Management of occupational exposure for pregnant workers in the medical field in Spain Emilio Casal. Centro Nacional de Dosimetría. Valencia Belén Fernández. Hospital General de Asturias. Oviedo Mª Jesús Manzanas. Hospital 12 de Octubre. Madrid Ignacio Amor, Ana Blanes, Gloria Martí, Mª Dolores Rueda. Consejo de Seguridad Nuclear. Madrid Spain

Control of the occupational exposure of pregnant women Measures for women who are not pregnant are the same as for men. After pregnancy declaration, special protection for the unborn child has to be provided … … comparable with that provided for members of the general public. … not creating unnecessary discrimination against pregnant women. But, ... how is this special protection put into practice? Occupational exposure of pregnant workers

How has this special protection been implemented? It has been established a cooperation among: Nuclear Safety Council (CSN) Spanish Medical Physics Society (SEFM) Spanish Radiation Protection Society (SEPR) …within the Radiological Protection Forum … creating a specific working group to study the practical application of fetal protection The main conclusions of this group are presented in this paper Occupational exposure of pregnant workers

Main conclusions of the Working Group Information on fetal risks and protection measures … for physicians and pregnant workers Introduction of practical dose limits … related to dosemeter readings Evaluation of working conditions … to fulfil the adequate protection of the fetus Supplementary individual monitoring … to verify that dose limits have not been exceeded Occupational exposure of pregnant workers

Information on fetal risks and protection measures Physician´s guide … intended to gynaecologists, obstetricians and medical professionals in charge of the medical surveillance of exposed workers Pregnant worker guide … main information to give to female exposed workers Occupational exposure of pregnant workers

Occupational exposure of pregnant workers Physician’s Guide  Main ideas to be transmitted to physicians: Specific biological effects of ionizing radiation to be considered during the pregnancy.  Deterministic fetal effects appear only for doses exceeding the threshold of 100-200 mSv.  The increment of probabilistic effects due to radiation exposure for doses about 1 mSv is much smaller than the spontaneous incidence rate of fatal childhood cancers that is about 2-3 per 1000. The fetal dose limit of 1 mSv for the remainder of the pregnancy, after it is declared, provides an adequate protection to the fetus: it has been established based on ethical rather than fetal risk considerations.    Occupational exposure of pregnant workers

Pregnant Worker's Guide Main information to give to female exposed workers:   You must notify your pregnancy to the employer … in order to decide the best protection methods for the fetus  You must follow the guidances on radiation protection … in order to keep doses to the fetus to a minimum  You must wear a dosemeter on your abdomen ... to check that doses to the surface of the abdomen do not exceed the practical limit of 2 mSv during the remainder of the pregnancy Finally, if your working conditions are such that doses to the abdomen should keep lower than 2 mSv, you can feel safe enough in your position during the rest of your pregnancy. Occupational exposure of pregnant workers

Declaration of Pregnancy This is to inform you that I am currently pregnant, in order to guarantee that the additional protection measures, foreseen in the corresponding regulations, are applied   Name:...……………………….... National Identification Document: ....….. I am currently working in the following area …….................... …... I am ___ weeks pregnant. My expected delivery date is…….. …... Date of the declaration.................…………………............ Signature of the worker Signature of the Radiation Protection Officer Signature of the Physician in charge of the medical surveillance of exposed workers Occupational exposure of pregnant workers

Occupational exposure of pregnant workers Practical dose limits A supplementary equivalent-dose limit to the surface of the woman´s abdomen (lower trunk) of 2 mSv for the remainder of the pregnancy has been proposed Nuclide intakes SHOULD be limited to about 1/20 of the ALI ... as proposed by ICRP’60 but unfortunately not incorporated in the Directive 96/29 or in the Spanish Regulation Occupational exposure of pregnant workers

Evaluation of working conditions from previous dose information If equivalent-dose to the surface of the abdomen: A: with certainty will be less than 2 mSv ... no change needs to be made B: is likely to be less than 2 mSv ... initiatives to reduce the probabilty of possible exposures should be taken C: is likely to be above 2 mSv ... Pregnant worker shall be transferred to other work (A or B) Occupational exposure of pregnant workers

