Study links occupational exposures to radiation in veterinary medicine with risk of miscarriage.

A recent study from Australia identified a correlation between veterinarians who have occupational exposures to anesthetic gasses, radiation or pesticides. These veterinarians may have twice the risk of miscarriage (1). This study confirms the findings of previous studies(2,3) that also found a link between occupational radiation exposure and miscarriage among veterinary personnel.

The authors of the Australian study found that there was a significant risk of miscarriage when veterinarians perform five or more radiographic examinations per week during pregnancy.

The AVMA position on veterinary facility occupational risks for pregnant workers(4)states that pregnant workers should avoid exposure to x-rays. It is not unreasonable, therefore, that pregnant workers in the veterinary hospital should aim to avoid radiography during pregnancy once the pregnancy is known.

The real issue with any discussion of pregnant veterinary workers is that, in many cases, the pregnancy is not known until after exposure to the fetus. If the normal radiation safety measures are taken, the exposure to the fetus should still be below the NRC recommendations for fetal exposure. Unfortunately, conformance with the recommended radiation safety protocols among veterinary technical staff is often times poor (5).

Another area of concern with respect to technician and veterinarian radiation safety is the fact that some digital radiography machines have HIGHER exposures than film radiography (6). Some digital radiography systems marketed to the veterinary profession may require a four fold increase in exposure when compared to film radiography.

All veterinary technicians should be advised that the fetus is more sensitive to radiation and instructed on prudent radiation safety practices. These include decreasing time in radiology, increasing the distance to the radiation source during radiography, and utilizing proper radiographic shielding (gloves, aprons, etc).

Once a pregnancy is known, the pregnant technician or veterinarian should be given the option not to perform radiography. Additionally, the staff member should be given a copy of the United Stated Nuclear Regulatory Commission (NRC) Regulatory Guide 8.13 - Instruction Concerning Prenatal Radiation Exposure.

If a staff member must continue to work in radiology.

• The technician is given two radiation monitoring badges. One badge is worn on the torso and the other badge worn over the abdomen.
• The badges must be submitted for evaluation on a monthly basis.
• Exposures must be less than 50mrem per month during the pregnancy.
• The monthly reports should be reviewed with the DPW and these reports should become part of the workers permanent dose history.
• Contact your local or state radiation safety officer to make sure that you have taken all of the proper precautions.

References:

• http://oem.bmj.com/cgi/content/abstract/oem.2007.035246v1
• Int J Occup Environ Health. 1996 Jan;2(1):26-36.
• http://aje.oxfordjournals.org/cgi/content/abstract/132/1/96
• AVMA Position on Veterinary Facility Occupational Risks for Pregnant Workers http://www.avma.org/issues/policy/pregnant_workers.asp
• authors personal observation based on experiences at dozens of veterinary hospitals and countless radiographs with images of unprotected human fingers restraining animals.
• results of the Annual Veterinary Digital Radiography SHOWDOWN andVeterinary DICOM Validation