Author reviewing project work.

As if crumbling foundations weren’t bad enough, along comes the coronavirus.  Well the good news is you can safely read the remainder of this post from the comfort of home, without a mask, and without again encountering the words coronavirus or Covid-19.    

But, before you start here’s a suggestion, read parts one and two about crumbling foundations to better understand the problem with failing concrete in north central Connecticut and south central Massachusetts.  Part one describes the discovery and investigation of my home’s failed foundation; and part two summarizes my experience seeking insurance coverage.  This third and final part is about the reconstruction process.

Now to start, I’ll note that people enjoy talking about improvements they make to their homes.  I certainly understand why.  They’ve installed new kitchens with state-of-the-art built-in appliances; bathrooms with glass walled showers; and welcoming entranceways with imported ceramic tile. We (Mrs. Okun and I) don’t talk about home improvements that way.   Instead we talk about the money we’ve put under our house.  Not because we had a vault with gold in the basement.  No.  It’s because removing and replacing our failed foundation exhausted any prospective home improvement funds and then some!

The Writing on the Walls

Recall from part one that on a trip to my basement in 2006 I discovered mysterious cracks had opened up in the concrete walls.  Soon enough we learned their meaning: “All those cracks in your basement walls? I don’t know exactly what caused them, but I can tell you with certainty that this concrete is toast and needs to be replaced, soon.”  So declared our structural engineer Rob Johnson PE. 

We were among the first of what would become many in north central Connecticut to lose our home’s foundation to bad concrete.  Later testing proved the failure was caused by the mineral pyrrhotite in the concrete.  But upon first discovery it just seemed like extraordinarily bad luck. 

Rob said we needed to immediately hire a contractor to install shoring to support two walls that were already bowing out badly and in the initial stage of collapse.  He sketched up plans for the shoring and told us to give them to the contractor.

This was in 2006, well before the crumbling foundation issue had received much visibility – except for the help we got from our experts, we were on our own.  At that time there were no contractors specializing in foundation replacements the way there are now.  However, thanks to working at OTO I had good contractor connections.  At the suggestion of OTO friend and construction manager, the late Richard Wilke, we hired Kurtz, Inc. of Westfield, MA to install the shoring per Rob’s plan and went on to use them to replace the basement walls, footings and the foundation drainage system. 

In the past few years, as the number of houses with crumbling foundations has grown, support groups have developed, and the state of Connecticut has set up a program to help homeowners pay for foundation replacements.  None of this existed when we were stumbling around trying to understand what was happening and planning what to do next.  We heard stories about a few other families with failed foundations, and tried to reach out to them.  Some were happy to talk about their experiences, but others were quite reluctant.  For them it was like having a disease that they did not want to talk about.

Construction Begins

As more homes and other buildings are found with crumbling foundations the demand for restoration services has grown.  There are now several excellent contractors who specialize in replacing crumbling foundations.  They’ve learned to optimize construction methods, which means getting work done faster and cheaper.  But, this didn’t exist when we did our replacement.  We were “early adopters” of foundation replacement technology, so we and our contractor needed to do on the job learning. 

One factor people overlook when planning foundation replacement work is that you can’t live in a house while the work is going on (figure on 2-4+ months).  In our case we needed to move out for 4.5 months.   All of the utilities need to be turned off and disconnected during the work making the house unlivable.  After we moved out, our contractor Kurtz obtained the building permit and began work by “sistering” all the joists in the basement in accordance with the engineer’s plan.  This meant attaching an additional joist next to all the original joists in the basement.  This added stability and strength to the structure to help it endure what came next.

Kurtz then cut holes through the existing foundation walls and installed big steel I-beams all the way through the basement to support the house.  The weight of the house was effectively now shared between the I-beams and the failing foundation.  A deep trench, resembling a medieval mote, was excavated all the way around the house.  All the soil removed from the trench became giant piles on our once carefully tended lawn. 

Rather than removing the old foundation and then constructing the new one all at once, Kurtz instead removed sections of the foundation and replaced each section one at a time moving methodically around the house.  Big piles of broken concrete now appeared next to the piles of soil on the lawn.  Kurtz also replaced the footings that supported the concrete walls and installed a new storm water drainage system around the house. 

