§ Mr. LivseyTo ask the Secretary of State for Health what research his Department has undertaken on whether persorption and translocation expose certain subgroups of the population to increased radiation doses. [100861]
§ Yvette Cooper[holding answer 2 December 1999]: The Department has funded, and continues to fund, research into the phenomenon of persorption (absorption 440W of particulate material through the gut wall). This research has demonstrated that particulate material can be persorped and translocated in some animal models under very specific biological conditions. However, further work is required to determine whether this would increase the dose to those tissues affected.
§ Mr. LivseyTo ask the Secretary of State for Health what research his Department has undertaken into the risks associated with ingestion and inhalation of radioactive particles. [100854]
§ Yvette Cooper[holding answer 2 December 1999]: The National Radiological Protection Board (NRPB) has a comprehensive programme of research on the biokinetics and dosimetry of inhaled particles, including human studies of particle deposition and clearance and animal studies of particle dissolution in the lung. Complementary studies on ingested particles have also been undertaken. These studies have the aim of improving estimates of dose and risk by providing information for the development of biokinetic and dosimetric models. In recent years, many of these studies have been carried out with partial support from the European Commission in multi-partner projects involving institutions in several member states. The NRPB has recently participated in a review of risks from ingested and inhaled particles, and in the development of a database of experiments on radionuclide biokinetics, undertaken for the European Late Effects Programme funded by the European Commission. The Department has also funded studies on the behaviour and effects of inhaled and systemically administered radioactive particles.
§ Mr. LivseyTo ask the Secretary of State for Health what research his Department has undertaken on methods for assessing the relative biological effectiveness of Auger-emitting radionuclides. [100858]
§ Yvette Cooper[holding answer 2 December 1999]: The National Radiation Protection Board has undertaken studies of the biokinetics, dosimetry and relative biological effectiveness (RBE) of the Auger-emitting nuclide, zinc-65. The method used to compare the RBE of zinc-65 and x-rays was to measure chromosome damage in cultured prostate cells either incubated with zinc-65 or exposed to x-rays. The NRPB has recently contributed to a review of data on Auger-emitting nuclides, undertaken for the European Late Effects Programme, funded by the European Commission. The Department is also currently funding research into the effects of Auger emitters which is not yet complete.
§ Mr. LivseyTo ask the Secretary of State for Health what representations he has received about the risks from low doses and low dose rates of ionising radiation; and what research his Department is(a) undertaking and (b) has commissioned on this subject. [100841]
§ Yvette Cooper[holding answer 2 December 1999]: Since 1986, the Department and its predecessor, the Department of Health and Social Security, has administered the Radiological Protection Research Programme. The objective of this programme is to identify the research which is needed to inform policy development in the area of low level radiation exposure (both ionising and non-ionising), its effects, and the need 441W to quantify the risk to public health and to implement appropriate preventative measures. The programme has funded many individual research projects designed to examine these aspects of radiation exposure. During that 14-year period, the Department has had a considerable number of representations on the effects of low level radiation exposure from both individuals and groups representing a large variety of environmental concerns.
§ Mr. LivseyTo ask the Secretary of State for Health if his Department will commission research into the health effects of(a) ingested and (b) inhaled uranium as a result of exposure to ammunition containing depleted uranium. [100842]
§ Yvette CooperThe Department has not commissioned any research into the effects of exposure to depleted uranium and has no plans to do so.
§ Mr. LivseyTo ask the Secretary of State for Health what epidemiological research his Department has(a) undertaken and (b) commissioned into the health effects of aqueous and atmospheric discharges of radioactive isotopes from licensed nuclear sites in England and Wales. [100843]
§ Yvette Cooper[holding answer 2 December 1999]: The Department is funding a project entitled "Geographical variations in childhood cancer incidence generally and in relation to nuclear installations." The contract is held by the Childhood Cancer Research Group in Oxford but is a multi-centre collaboration so that all cases of childhood cancer in Great Britain (England, Scotland and Wales) between 1969 and 1993 can be included in the study. The study will be looking at variations in incidence rate in relation to socio-demographic factors, clustering, population mixing, nuclear installations and parental preconceptual irradiation.
