Breastfeeding in the Face of Natural Disaster and Nuclear Reactor Core Damage

It has been well over a week now that we the citizens of the world have been watching the seemingly unending horror unfold in Japan.  First they endured an earthquake of historic proportions, followed rapidly by a tsunami of untold destruction.   These unexpected natural disasters are frightening, devastating, and so very poignant and sad to comprehend. One cannot live in this age of instantaneous video reporting and see those images of death and destruction and not be affected at some deeply primal and emotional level.  Initially, the concerns for after effects in other nations around the Pacific were also frightening, but came nowhere near the complete devastation in Japan.  Totally coincidentally, I have been working on the United States Breastfeeding Committee Position Statement on Infant/Young Child Feeding in Emergencies. The images on the television brought the horrors of Hurricanes Katrina and Rita here in the US vividly back to my mind, and the words I have been typing into my computer drafting the Position Statement seem so inadequate in the face of the reality I see on the television screen.   It leaves me feeling impotent to really help, armed only with a computer and words.

And then, as if it could not have gotten any worse, one day later, an explosion occurred at the damaged Fukushima 1 nuclear power plant initiating a radiation leak, making this a catastrophe of unprecedented proportion.  By 6 days after the explosion, Japan’s nuclear safety agency raised the severity rating of the country’s nuclear crisis from Level 4 to Level 5 on a seven-level international scale, putting it on par with the Three Mile Island accident in Pennsylvania, USA in 1979.  For comparison, the Chernobyl accident of 1986, which killed at least 31 people with radiation sickness, raised long-term cancer rates, and spewed radiation for hundreds of kilometers, was ranked a Level 7.

So why am I writing this on a blog for ABM?  Besides the humanity that connects us all globally, and the immediate questions that arose in the medical and lactation communities concerning humanitarian efforts and safe infant and child feeding practices on the heels of the earthquake and tsunami, (on which there is much already written) the radiation leaks have led to many questions and some incorrect information related to breastfeeding that it is important to address, for now and should we ever need to deal with this again.

To understand when breastfeeding in this situation is safe and preferred, one must understand some basic nuclear reactor radiation physics and biology.  When a leak or explosion occurs at a nuclear reactor site, ionizing radiation, which is unstable atoms that discharge energy to reach stability, is released.  It can be in two forms—electromagnetic and particulate.  Radionuclides, which are elements that emit ionizing radiation, exist both naturally (e.g., uranium) or can be manmade (e.g. plutonium).  There are 5 types of ionizing radiation.  The γ-rays and x-rays have no mass and are highly penetrating.  Neutrons are highly destructive, but very rare, only released after a nuclear detonation.  The α- and β-particles are heavy and in addition to landing on skin and clothing, can be inhaled or ingested and cause internal damage.  So radiation exposure can be divided into external, internal, whole body, or partial body. Internal irradiation can occur after inhalation of a radioactive gas or ingestion of contaminated food (including produce, grains, and milk from goats or cows that have been grazing on contaminated fields)¹ or human mothers’ milk or water. The health effects of these types of radiation can be anything from immediate radiation burns to long-term cancers.

In the event of a nuclear reactor meltdown as occurred in Japan, once out of the closest zone where radiation burns and immediate life-threatening effects occur, the concern is the ingestion in food or water or inhalation of particulate radiation, most often radioactive iodine.  Children are particularly vulnerable, as the “heavy” particles rapidly fall to the ground, settling in the area where babies and small children “live”.  Children also have a higher minute ventilation than adults, so they are at higher risk of breathing in more of the aerosolized particles.  And, iodine, including radioactive iodine is actively transferred into mammalian milk, both human and bovine, making two main sources of nutrition—human milk for infants and young children, and cow’s milk for older children if it comes from local areas where grazing fields have been contaminated, potential risks for this vulnerable population.  If contaminated water is used to mix formula for babies or ingested by itself, it serves as another source for internal radiation exposure.

