Radioactive materials and various ionizing and non-ionizing radiation-producing devices are extensively used in Israel in many areas and applications medical diagnosis and therapy, industry, agriculture, research and development, and others. In order to avoid unnecessary exposure, a radiation protection infrastructure consisting of legislation, education, licensing and supervision was developed in Israel.
Supervision over Radioactive Elements
Supervision over radiation safety in the realm of radioactive materials and the environment is based on the Pharmacists Regulations (Radioactive Elements and Products Thereof). The regulations were first promulgated in 1980 and amended in 1991. The regulations prohibit the purchase, distribution, transport and application of radioactive materials and other radiation sources unless a special license has been issued by an authorized radiation officer, appointed by the Minister of Health, with respect to radiation for medical purposes, or by the Minister of the Environment with respect to "cradle to grave" control of radiation in all other sectors. The regulations encompass all components of radiation both ionizing and non-ionizing including radioactive isotopes, environmental radiation, radon, ultra-violet, infra-red, lasers and electro-magnetic waves in micro and radio frequencies. Special conditions may be attached to the permit to ensure environmental safety and individual and public health; a permit may be canceled if these special conditions or the conditions stipulated by the regulations are not kept.
Those responsible for medical and environmental radiation are authorized to grant permits, to supervise over the implementation of the regulations and to recommend safety standards. They are advised by an expert committee, composed of representatives of the Ministry of Health and the Ministry of the Environment.
Supervision over Radioactive Isotopes
Work with radioactive materials can pose a grave risk to those who handle them, to the general population and to the environment. To reduce this risk, international standards were established and adopted in Israel as a basis for regulations and as guidelines for policy. The Ministry of the Environment is responsible for the granting of permits to users of radioactive elements in the civil sector, and its radiation inspectors carry out inspections in all radiation facilities over 300 institutions employing about 8000 workers with about 3000 installations.
The ministry’s radiation division is responsible for supervision of radioactive materials and facilities and of radioactive waste; monitoring of environmental radiation by means of a monitoring network comprising five stations; and risk assessment of environmental radiation from radon.
Israel’s primary concern in the management of low-level radioactive waste
(radwaste), produced by hospitals, research laboratories and institutions, and industrial and agricultural premises, is population safety and environmental protection. During the course of work with radioactive isotopes, a variety of materials from rubber gloves to equipment parts become contaminated and require safe disposal.
The authority for radwaste management in Israel is the radiation officer appointed by the Minister of the Environment under the Pharmacists Regulations on radioactive elements. The regulations authorize the officer to issue a license for waste disposal services, after consulting with the Israeli Atomic Energy Commission.
Each radwaste-producing facility in Israel is required to obtain a license for its operation. The license limits the amount of radioactive material purchased by the institute and approves the nomination of an internal radiation official responsible for the appropriate handling of radwaste inside the institute.
The Nuclear Research Center in the Negev operates and monitors Israel’s only national disposal site for radioactive waste. With regard to short-lived radioisotopes, the disposal of the waste to a regular municipal site is permitted provided the activity is reduced to a level below 74 Bq per gram (0.002 mCi/gram).
The Ministry of the Environment operates a computerized database management system on radioactive materials, with data on licensing, import and distribution, waste disposal and transportation. The waste disposal module of the database system will soon include a theoretical model for the estimation of the volume of radwaste production by large institutions necessary in order to validate the reports on quantities of waste produced by large users of radioactive materials.
Supervision over the disposal of radioactive waste has deepened recently, and a report was prepared based on the number of drums containing radioactive waste which were transferred from all institutions in Israel to the national disposal site in the Negev. Within the framework of the advisory committee on radiation, a report on waste disposal and treatment procedures was also prepared.
Public awareness of the problems associated with radioactive radiation grew in the aftermath of the Chernobyl disaster in 1986. Recognition of the need for routine assessments of background radiation levels led to the establishment of the first monitoring stations in 1987. Today, five radiation monitoring stations operate in Israel located in Haifa, Tel Aviv, Jerusalem and the Negev. The most recent station was established in April 1994 in Dimona, adjacent to the Nuclear Research Center. The establishment of the monitoring station at this site is an integral part of the ministry’s policy of freely providing environmental information to the public. Information from all of the stations is relayed, in real-time, to the central control station of the Ministry of the Environment. Each station has the capability of real-time alert to a beeper and the control center, which operates on a 24-hour-a-day basis.
In addition to these monitoring activities, the Ministry of the Environment conducts a representative random sampling of produce seasonal vegetables, fruits, milk and meat in three areas of the country, as well as testing water samples derived from the National Water Carrier. Samples of food, settling dust and suspended dust are analyzed using gamma-ray spectrometry.