Doorway to nowhere.

At my request, Kurtz installed some steel reinforcing bar into the new concrete walls.  Our engineer, Rob Johnson, told me the rebar was really unnecessary, but I thought I’d sleep better knowing it was there.  Of course we verified that the replacement concrete was from a completely different source than the old concrete.  As shocking as may seem, the supplier of our original concrete was still selling bad concrete batches for use in new homes and other buildings!  Sadly, there are even reported cases of homeowners replacing their bad foundations with concrete from that same bad source and having it fail again!  Now that is bad luck.

Post Construction Stuff

During any construction or renovation work some things inevitably happen that were not planned.  This seems to be as much a law of nature as gravity.  In a way we got off easy in that the only big surprises were the loss of the heating system due to frozen pipes in the boiler and the need to replace some of the clean water distribution piping and valves.  Well then there was also the outdoor lighting that was lost and needed to be replaced.  But overall not too bad.

During our original planning, the foundation of the attached garage looked only slightly deteriorated, so we did not include its replacement as part of the 2006 project.  However, be ten years later in 2016, it was looking much worse.  Since we planned to sell the house in the next few years, we eventually hired a contractor to replace the garage foundation, a similar, but simpler project than the house had been. It went smoothly.

In 2017 we finally did sell the Ellington house and as I walked out the door for the last time I vowed to never again own a house. This is a vow I kept until just this month.  The foundation walls of the “new” house (95 years old) are made of stone, and in addition the structure is supported by two really big steel I-beams.  During the home inspection I noted that one of these beams had a little rust.  When I asked him about it our home inspector told me not to worry, any possible harm from the rust was likely insignificant. 

Oh well, no matter how special the upstairs, my evaluation of a house will always begin in the basement where I can clearly see evidence of the foundation’s soundness

If you haven’t already read Part 1 of this mini-series, please do so before reading this post; what follows will make more sense.

But first, a rant on home owner’s insurance policies.  For your sake, I hope you never need your home owner’s insurance.  You know all those warm fuzzy ads on TV with clever bylines like: “You’re in good hands” or “We know a thing or two because we’ve seen a thing or two.” Yeah, well good luck with that, because if your foundation is crumbling and your house is starting to collapse, those good hands won’t be writing you any claims checks.  But the companies do come up with clever sales slogans and with creative reasons for denying claims.  And that’s what this post is about.

Discovering the Damage, My First Claim, and Rejection

As you recall from Part 1, on an otherwise normal trip to the basement of my Ellington, Connecticut home in 2005, I discovered the concrete walls were literally disintegrating; this may sound like an exaggeration, but it’s not.  Fortunately, working with a bunch of talented engineers at OTO got me going in the right direction.  My co-worker Mike Talbot, PE made an emergency house-call to my basement the next day.  His prognosis was not good.  “I’ve never seen anything like this before.  You better get Rob Johnson, a structural engineer and friend of mine to look at this”.

When Rob saw the basement he was uncertain about the precise cause of the problem, but not about what needed to be done: “You need to immediately install bracing to prevent an imminent collapse of the house and you better start planning for the replacement of the entire foundation … soon. Because whatever the cause, this concrete is toast”.  Getting quick, knowledgeable advice from solid engineers was both depressing and extremely helpful.  At least we didn’t waste time and money with useless attempts at a fix.

As reality sunk in, and I got a sense of just how disruptive and expensive the replacement project was going to be, I called my insurance agent to make a claim.  I sent him photographs of the crumbling concrete, a copy of the Rob’s report, and told him he could visit any time.  He said he would forward the information to the insurance company and they would contact me.

The insurance company assigned an adjuster and retained a consulting engineer to review the information and visit the property.  A couple of weeks later I received the first of what would be three rejection letters.  The letter stated that the failure of the concrete foundation was due to the pressure of groundwater and/or the action of frost against the foundation.  The letter explained that my policy contained an exclusion for damage caused by water, and as much as they would sincerely like to help, they had to deny any liability for my loss.

Picture this – there were eighth to half-inch wide cracks that went clear through the foundation walls to the soil on the other side.  Lots of them. Yet not a drop of water had ever come through those cracks.  The insurer’s engineer had seen these cracks.  How could groundwater with sufficient pressure to crack 12 inch thick hardened concrete walls not also cause water to come gushing through those cracks?  Seemed like a good question to me. Although not one that interested the insurance company.