Key to the response to a nuclear reactor meltdown are the concepts of evacuation, sheltering, and control of contaminated foodstuffs.  Just removing clothing worn during the exposure can reduce the external contamination by as much as 90%.  Surface decontamination also includes scrubbing with soap and water.  Evacuation is a decision made by local officials based on many different factors in an individual situation.  Sheltering can be accomplished by removing people from the environment and into intact structures.   For example, the shielding factor (the ratio of dose received inside the structure to the dose which would be received if the structure were not in place) for γ-rays after a radioactive cloud release is 0.9 for a wooden frame structure, 0.6 for a home basement, 0.4 for the basement of a masonry home, and 0.2 for a large office or industrial building.¹

The concern for internal contamination is radioactive iodine.  Whether it is absorbed via the lungs or ingested in the GI tract, it will be rapidly taken up into the thyroid gland.  Short term it can destroy the thyroid; longer term it can cause thyroid cancer.  Taking potassium iodide (KI) can protect individuals from radioactive iodine because it blocks radioactive iodine from being absorbed by the thyroid gland.  If KI is taken and the thyroid gland becomes saturated with it, no more radioactive iodine or KI can be absorbed for the next 24 hours.  But there is clearly a critical time period for taking the KI.  Best is before the exposure if that luxury exists.  Next best is immediately after the exposure; by 12 hours after exposure there is little protective effect.¹

There is no confusion about using potassium iodide in this circumstance.  The confusion seems to occur with whether breastfeeding women should breastfeed their babies.  All sources agree that the lactating woman should receive KI; all sources agree that the breastfeeding baby (as well as the non-breastfeeding baby and all other exposed children and adults) should receive KI, and as quickly as possible, once that recommendation is made by authorities.  It is suggested that KI be kept within certain radii of nuclear power plants particularly in hospitals, day care centers, schools, and other places where in particular babies and children will be, for rapid distribution should disaster strike.  The controversy comes with whether breastfeeding women should breastfeed or not.  I have read many scientific papers, government and organizational websites, and position papers, and I will attempt to briefly summarize what I have learned.

An example of the confusion is the difference in advice offered by two different organizations within the United States government—the Center for Disease Control (CDC) and the Food and Drug Administration (FDA).  The CDC has a web page on the use of potassium iodide in a radiological or nuclear event, which has been widely cited and quoted since the Fukushima 1 nuclear power plant radiation leak.   Its advice on breastfeeding is: “Because radioactive iodine quickly gets into breast milk, CDC recommends that women internally contaminated with (or are likely to be internally contaminated with) radioactive iodine stop breastfeeding and feed their child/ baby formula or other food if it is available. If breast milk is the only food available for an infant, nursing should continue.

This is in contrast to what other sources say, such as the FDA:  (page 7): “Lactating females should be administered KI for their own protection, as for other young adults, and potentially to reduce the radioiodine content of the breast milk, but not as a means to deliver KI to infants, who should get their KI directly. As for direct administration of KI, stable iodine as a component of breast milk may also pose a risk of hypothyroidism in nursing neonates. Therefore, repeat dosing with KI should be avoided in the lactating mother, except during continuing severe contamination. If repeat dosing of the mother is necessary, the nursing neonate should be monitored as recommended above. (I added: for thyroid function)”   These statements imply mother is treated, nursing infant is treated, and baby continues to nurse.

As you know, Dr. Ruth Lawrence, an esteemed ABM Founder and past-President, is not only the breastfeeding expert, but a toxicology expert as well. She addressed these issues on the ABM list serve last week, where a lot of questions and information were going back and forth.  Here is what she wrote:

“ May I jump in?  The discussion about potassium iodide is very important.  Iodides are one of the few compounds that are pumped into breast milk so that levels are much higher in milk than maternal serum.  Recommendations for KI should not be confused with radioactive iodine used diagnostically or therapeutically as the CDC seems to have done on their site.  If it is indicated that the mother should take KI she can do so even if she is breastfeeding.  The baby should continue to breastfeed.  The infant can receive one dose calculated to its weight.  Breastfeeding should continue.   Ruth Lawrence”