§ Mr. LivseyTo ask the Secretary of State for Health what research his Department has undertaken on the relationship between the chemical form of specific radionuclides and their localisation in the body. [100860]
§ Yvette Cooper[holding answer 2 December 1999]: The Department has funded research into whether the chemical form (speciation) of particular radionuclides effects their uptake. Currently, the Department is funding a study of the gastro-intestinal uptake by critical populations of certain radionuclides found in the general environment, such as strontium. The results, when available, will be used to test the validity of uptake models.
§ Mr. LivseyTo ask the Secretary of State for Health how the radiation dose from plutonium incorporated in tracheo-bronchial lymph nodes is determined. [100853]
§ Yvette Cooper[holding answer 2 December 1999]: There are two methods that are currently in widespread use by the radiation protection profession around the world. Both were developed by the International Commission on Radiological Protection (ICRP). The first is the ICRP 30 Lung Model, the second the ICRP Human Respiratory Tract Model for Radiological Protection (HRTM). The approaches in both are broadly similar to each other, but HRTM is based on more recent 442W information and understanding. In particular, the parameters used in the HRTM to calculate the amounts of inhaled materials retained in the tracheobronchial lymph nodes (TBLN) were based on numerous measurements of radionuclides in lungs and TBLN from tissues taken at autopsies.
§ Mr. LivseyTo ask the Secretary of State for Health what research his Department has undertaken to establish whether plutonium isotopes concentrate in human gonads. [100856]
§ Yvette Cooper[holding answer 2 December 1999]: The Department has funded research to establish whether plutonium concentrates in human gonads. The project, using extremely low levels of a very pure form of plutonium-237 in volunteers, demonstrated that plutonium does not concentrate in human testes.
§ Mr. LivseyTo ask the Secretary of State for Health what research his Department has undertaken into whether radionuclides concentrate in human gonads. [100855]
§ Yvette Cooper[holding answer 2 December 1999]: The Department relies on advice on this matter from the National Radiological Protection Board (NRPB). As part of a programme of research on the biokinetics and dosimetry of radionuclides, NRPB have measured the retention of radionuclides in the testes of rodents and, in collaboration with the Paterson Institute for Cancer Research, studied mechanisms of uptake. Work has concentrated on the behaviour of naturally occurring and artificial alpha emitters and also Auger emitters, because of the importance of the relative position of the retained nuclide and target cells for these short range emissions. Most radionuclides do not concentrate selectively in the gonads. The NRPB' s Assessment of Internal Doses to Subjects in the Health and Safety Executive Follow-up to Gardner Study involved calculating doses to testes from incorporated radionuclides for a group of Sellafield workers. As a part of this project, information relating to radionuclide retention in the testes was reviewed. Particular attention was paid to plutonium. From the data available, it was found that only between one thousandth and one ten thousandth part of the plutonium taken up by the body ended up in the testes.
§ Mr. LivseyTo ask the Secretary of State for Health what research his Department has undertaken on the interaction between ionising radiation and other environmental agents. [100857]
§ Yvette CooperThe Department has funded research in an attempt to examine the interaction between ionising radiation and other environmental agents, specifically the interaction between gamma rays and benzene. These experiments proved very difficult to perform in realistic biological systems and the results were inconclusive. Further information on the mechanisms of interaction between radiation and other environmental agents remains a priority for research.
§ Mr. LivseyTo ask the Secretary of State for Health what research his Department has undertaken on methods for assessing the relative biological effectiveness of natural alpha-emitting radioisotopes. [100859]
§ Yvette Cooper[holding answer 2 December 1999]: The National Radiation Protection Board has undertaken experimental studies of the biokinetics and dosimetry of 443W naturally-occurring alpha-emitting radioisotopes of thorium, uranium and polonium, with the aim of improving estimates of dose and risk from exposure to these radionuclides. An NRPB study of the relative biological effectiveness (RBE) of in-utero exposure of mice to plutonium-239 alpha emissions, chromosome damage in bone marrow cells of offspring was compared in animals exposed to either plutonium-239 or x-rays. This methodology is applicable to naturally occurring alpha-emitting nuclides and avoids large-scale studies of tumour induction. The Department is also funding studies in animals on the effects of inhaled radon. These studies, concentrating on dose and dose rate effects in the induction of lung cancer, will provide information for the assessment of RBE.