Since I’m a curious kind of guy I wanted to know the answer (this was before we had the results of the petrographic analysis).  The only way to find out was to do a little groundwater study, so I had monitoring wells installed around the house.  This turned out to be the first of several pricey out-of-pocket research projects to satisfy my curiosity. Mrs. Okun was not wholly enthusiastic about the cost of these projects.

Once the monitoring wells had been installed and water levels were measured, it became apparent that the water table was too deep for groundwater to be pressuring the foundation; the insurer’s engineer readily agreed.  At that point I was still naïve enough to believe that the insurance company would welcome this new information and my claim check would be forthcoming. Hah!!!

Second Claim, and Rejection

So while the insurance company was developing their first rejection letter, we asked our engineer to move ahead with collecting concrete core samples and conducting the petrographic analysis needed to identify the cause of the failure. This was another pricey item, but my curiosity was demanding an answer.  It took a little while to get the results, but they were definitive: the presence of the mineral pyrrhotite in the concrete’s coarse aggregate had caused the concrete to fail.  Part 1 of this mini-series discusses the hazard pyrrhotite poses to concrete in more detail.

I forwarded the petrographic results and the groundwater level measurements to the insurance company and asked them to reconsider my claim.  Their first engineer was not well versed in concrete chemistry, so the insurer retained a concrete specialist to review the petrographic report.  This second engineer concluded that the problem with our foundation was due to sulfate in the groundwater around the house.  In case you are curious, the new engineer did no testing of the groundwater to confirm this hypothesis. It’s a small world of engineers who know concrete chemistry and I had considered hiring this same engineer to do my petrographic analysis; I’m glad I didn’t.

Well, the insurer once again rejected our claim for a bunch of legalistic reasons and because in their opinion the collapse – which to them was not legally a real collapse – was caused by sulfate in the groundwater around our house.

Third and Final Claim Rejection

Fortunately, sampling the monitoring wells that were already installed to test for sulfate was easy and cheap.    So I wasted no time getting this done.  No surprises here, groundwater sulfate concentrations around my house were exactly the same as the published background levels for sulfate in north central Connecticut where the house is located. 

As you would expect, I sent the information on groundwater sulfate concentrations to my insurer with a bunch of legal arguments and asked them to again reconsider our claim.  I broke the claim into seven parts to make it easier for the adjuster to understand, not that this mattered.

Over time the pyrrhotite induced deterioration of the concrete caused the basement walls to expand, which pushed the outer walls of the house upward.  This irregular upward movement causes windows and doors to get stuck in their casings so they will not easily open or close.  This damage symptom was one of the parts of the claim I made.  Here’s the insurer’s response to that part of the claim, verbatim:

The Insurance Company’s Engineer Mr. Smith, PE, has determined that only a portion of the damage to the upper floors resulted from the movement of the foundation.  There has not been any structural impairment of the upper floors and therefore, these portion of the upper floors have not collapsed as that term is defined in Beach v. Middlesex Mutual Assurance Company.  Therefore, for the reasons stated above, any portions of the upper floors which have sustained a loss, which loss was not caused by any movement of the foundation is not covered by the additional coverage for “collapse”.  Furthermore, the collapse coverage specifically provides that “collapse does not include settling, cracking, shrinking, bulging or expansion.”  Also, there is no coverage for this loss because exclusion 2.h.(6) quoted above excludes a loss “caused by: … settling, shrinking, bulging or expansion, including resultant cracking of pavements, patios, foundations, walls, floors, roofs or ceilings.”  However, those portions of the upper floors which may have sustained damage because of the collapse to the foundation may be covered as “direct physical loss to covered property involving a collapse of a building or part of a building (the foundation) caused only by one or more of the following…defective materials…”  Therefore, the Insurance Company will cover the repairs to the openings, windows, doors or walls of the upper which are related to the movement of the foundation.

After I read that last sentence, I reread it about ten times.  I thought, “Well I’ll be!” They have finally agreed to cover something, because to fix the damage to the upper floors, it would first be necessary to fix the foundation! Yes!  All this effort is finally going to pay off! 