As Dr. Lawrence points out, another point of confusion is the use of the recommendations against breastfeeding when radioactive iodine (I-123 or I-131) is used either diagnostically or therapeutically. We all know that the safest, indeed life-saving food for babies and young children in a disaster the magnitude of that in Japan is breastfeeding/ breastmilk.  It would be another disaster for babies to be denied breastmilk because of misinformation.  But I believe that part of the confusion resides in the circumstance of radioactive iodine fallout with no potassium iodide available.  In this particular case,  suspension of breastfeeding would minimize the amount of radioactive iodine ingested (but would not affect what is inhaled) by nursing infants.  Remember both ingested and inhaled radioactive iodine will end up in the thyroid gland.  IF a safe alternative food source is readily available and KI is not, a mother might be counseled to feed her baby the safe food source until the baby is treated with KI to protect its thyroid from any radioactive iodine in the mother’s milk.  But under disaster circumstances with no safe food alternative food source, that might be a big if. And remember, local water is contaminated as well, so if we are talking formula, the formula and the water to mix it, unless it is ready to feed, would both have to be  uncontaminated (i.e. in closed containers).

“The protective effect of KI lasts approximately 24 hours. For optimal prophylaxis, KI should therefore be dosed daily, until a risk of significant exposure to radioiodines by either inhalation or ingestion no longer exists. Individuals intolerant of KI at protective doses, and neonates, pregnant and lactating women (in whom repeat administration of KI raises particular safety issues, (see next) should be given priority with regard to other protective measures (i.e., sheltering, evacuation, and control of the food supply).”²  Repeat dosing of KI should be avoided in the neonate to minimize the risk of hypothyroidism during that critical phase of brain development.²

KI is not a panacea treatment for radioisotope contamination. It cannot prevent uptake of any other radioisotopes than iodine. It cannot prevent any radioisotopes, including radioactive iodine, from entering the body, and once present in the body, KI can only act to prevent the radioisotope from entering the thyroid gland. Once radioactive iodine has entered the thyroid, KI cannot remove it, or reverse the health effects caused by it. The use of KI is also limited to a narrow time frame of effectiveness. If taken more than 4 to 6 hours after internal contamination with radioactive iodine has occurred, radioiodine will have already saturated the thyroid gland, and stable iodine, in the form of KI, will be ineffective as a countermeasure.

A life-long friend of mine, who travels frequently for his business and is not generally given to sentimentality, wrote to me after the disaster in Japan occurred.  “The Japanese are the most gentle, polite and respectful people I’ve ever met after travels around the world. They did nothing to deserve an earthquake, tsunami and now triple play nuclear meltdown…” (quoted with permission).

I hope this long discussion has helped you understand the issues of nuclear reactor radiation leaks as they relate to radioactive iodine and breastfeeding.  Let’s keep the people and Country of Japan in our thoughts and prayers as they continue to go through this terrible time, and offer them any help and support we can.  And to our ABM colleagues there, know we are with you…

References

1.  American Academy of Pediatrics.  Policy Statement Committee on Environmental Health.  Radiation Disasters and Children.  Pediatrics 2003;111(6):1455-1466.
2. Guidance.  Potassium Iodide as a Thyroid Blocking Agent in Radiation Emergencies.  U.S. Department of Health and Human Services Food and Drug Administration Center for Drug Evaluation and Research (CDER); December 2001.  http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/ucm080542.pdf last accessed 3/22/11

Other on-line references:

http://www.lef.org/magazine/mag2007/oct2007_report_potassium_iodide_01.htm

http://www.fda.gov/Drugs/EmergencyPreparedness/BioterrorismandDrugPreparedness/ucm072265.htm

http://emergency.cdc.gov/radiation/index.asp

http://en.wikipedia.org/wiki/Fukushima_I_nuclear_accidents (includes many links to news articles and other reports on a day-by-day basis)

Kathleen Marinelli MD, IBCLC, FABM is a neonatologist a Board member of the Academy of Breastfeeding Medicine, and Chair of the ABM Protocol Committee.

Posts on this blog reflect the opinions of individual ABM members, not the organization as a whole.