Wednesday, December 18, 2013

Can you help this pregnant woman?

A friend called to ask for help on an issue related to her pregnancy. Do you know anyone who might be able to provide advice? Here is the situation:
A bad termite infestation has been discovered in her apartment, as well as the other units in her block in San Franciso. The entire block of apartments will need to be tented and sealed while a pressurized gas called Vikane gas is pumped in over a period of 3 days to kill the termites. The active ingredient in the gas, which is supposed to be quite noxious, is sulfuryl flouride. All building occupants will have to vacate the premises for 3-4 days, taking all foodstuffs and clothing with them as the gas can contaminate those items. Apparently, the gas can also go into any fiber containing furniture items - mattresses, pillows, etc. Once it settles in these items, it can take 45 days to dissipate.

My friend is just at the end of her first trimester of pregnancy. She's concerned about whether the exposure to after-gas effects is likely to cause harm to her fetus. She's looked up whatever literature she can find, but there's not much of it, and it's inconclusive. The gas is sufficiently noxious that people who have gone into a treated area too soon have been sickened and/or died.

The manufacturer says this:

Will Vikane affect my pregnancy?

Your fumigator is required to test the air in your home using specialized equipment to ensure that the Vikane level is below the EPA requirement before allowing you to re-enter your home. The EPA requirement is 1 ppm or less in all breathing zones. At such a level, no fetal effects or long-term health effects would be expected.

That description does not give my friend enough precision or satisfaction.

So, the options she is considering are:
1) Move to a new place (the landlord will release them from the lease, but finding something new is a challenge. They prefer not to move at this time, but will do so if it is unsafe.
2) Remove all fiber furniture before the fumigation and put it into storage, then go back a week later.
3) ???

She'd love to understand the potential side effects and hazards of the Vikane gas a little better. Is there anyone reading this who might be able to help provide advice on the pregnancy or toxicity side of things?


adena said...

re-posting - contact Julia Brody at the Silent Spring Institute in Newton. She works in this area.

Anonymous said...

I have no technical knowledge, but try poison control number or local Hazmat number? They might at least hook her up with someone with the knowledge.


Nancy Thomas said...

Don't think I have ever quoted Donald Rumsfeld - but in this case:

"There are known knowns. These are things we know that we know. There are known unknowns. That is to say, there are things that we know we don't know. But there are also unknown unknowns. There are things we don't know we don't know."

Move! You also don't want to bring a newborn into this post-fumigation environment....

Elias Kass, ND, LM, CPM said...

The folks at OTIS Teratology can be very helpful --


clsmt said...

I would get a POD and move the furniture out. The peace of mind would be worth the money it would cost to move things.

Anonymous said...

If it were me, I'd want to play it safe and move. But that's a huge hassle. And your friend also needs to understand that, consciously or subconsciously, she is elevating the risk higher than it is in actuality. That's a natural human tendency.

What about a variation of option 2, but wrapping the furniture in some relatively thick plastic? Bedding, pillows, etc. would go into trash bags (contractor grade = thicker) and could stay there or move out. Have a friend go back in the home, unwrap the furniture, open up the windows for 2-3 days, and then move back in with a relatively clear conscience, knowing that there's something yet to be discovered that's a greater risk than less than 1 ppm of Vikane.

Rick McClead MD Nationwide Children's Hosoital, Columbus Ohio said...

I asked our pharmacologist-toxicologist about this case. Here are his comments that I edited slightly.

"First, I refer every pregnant woman with concerns about chemical exposures to an OTIS call center (organization of teratology information services, or something like that) and if I have special concern myself, I choose the mother of all OTIS centers, MotheRisk in Toronto – headed by Gideon Koren who’s done more publishing in this area than anyone else. (1-877-439-2744 is their helpline, or – not only one R in there)

One of the things MotheRisk will do is let the patient know whether their center has any in-person experience with this poison during pregnancy, and how those pregnancies turned out. One of the things they’ll do is reassure Mom that, having finished the time when organogenesis occurs in first trimester, she’s already past the time when most teratogens could act anyway. And they’ll assess risk from the literature and help Mom decide among the options the blogger listed. Finally, they’ll likely ask Mom for permission to follow her case through a known conclusion – to see what sort of exposure she finally allows or refuses and to record baby’s health after delivery – to help future callers.