When I called the insurance adjuster in the morning to coordinate the next step, he explained that I had misunderstood their letter.  That last sentence in the paragraph where it sounded like they were going to cover some of the damage, I got that wrong.  That language was their way of letting me know they weren’t going to cover anything, because as I had surmised, the only way to fix the upper floors was to fix the foundation, and they weren’t going to cover that at all.


Last three thoughts for this post:

  1. In addition to the claim for damage to the upper floors, part of my final claim was for the reimbursement of engineering and testing costs, here’s their response to that: “The policy terms relating to loss payment do not provide coverage for engineering and testing fees to determine the basis for the loss and there are no engineering or testing fees required to determine the nature and extent of the repairs to any upper portions of the structure for which there may be coverage”. That was galling after all the fake technical arguments they had thrown at me.
  2. Ultimately with the help of a good attorney we entered mediation with the insurer and received a settlement for some of our costs, for which we remain grateful.
  3. Having a solid technical background was immensely helpful as was having access to the talented engineers at OTO and in the broader out-of-OTO network.

Stay tuned for Part 3, what it’s like to have your home’s foundation replaced.

In 1989 my family and I moved from a pleasant Boston suburb to rural Ellington in north central Connecticut. We loved Ellington and quickly made good friends, primarily the parents from our daughter’s play group. Our house was set on 5 acres of mostly forested land, I installed a playground set with swings for the kids and we had many enjoyable times. Life was good, or so it seemed.

However, unbeknownst to us, something insidious was happening to our house that was beyond our wildest imaginings; the concrete support structure (i.e. the foundation) was quietly crumbling away beneath our feet. Who even knew that this was possible? I’m an environmental chemist with a lot of experience and the idea that concrete could literally corrode away over the course of a few years was news to me.

It’s Even Worse than You Thought

In 2005 during a routine trip to the basement I stopped to look at the concrete walls and it became apparent that something was very wrong. Big vertical, horizontal and diagonal cracks had opened up in the concrete walls and the formerly solid concrete had become shockingly friable – you could easily extract a piece of concrete with your hand and rub it to dust between your hands. There was also a snowy-white efflorescence covering most of the walls.

The next day at work I told OTO’s senior engineer Mike Talbot about what I had observed and asked him to take a look. When he did he was dumbfounded and recommended that I have a structural engineer friend of his, Rob Johnson, come by to give his opinion.

A few days later Rob was in the basement saying that he was uncertain what the precise cause of the problem was, but I needed to immediately hire a contractor to install temporary shoring to forestall the imminent collapse of the house. This was bad enough, but the next piece of news from Rob was even worse: I needed to start making plans for the total replacement of the basement walls and foundation footings because the concrete was clearly disintegrating rapidly.

Rob sketched up some plans for me to give to the contractor and soon we had these large wooden supports holding up the basement walls. Speculating, Rob suggested the underlying problem with the concrete could be ASR (alkali-silica reaction), but to find out for sure would require collecting concrete core samples and the petrographic analysis of the cores. Petrographic analysis involves making thin slices from the cores, staining them, and reviewing them under a special microscope.

Concrete coring, showing wall damage

Pyrrhotite Revealed

While we were not this first ones in the area to have a problem with crumbling concrete, to my knowledge, we were the very first to collect core samples for petrographic analysis.

When we got the lab results back it turned out, there was no ASR in the core samples, instead the problem was the presence of pyrrhotite in the concrete’s coarse aggregate.

To put this all in an understandable context, it’s helpful to know a little bit about concrete. Concrete is made from four basic ingredients: cement, sand, coarse aggregate (eg small stones), and water. Concrete is a very strong and durable building material (think Roman Colosseum), but there are two types of stress that concrete cannot tolerate: corrosive acids and tension forces. It turns out that pyrrhotite provides both of these stressors in abundance.

Pyrrhotite is basically a chemically unstable form of iron pyrite, made up of iron and sulfur. When pyrrhotite is mined out of the ground and is exposed to air and moisture, it begins a long slow degradation reaction. As the pyrrhotite degradation progresses, the sulfur turns into sulfuric acid and the iron becomes the mineral hematite. Any exposure to acid is bad news for concrete, but sulfuric acid is by far the worst. It immediately begins to dissolve the cement paste that binds the other concrete ingredients together.