The radiation division of the Ministry of the Environment has recently begun to collect soil, flora and water samples up to the fenceline of Israel’s nuclear research centers and is currently preparing to broaden its supervision over nuclear ships anchored in Israel’s ports.
Still another important function of the division is supervision over natural radiation including radon. The ministry has prepared guidelines for citizens on radon exposure explaining the health hazards associated with radon, defining the types of structures which are likely to be exposed to radon, and providing information on measurement methods and on authorized commercial companies dealing with radon monitoring. Radon surveys have been conducted in various parts of the country and the ministry has assisted a number of bodies, especially local authorities, in carrying out and analyzing the results of radon exposure risks, especially in educational institutes.
The authorized radiation officer is responsible for the grant of permits for radon inspection to commercial companies, according to criteria and conditions established by the professional staff of the radiation division. Results of measurements conducted by private companies are transferred to the Ministry of the Environment to facilitate the development of a database on radon concentrations in Israel.
As part of a continuing program of monitoring natural radiation in the environment, radiocesium distribution in the nearshore eastern Mediterranean Sea is being studied. A preliminary report on radiocesium isotopes in marine sediments from Haifa Bay in northern Israel and Iskanderun Bay in southeast Turkey was recently published. The samples investigated in this study comprise the top two centimeters of the sea-bottom sediments, sampled by box corer and analyzed by gamma-ray spectrometry. The spectrometric data obtained from fifty samples show the presence of a long-lived isotope of cesium, 137Cs, in all samples, but the presence of a short-lived isotope of cesium, 134Cs, in only fifteen samples.
These data could be useful in determining the magnitude of Chernobyl-related contamination in the region since the short-lived 134Cs
(2.06 year half-life) is identified with this event. The data could also be useful for estimating the rate of land denudation and weathering, and the behavior of radiocesium as a new contaminant factor in the marine environment.
Public awareness of exposure to radio wave radiation from different sources has grown dramatically in recent years mostly as a result of plans (now canceled) for the establishment of a Voice of America transmission station in the Aravah region which raised fears of excessive electromagnetic radiation.
Since no standard restricting population exposure to radio waves exists in Israel, the Ministry of the Environment has published a policy paper on the subject, based on the standard set by the International Radiation Protection Association (IRPA), recognized as one of the most stringent standards worldwide. The radiation flux density permitted according to IRPA is determined to be 1/50 of the density flux which might be manifested in health effects.
In order to set guidelines which enable the existence of a technological society, on the one hand, and provide for maximum population protection, on the other hand, it has been decided to adopt the ALARA principle (As Low as Reasonably Achievable) and to restrict new facilities emitting radio waves to 1/3 of the IRPA standard and existing facilities to 2/3 of the IRPA standard.
In addition, the ministry has been involved in restricting exposure to electrical and magnetic fields in the network frequency from high voltage lines and transformer stations. In this case, the IRPA standard has been adopted, restricting public exposure to electromagnetic fields in the network frequency for 24 hours a day to 1000 mG and to 5KV/m, accordingly. The ministry provides the district offices with guidelines and environmental opinions on the radiation safety of existing and planned facilities, which may cause significant electromagnetic fields in their environs.
The ministry also supervises companies which monitor microwave radiation, both for home microwave ovens and in radar and communication systems. The supervision is aimed at ensuring a high professional level, reliable service to the public and data collection to enable identification of sites with potentially dangerous radiation levels.
Finally, in light of growing concern over the adverse biological effects of ultraviolet radiation (UV), the ministry has prepared standards and procedures on equipment emitting such radiation. All artificial sources of UV radiation (with emissions in the range of 200-400 nm) which are designated for cosmetic tanning and/or medical treatment (phototherapy) must be registered. Detailed safety procedures with regard to ultraviolet radiation from tanning facilities were published, requiring, inter alia, that the cumulative yearly dose does not exceed the 50 minimal erythema dose (MED).
Legal Framework for Radiation Protection
The Pharmacists Regulations on radioactive elements and their products, under the authority of the Ministry of Health and the Ministry of the Environment prohibit the purchase, distribution, transportation and application of radioactive materials, except under a license. The regulations specify the conditions under which a license is to be granted, including basic facility and equipment requirements, such as floor and working surface coatings, washing facilities, sewage, ventilation and shielding arrangements.
Draft regulation on the disposal of radioactive waste from research institutes, hospitals, medical laboratories and other institutions are being prepared. They will include instructions on the disposal of solid and liquid radioactive waste as well as radioactive gases or vapors.
Regulations regarding the medical application of radiation machines, under the authority of the Ministry of Health, require the registration of radiation machines intended for diagnosis and/or therapy.
Safety at Work Regulations (Persons Engaged in Ionizing Radiation) are enforced under the authority of the Ministry of Labor and Welfare. They set guidelines for control in facilities where employees handle radioactive materials or radiation equipment.