workers, building, architect

NORA Manufacturing Sector Strategic Goals

927ZBCK – Occupational Electromagnetic Fields (EMF) and Brain Cancer

Start Date: 10/1/2007
End Date: 9/30/2010

Principal Investigator (PI)

Name: Joseph Bowman
Phone: 513-841-4127
Organization: NIOSH
Sub-Unit: DART
Funded By: CDC Foundation and National Institute of Health

Primary Goal Addressed


Secondary Goal Addressed


Attributed to Manufacturing


Project Description

Short Summary

This project examines whether occupational exposure to electric and magnetic fields (EMF) in combination with selected chemicals are risk factors for brain cancer. Funded by a three-year NIH grant, this research will be performed with data collected by the INTERPHONE study of cellular telephones, the largest case-control study of brain cancer ever conducted. Interview data collected in eight countries will be combined with job-exposure matrices for EMF and chemicals. The analysis will test whether the chemicals and EMF in each frequency band increase the risks of brain cancer, either independently or synergistically. The results will be used to evaluate the carcinogenicity of EMF, either from existing occupational sources or new wireless devices. NIOSH has also been invited to advise on EMF exposure assessment methods for Dutch epidemiologic studies.


The INTERPHONE study was a multi-national prospective case-control study of cellular telephones and cancer risk coordinated by International Agency for Research on Cancer (IARC). It was conducted in 13 countries using a common core protocol, and focused on the risk of glioma, meningioma, acoustic neurinoma and salivary gland tumors. A total of 2,613 glioma and 2,343 meningioma cases and 7,557 controls were recruited between 2000 and 2005, making INTERPHONE the largest epidemiological study of brain cancer ever conducted.

This new study called INTEROCC aims to exploit the occupational exposure data collected by the INTERPHONE study. It has three specific aims:

1. To evaluate the possible association between the occupational EMF exposure and tumors of the brain and central nervous system (specifically, glioma and meningioma).

2. To evaluate the possible association between selected occupational chemical exposures and tumors of the brain and central nervous system.

3. To investigate the possibility of synergism and/or confounding between chemical and EMF exposures on the risk of brain cancers.

In order to achieve these substantive aims, INTEROCC will address the following operational objectives:

• To transform the occupational history and questionnaire data into meaningful indices of EMF.

• To devise and implement methods for transforming job histories into occupational chemical exposure information.

Occupational exposure to EMF (both ELF and RF) and selected chemicals will be assessed for all the study subjects using validated job-exposure matrices (JEM), which will be developed within this project. Finally, analyses of the relationship between brain tumor risk and exposure to EMF and to the chemicals of interest will be carried out. Further analyses of possible interactions between EMF and specific chemicals will also be conducted. This study is funded by an R01 grant from the National Institutes of Health.

A detailed protocol was developed by a meeting of all INTEROCC investigators. Dr. Elisabeth Cardis in CREAL is responsible for study coordination and the statistical analysis. The study centers in the participating countries are responsible for coding the occupations and industries of their subjects. Development of the chemical JEMs is coordinated by the industrial hygienist David McLean and Martie von Tongerin. Dr. Bowman provides the JEM for ELF magnetic fields and coordinates the development of the EMF exposure assessment algorithm. He is assisted by CREAL contractors David Conover and Leslie Richardson, plus a research assistant from the University of Cincinnati.

For the Dutch EMF&H program, Dr. Bowman is collaborating with Prof. Hans Kromhout of the University of Utrecht on a grant application to the Dutch government. If the grant is approved, Dr. Bowman will spend 1 – 2 weeks per year in Utrecht, consulting on study design and teaching exposure assessment methods.


This project will collect data on citations of the study’s publications by other research studies and by authoritative public information documents and risk evaluations.

Mission Relevance

This project examines workplace risk factors for brain cancer with data collected by the INTERPHONE cellular telephone study, the largest case-control study of brain cancer ever conducted. The INTERPHONE interviews collected detailed information on the subjects’ employment history and occupational exposures to electromagnetic fields (EMF) in the extremely low frequency (ELF) and radio-frequency (RF) bands.

It is important to discover whether EMF is an occupational carcinogen for several reasons. Recent years have seen an unprecedented increase in the number and diversity of EMF sources. Such sources include television, radio, computers, mobile telephones, microwave ovens, radars and equipment used in industry, medicine and commerce. In the U.S., 25,000,000 workers are exposed to EMF at levels associated with increased cancer rates in epidemiologic studies. Over 7 million workers are exposed to RF communication sources, including radio and TV transmitters and cellular telephone base stations, in addition to millions of workers who are required to use telecommunications equipment. As many new EMF technologies are being introduced, any potential for increased cancer risk associated with such technologies needs to be identified as soon as possible. If EMF exposures cause cancer, either alone or in combination with chemicals, the potential public and occupational health impact could be large. It is therefore important that every attempt be made to identify possible health risks associated with EMF exposure in different frequency ranges. Brain tumors affect a younger population than most other tumors, and the years of life saved by prevention of these tumors is significant.

A new addition to this project is possible collaboration with the Dutch National Program on EMF and Health (EMF&H). EMF&H has begun several epidemiologic studies of RF and ELF fields in the environment and workplaces. Dr. Bowman has been invited to be a visiting expert on exposure assessment for these studies, pending funding from the Dutch government.

Surveillance data shows that ELF and RF exposures occur in all sectors, especially the Service and Manufacturing sectors. This project addresses these NIOSH intermediate goals and activity/output goals:

Cancer, Reproductive, and Cardiovascular Disease Activity/Output Goal 1.1.5: Develop methods for quantitative cancer risk assessments, in support of authoritative recommendations for limiting occupational exposures.

Exposure Assessment Intermediate Goal 1.4: Develop strategies for the support of performance-based occupational exposure limit approaches such as control banding.

Exposure Assessment Activity/Output 2.6.1: Completion of a new or improved method to measure or estimate levels of an important physical � occupational health stressor such as � non-ionizing radiation �. .

Page last reviewed: July 22, 2015