The problem with hematite, which is effectively a type of ferric oxide or rust, is that it takes up more space in the concrete matrix than was occupied by the pyrrhotite it replaced. This results in internal pressure and expansionary forces. These expansionary forces are more than the acid-weakened concrete can withstand and massive cracking begins to appear. At first the cracks are narrow, but they soon expand to an inch or more across. What I saw on my trip to the basement that day was the characteristic cracking pattern referred to as “map cracking”, so named because the irregular cracking resemble roads on a map.

As the cracks widen, the basement walls effectively grow taller, which pushes the sides of the house upwards. Windows no long open and close and doors become crooked, no longer able to shut. The sides of the house became higher than the middle of the rooms. Welcome to Alice in Wonderland.

As has now been shown by so many homes and other buildings in north central Connecticut and south central Massachusetts, the pyrrhotite containing aggregate originating from Becker’s quarry in Willington, CT has laid to waste real estate values.

What’s next?

This story is getting long, but it wouldn’t be complete without the parts about the so-called insurance company (names changed to protect the unbelievably unhelpful), and the parts about the actual reconstruction of the foundation and basement walls. So stay tuned for parts 2 and 3 – and BTW, yes this all really happened to us and it is still happening to many folks in north central Connecticut and south central Massachusetts.

Over the past year there have been a number of articles published about reproductive risks to orcas (killer whales) posed by PCBs (example articles 1, 2, and 3).  Some of these articles go so far as to claim that orcas are threatened with extinction due to their reproduction being inhibited by PCBs.

But do PCBs really pose really pose an extinction risk to orcas?  Or have these authors used limited information to draw conclusions that are out of proportion with the actual science?  With this post I want to consider what we know about orcas and PCBs and evaluate whether the warnings in these recent articles are realistic.

orcas photo


Orca Characteristics and Behavior

Orcas are among the top predators in the ocean.  They are not true whales, instead they are the largest member of the dolphin family.  Although all orcas belong to the same species, scientists that study them group them into three subpopulations (resident, transient and offshore) based on their behavior.  As you would guess, resident orcas live in near-shore locations and remain there for their entire lives, they eat either fish or other marine mammals.

The transient orcas remain close to shore, but migrate along the coast in the pursuit of prey, which consists of mostly of other marine mammals.  Offshore orcas are the least well known, but they live and feed far from shore and are believed to feed on sharks and other large fish or marine mammals.  Although all three groups belong to the same species, they do not interbreed or otherwise mix socially despite being considered highly social within their own group.  As a species, orcas are generally not considered endangered.

Almost everything we know about orcas comes from studies of resident populations because they are relatively easy to monitor.  Possibly the most carefully studied orca group (known as the Southern Resident Killer Whales), lives in the waters of the Pacific Northwest, off the coast of Washington state and southern British Columbia.  Two other closely monitored resident orca groups are: a pod residing off the west coast of Scotland (known as the West Coast Community); and the Northern Resident group, which lives off the more northerly coast of British Columbia.

Orca Population Decline

While the (North American) Southern Resident and (Scottish) West Coast Community groups are different in many ways, both are now experiencing population decline.  In the case of the Southern Resident group, which now has 75 individuals, scientists concluded the decline is due to the reduction in their nearly exclusive food source, Chinook salmon.  Scientists have found a close link between orcas’ annual reproductive success and the abundance of Chinook salmon in their home waters.  A recent decline in the salmon population is believed to have resulted in the orcas expending more effort to achieve an adequate diet and having less reproductive success.  These scientists are hopeful that the key to increasing the Southern Resident group’s population is changing the salmon fishery management to ensure the orcas receive adequate nutrition.

In contrast, the West Coast Community orca group off of Scotland may indeed be on the path to extinction.  This group consists of four-females and four-males, a total of 8 individuals, with no new births in the group in 25 years.  In fact, the group was recently reduced when an older female died after becoming entangled in fishing lines.  Scientists speculate that the remaining females may now be too old to give birth.  There is no agreed upon cause for the reproductive failure of the West Coast Community orcas, however, speculation has whirled around the idea that PCBs may have caused a lack of fertility among the females as a result of its ability to mimic estrogen.

