individual dose which is used in the optimisation of protection and safety for sources. For occupational exposures, dose constraint is a source-related value of individual dose used to limit the range of options considered in the process of optimisation. For public exposure, the dose constraint is an upper bound on the annual doses that members of the public should receive from the planned operation of any controlled source. The exposure, to which the dose constraint applied is the annual dose to any critical group, summed over all exposure pathways, arising from the predicted operation of the controlled source. The constraint for each source should ensure that the sum of doses to the critical group from all controlled sources remains within the dose limit. For medical exposure the dose constraint levels should be interpreted as guidance levels, except when used in optimising the protection of persons exposed for medical research purposes or of persons, other than workers, who assist in the care, support or comfort of exposed patients. 

Exposure incurred by members of the public from radiation sources, excluding any occupational or medical exposure and the normal local natural background radiation but including exposure from authorised sources and practices and from intervention situations. 

All three principles apply to the protection of workers and the public. However, to protect patients during the medical use of ionising radiation only justification and optimisation apply. Dose limits are not applicable to medical exposure, but guidance levels which show what is achievable by good practice may be established for use by medical practitioners. Dose limits are also inapplicable to interventions, which are concerned with reducing exposure. 

Certain medical exposures, e.g., the exposure of population groups for mass screening, unless the benefit outweighs the risk. 

Medical exposures should be justified by weighing the diagnostic or therapeutic benefits they produce against the radiation detriment they might cause, taking into account the benefits and risks of available alternative techniques that do not involve medical exposure. 

The dose limits specified here apply to exposures attributable to practices, with the exception of medical exposures from natural sources that cannot reasonably be regarded as being under the responsibility of any principal party of the Standards. 

Antimony salts have in the past found many uses in medicine, and antimony compounds, especially penta-valent ones, are still used to treat Schistosoma japoni-cum infestation and leishmaniasis (2). Antimony is also used as an emetic. Attention is being paid to the anticancer potential of antimony compounds (3,4). As with many other metals, occupational and environmental exposure is possible and can act additively with medical exposure. 

Gerdsen R, Stockfleth E, Uerlich M, Fartasch M, Steen KH, Bieber T. Papular palmoplantar hyperkeratosis following chronic medical exposure to arsenic human papillomavirus as a co-factor in the pathogenesis of arsenical keratosis Acta Derm Venereol 2000 80(4) 292-3. 

Allergic contact dermatitis has apparently been most commonly due to occupational exposure of building workers to a form of cement containing a water-soluble form of chromium (SEDA-20,208) (15). Such reactions to medical exposure have not been described but could in principle occur. 

In man, a number of epidemiological studies using different designs have been conducted (17) on the health risks of non-medical exposure to formaldehyde and also in health-care professionals (18-23), with contradictory results. Cancers in excess in more than one study were Hodgkin s disease (24,25), leukemia (18,19,22,23,26), cancers of the buccal cavity and pharynx (particular the nasopharynx) (18,19,25,27,28), lung (18,24,27,29-31), nose (32-36), prostate (19,24,26), bladder (19,23,26), brain (20), colon (18-20,25,27), skin (18,25), and kidney (27). 

Finally, as with other metallic elements, non-medical exposure to manganese can occur, particularly in occupational settings, and can cause neurotoxicity (3). 

Contact dermatitis as a reaction to nickel is well known but usually reflects continuing non-medical exposure, for example among hairdressers (16) nickel released from injection needles and from Dermojets can, however, also give rise to cutaneous hypersensitivity reactions. 

A summary of the contributions of the various natural and man-made radiation sources to our radiation background is given in Table 3. It can be seen that natural sources contribute 82% of the total, with radon being the largest single source (67% of natural radiation dose). Of the 18% contributed by man-made sources, medical exposure is the most prominent (83%). Attempts to significantly reduce population radiation doses would most likely be focused on the largest contributors, that is, indoor radon and medical radiation. 

Honey-colored crusted plaques with bullae, but may begin as vesicles regional distribution, mild or no systemic symptoms History of medication exposure generalized rash... 

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