Workers with annual doses exceeding Distribution of annual doses exceeding levels of reference (Data from CND) Year 2000 Exposed workers Workers with annual doses exceeding 2 mSv 5 mSv 50 mSv Women 20.095 337 (1,7%) 72 (0,36%) Men & women 31.881 636 (2,0%) 146 (0,46%) Occupational exposure of pregnant workers

Occupational exposure of pregnant workers Distribution on categories and working types of cases exceeding the limit of 2 mSv. (Data from CND) Women. Year 2000 Physicians Nurses Technicians Other Radiology (General Practice) 1 (0,42%) 2 (0,40%) 9 (1,1%) 2 (0,24%) Radiology (Hospital) 14 (1,3%) 7 (0,42%) 9 (0,33%) 6 (0,24%) Vascular Radiology 8 (7,3%) 17 (5,1%) 1 (2,6%) 1 (0,58%) Surgery 3 (0,56%) 25 (0,62%) 1 (3,6%) 8 (0,49%) Radiotherapy 13 (4,5%) 4 (1,8%) 2 (0,62%) Nuclear Medicine 15 (8,6%) 113 (57,4%) 37 (27,8%) 36 (13,6%) 1 (0,25%) 1 (0,34%) Occupational exposure of pregnant workers

Working restrictions: Diagnostic Radiology In general a pregnant worker CAN CONTINUE doing her job as long as she stays behind structural protection barriers Pregnant workers SHOULD NOT work without structural protection barriers (fluoroscopy and mobile radiographic and fluoroscopic screening equipment) Pregnant workers SHALL NOT participate in any emergency programme. Occupational exposure of pregnant workers

Working restrictions: Nuclear Medicine It will be necessary to avoid any significant risk of bodily radioactive contamination. Pregnant workers SHALL NEITHER handle radiopharmaceuticals in controlled areas NOR participate in the care of patients under metabolic therapy. Pregnant workers SHOULD NOT administer or inject radiopharmaceuticals to patients. Pregnant workers SHALL NOT participate in any emergency programme   Occupational exposure of pregnant workers

Working restrictions: Radiotherapy In general a pregnant worker CAN CONTINUE doing her job using linear accelerators and automatic after-loading brachytherapy  SHALL NOT work in cobalt units due to the possibility of emergencies. SHALL NOT handle radioactive sources in manual brachytherapy techniques. SHOULD NOT participate in the care of patients being treated with manual brachytherapy techniques. SHALL NOT participate in any emergency programme Occupational exposure of pregnant workers

Working restrictions: Special situations To avoid any working discrimination exceptionally pregnant women work could be allowed in the cases: Mobile radiographic X-ray equipments, Fixed and mobile fluoroscopic X-ray equipments, Administration and injection of radiopharmaceuticals in NM Nursing of patients under treatment with manual BT with the following conditions: pregnant worker voluntarily declares her decision of continuing working conditions make it unlikely that the equivalent dose to the surface of the woman’s abdomen will exceed 2 mSv a radiation protection service will verify those conditions, supervising it during the remainder of the pregnancy. Occupational exposure of pregnant workers

Pregnant women’s external exposure monitoring Doses to the abdomen of the pregnant woman will be estimated using an individual dosemeter: placed on her abdomen additional to the other dosemeter used to evaluate whole body doses adequately identified (“abdomen dosemeter”) Doses to the abdomen should be registered independently from whole body doses But remember ... “The dose to the fetus is not directly comparable to the dose measured on a dosemeter placed on the abdomen” Occupational exposure of pregnant workers

Pregnant women’s internal dosimetry It is necessary to avoid any significant risk of radioactive intake by pregnant exposed workers. If the intake probability would be negligible, there will be no need to implement any systematic assessment of internal doses to the fetus  Individual monitoring for intakes of fetus is extremely complex and with a high level of uncertainty. However, in case of internal contamination of a pregnant exposed worker, there are methods to estimate fetal doses (ICRP’88) Occupational exposure of pregnant workers

Occupational exposure of pregnant workers: Conclusions Information on actual risks to the fetus should be given to physicians and pregnant exposed workers. Working conditions of pregnant worker shall be reviewed after pregnancy declaration. Practical dose limit to the abdomen of 2 mSv during the remainder of the pregnancy has been proposed. Additional dosemeter to be placed on the abdomen is required. … in these conditions an exposed pregnant worker can feel safe enough in her job during the rest of the pregnancy. Occupational exposure of pregnant workers