PCBs and Orcas

One report that sheds considerable light on the question of PCBs and orca reproduction is a 2000 Institute of Ocean Studies article, which describes a study in which scientists collected fat samples from 47 live, wild orcas off the coast of British Columbia and tested these samples for PCBs, furans and dioxins.  The samples were collected from transient orcas as well as individuals form the Southern and Northern Resident Groups (note that the Northern Resident Group is distinct from the Southern Resident orcas, but there is some overlap of their territories of the coast of British Columbia).  This study is among the most comprehensive investigations of PCBs in orcas.

The study had three important findings relative to orca reproduction:

  1. The study found all of the orcas sampled had surprisingly high concentrations of PCBs in their fatty tissue. The transient and Northern Resident orcas had higher PCB concentrations than the Southern Residents.  This is believed to be attributable to their different diets.  Transient and Northern Residents consume primarily marine mammals and Southern Residents consume primarily salmon.  Salmon has significantly lower PCB concentrations than do the marine mammals preyed on by the orcas.
  2. In each of the three populations the adult males had significantly higher PCB concentrations (and presumably higher PCB body burdens) than did the adult females. Since their diet and thus their potential PCB exposures are the same, the only explanation for this is that the adult females transfer their PCB body burden to their young during gestation and after birth through their milk when nursing.  Because the fat content of orca milk is high, and because this fat carries the PCBs accumulated by the mother, these PCBs are transferred to the nursing young.  It is estimated that 60% of the mother orca’s PCB body burden is transferred to their young by nursing.  The transfer of PCBs from mothers to their young is seen in other mammals as well.
  3. The concentrations of dioxins, furans and dioxin-like PCBs in the orca fat samples were less than anticipated based on the relatively high concentration of non-dioxin like PCBs. The authors suggest that this finding may explain how the orcas could tolerate such high PCB body burdens, without experiencing adverse effects such as reproductive failure.  The authors speculate that the more toxic dioxins, furans and PCBs may have been metabolized by other animals lower on the food chain such that only the less toxic and more chemically stable PCBs are actually passed on to the orcas in their food.


The objective of this post was to consider whether the available scientific evidence supports the claim that PCBs may drive orcas to extinction as a result of reproductive failure.  It is undeniably true that orcas carry high PCB body burdens, and that these PCBs are the result of their diet, whether that diet consists of fish or marine mammals.  However, based on the 2000 Institute of Ocean Studies report, it does not appear that high PCB body burdens are contributing to reproductive failure in the populations studied.

As odd as it may seem, some of the strongest evidence for orca reproductive success from this study is the much lower PCB concentrations found in the adult females compared to those detected in the adult males.  Since the PCB exposure of the females and males are similar (they all derive PCBs from their diet), the consistent large differences in concentration in their fat tissue can only be explained by the transfer of the adult female’s PCBs to their young.   Sexually immature females and males have similar PCB concentrations.  But, upon reaching reproductive age, the female’s PCB concentrations drop, while the male’s PCB concentration continues to increase with age.

The study data indicates that the orcas continue to reproduce successfully among the transient and the resident orca populations on the North American west coast despite their high PCB body burdens.  In other words, the PCBs do not appear to be adversely impacting the orca’s reproduction.

It may not be appropriate to extrapolate the results of the North American orca/PCB study to the decline of Scotland’s West Coast Community group.  However, the study clearly does not provide support for the contention that PCBs are causing a worldwide decline in orca population.

PCB or Non-PCB

The other day I got an email asking a good, basic question about the federal PCB regulations: “Where did the 50 ppm regulatory cut-off for PCBs come from?”  Is it a science based number? Or did the 50 ppm number just get pulled out of the air?

The more I thought about it, the more consequential the question seemed.  Thus a new PCB blog post seemed to be in order.  As you’ll read, the 50 ppm level wasn’t exactly science based, but then it wasn’t totally pulled out of the air either.

What does TSCA say?

Congress passed and the president signed the Toxic Substances Control Act (TSCA) in 1976.  This statute directed EPA to develop two sets of PCB regulations that became known as: (1) the 1978 PCB Disposal and Marking Rule; and (2) the 1979 PCB Ban Rule.  TSCA does not specify a PCB concentration cut-off limit to let EPA (or the rest of us) know exactly what Congress had in mind as to how concentrated PCBs had to be for them to fall into the regulatory net.