Second, since the manufacturer was the source of at least some of the data, the Tox fellows and I checked a few databases.

It’s really a nasty poison, causing death through several mechanisms (displaces oxygen; fluoride toxicity; hypocalcemia). Of the several authorities who announce safe levels, the lowest I found was 5 ppm, so the reported EPA safe level of 1ppm adds an extra measure of safety. A number of lab animal studies have been done to find teratogenicity; levels that are safe to the mother animal are safe to the baby with no teratogenesis reported.

We did find some studies showing fetal toxicity; the most concerning of these was a study that soaked animals for 10 weeks in 20 ppm, then allowed mating, then continued kept the animals in 20ppm until the babies had weaned; the only real trouble this causes was smaller fetal weight, and only due to the mothers being sick and not eating as much themselves. This isn’t teratogenicity; it’s maternal toxicity.

We also found how the EPA came up with 1 ppm. That really includes a safety factor of 100 for kids, and 500 for adults, and they chose 1ppm basically because it’s the lowest number a worker can get out of the best equipment for measuring air levels on site. In other words, it’s as low as they can measure, and way lower than any levels reported to cause any troubles in humans.

So the info the patient received looks legitimate.

If this were my wife and I, we’d want some confidence we got down to the 1 ppm level at all breathing zones (remembering mom’s spend a lot of time breathing just above the mattress), and we’d not worry further. If this were my patient and she still wasn’t satisfied, I’d suggest this might be a great time for a vacation, or maybe the landlord could wait a few months on the fumigation? Or go ahead and choose any of the other options the blogger listed, knowing these are all providing more work and even greater margins of safety."

A perinatologist said...

I love these easy questions! The critical features in discussing noxious chemicals in pregnancy is the teratogenic timing (5-11 weeks for malformations) and the dosage (in this case very uncertain but probably quite low at 1 ppm.). Since we don’t have exact information on either, I am afraid it would be impossible to any valid idea of fetal risk. Sounds like nasty stuff and if I were pregnant I would feel a bit jumpy myself at going back into a home recently fumigated. As far as science goes, 1part per million is pretty small and if they can guarantee her that level of contamination, the likelihood of fetal injury should be quite low. However, since this stuff works on the nervous system, and the nervous system evolves during the pregnancy (and beyond) there are going to be untestable concerns for a long time for fetuses or babies in this environment, which adds to the uncertainty. How’s that for a precise answer?

Lisa said...

In a previous job I had the responsibility for employee safety, air quality, hazardous materials, etc.

Advise your friend to get the actual Material Safety Data Sheet (MSDS) as we often overlook some of the other ingredients that may be harmful, especially to an unborn fetus. The entire chemical composition needs to be looked at. The MSDS will provide acute and chronic long term exposure hazards.

In addition, if I were your friend, I would ask my obstetrician to review the MSDS with consideration to where she is in her pregnancy. I’m thinking there may be an Industrial Hygienist in your distribution that will weigh in.

Robert Lewis said...

Obviously leaving for a period of time would be her best bet, but life isn't as easy as simply picking up and moving whenever you feel like it.

That's especially true in San Francisco where housing is at an absolute premium--studio apartments cost 1-2k per month or more to rent.

I certainly wouldn't trust the manufacturer with my child's health and well-being, or my own for that matter.

Barbara said...

If I were in your friend’s shoes, no explanation of the effects of the gas would be comforting or satisfactory. I would not hesitate to move…even though they “do not prefer to do so at this time.”

Anonymous said...

MSDS! That's what I was trying to think of. And Barbara, we often overestimate the risks of something new presented to us, while ignoring perhaps greater risks which have been in our environment all along. And who knows what may be or might have been in the new apartment.
I think one finds all the evidence possible and then makes the best decision based on that.
And btw, I sure like the new capcha (or whatever it is) numbers rather than those impossible letters.


Anonymous said...

If anyone is familiar with the rents and economics of present day San Francisco, they may begin to wonder if this is not a tactic to make them want to to move. It's not uncommon for renters to receive payouts of $40k or more (related to rent control and tenants rights).