Wise legislators must have agreed that setting a regulatory cut-off limit is a decision best left to the professional staff at the regulatory agency. (I will leave the question of whether the phrase “wise legislators” is an oxymoron for a more politically oriented blog).  So TSCA is silent on the issue of PCB cut-off concentrations.  This was something EPA needed to figure out.

What does EPA say about the 50 ppm cutoff?

In the draft public comment version of what became the Disposal and Marking Rule, EPA proposed a 500 ppm cut-off limit for the regulation of PCBs.  But, by the time the final rule was published in the Federal Register (February, 1978), EPA was already getting cold-feet about this high a limit.  The agency warned in the preamble to the Rule that they would likely soon reduce the cut-off level to something in the neighborhood of 50 ppm, but needed to go through a more prolonged regulation development process before they did so.  Quoting from the preamble:

“The Agency is aware that adverse health and environmental effects can result from exposure to PCB’s (sic) at levels lower than 500 ppm; however, at this time the Agency is not establishing a level based on health effects or environmental contamination but rather a level at which regulated disposal of most PCB’s can be implemented as soon as possible”.

EPA goes on to explain that they had only recently acquired the additional scientific information needed to support a lower cut-off level, and that this information was not available in time to include in the administrative record or hearings for the Disposal and Marking Rule.  More from the Rule’s preamble:

“As a consequence, the 500 ppm definition for a PCB mixture, as proposed, is included in this final rule making.  However, the Agency plans to propose a lower concentration of PCB’s, possibly in the range of 50 ppm or below, to define PCB mixture in the forthcoming . . . regulations”.

In accordance with EPA’s warning, the preamble to the May, 1979 PCB Ban Rule explains that EPA had in fact decided to adopt the 50 ppm cut-off level.  This was after the Agency considered cut-off levels of 1 ppm, 10 ppm, 50 ppm and 500 ppm.  EPA concluded that reducing the cut-off level to 10 ppm was impractical because it would bring far too much physical material and too many unrelated chemical processes into the PCB regulatory net.  EPA pointed out that a 1 ppm cut-off level would obviously be even more impractical than the 10 ppm level.

So the 50 ppm level was chosen as the happy medium.  It was a concentration that could be “administered” by EPA (presumably unlike the lower 10 ppm and 1 ppm levels) and yet would capture hundreds of thousands of pounds of PCBs that would have gone unregulated with a 500 ppm cut-off level.

So, that is the story of where the 50 ppm PCB cut-off concentration came from.  It wasn’t rocket science, one could argue it was barely science at all.  In retrospect it was a compromise between those interested in controlling as much PCB as possible and those whose focus was on what could realistically be accomplished.

Now some might wonder why it is that under the 1998 PCB Mega Rule there is a 1 ppm cut-off concentration for PCB remediation waste, but that’s a question for another blog post.

caulk and bricj

PCBs, polychlorinated biphenyls, are a group of related chemicals that were used for a variety of applications up until the 1970s.  In the 1960s the development of improved gas chromatography methods allowed environmental scientists to become aware of the environmental persistence and global distribution of PCBs in the environment.  Since that time there have been hundreds of studies conducted to better understand the environmental transport and fate of PCBs.

However, it has been only over the past 20 years or so that studies have focused on learning more about PCBs that were incorporated into building products and their fate in the indoor environment.  Much of what has been learned is surprising and counter-intuitive.

For example, while it is generally true that PCBs have low volatility and low water solubility, it turns out that even at room temperature they are volatile enough to permit them to migrate in and around buildings at concentrations high enough to have regulatory implications.  This migration may take place slowly, over the course of several decades, but in some instances, it has happened in as little as a year.  With today’s sensitive instrumentation, chemists are able to track the movements of even tiny concentrations of PCBs as they migrate.

This post is a primer on the three primary categories of building materials which contain PCBs and how their PCBs can move inside of buildings.

Primary Sources

As the name suggests, primary sources are building materials that were either deliberately or accidentally manufactured with PCBs as an ingredient prior to their installation in a building.  The most common primary sources are:

  • Caulking;
  • Paint;
  • Mastics;
  • Various surface coatings; and
  • Fluorescent light ballasts (FLBs).

FLBs are different from the other materials on this list because they use PCBs in an “enclosed” manner.  This is defined as use in a manner that will ensure no exposure of human beings or the environment to PCBs.   However, with continuous use FLBs are known to deteriorate, sometimes resulting in the release of PCBs.  Only FLBs manufactured before the PCB ban (1979) should contain PCBs and by now (2017) any of these older PCB containing FLBs should have been replaced with non-PCB ballasts since even the youngest PCB FLBs are almost 40-years old.  FLBs are considered to have had a functional life span of only 10-15 years.  The type of PCBs used in US-made FLBs were almost exclusively Aroclors 1242 and 1016.

The other primary PCB sources on the above list are considered to be “open” PCB uses because, unlike FLBs, the PCBs were not contained in an enclosure.  In most of these cases PCBs were added to the materials to improve the performance of the products by contributing: fire resistance, plasticity, adhesiveness, extended useful life and other desirable properties.  For PCBs to impart these properties they were generally included at concentrations ranging from 2% to about 25%; this is equivalent to 20,000 parts per million (ppm) to 250,000 ppm.  The most common PCBs found in US-made building materials are Aroclor 1254 followed by Aroclor 1248, 1260 and 1262.

PCBs can sometimes be present in primary sources by accident rather than by design.  The presence of Aroclor PCBs in primary sources at concentrations less than 1,000 ppm (equal to 0.1%), or non-Aroclor PCBs at any concentration, may indicate an accidental PCB use.

Under the federal PCB regulations primary sources of are referred to as PCB Bulk Products and they are regulated when their PCB concentration is 50 ppm or greater.

Secondary Sinks and Secondary Sources

When a PCB primary source is in direct contact with a porous building material, the PCBs in the primary source can often migrate from the primary source into the porous material.   Porous building materials known to adsorb PCBs in this way include concrete, brick and wood.  When this migration occurs, the now PCB containing porous materials are referred to as secondary PCB sinks.  Secondary sinks often have PCB concentrations in the range of 10-1,000 ppm.

While the federal regulations apply to primary sources when their concentration is 50 ppm or greater, requirements for secondary sinks are stricter.  They are categorized as PCB Remediation Wastes and are regulated when their PCB concentration is 1 ppm or greater.

In some situations, the PCBs in secondary sinks can be remobilized and either migrate directly into other porous materials or they can volatilize into the air.  When this occurs, these secondary sinks may be referred to as secondary sources.  In practice one hears the terms secondary sinks and secondary sources being used interchangeably.

Tertiary Sinks and Sources

Tertiary sinks arise when PCBs from primary or secondary sources volatilize into the air and then condense onto other materials in a building.  The significance of volatilization as a PCB migration pathway was underappreciated until recent times because the relatively low volatility of PCBs suggested that the volatilization rate was too low to be meaningful.  However, laboratory testing and numerous real-world examples have demonstrated that volatilization of PCBs from primary and secondary sources with redeposition on other materials can be significant in some settings.   Tertiary sinks often have PCB concentrations between 1-100 ppm.

Some authors prefer to use the term secondary sinks to describe both secondary and tertiary sinks.  Personally, I prefer to use ‘tertiary sinks’ to identify materials affected by indirect contact (through the air) and ‘secondary sinks’ to identify materials affected by direct contact to primary sources.  However, I acknowledge that it is not always evident whether a material is a secondary or tertiary sink.

Why Understanding PCB Sources and Sinks Matters

Understanding the ways that PCBs move around in buildings is important if your goal is to reduce potential exposures inside of buildings.  It is a frequent occurrence in PCB building remediation for primary sources to be removed only to find that indoor air concentrations have not been reduced to the extent expected.  Or for air concentrations to fall immediately after remediation, only to return to previous levels with the passage of time.  This is often due to an insufficient appreciation for the influence and action of secondary and tertiary sinks.

If you have a particular PCB in building condition that needs a fresh set of eyes to review it, consider reaching out us for another opinion.

Soxhlet Extraction Schematic
Soxhlet Extraction Schematic

Thanks to a friend’s sharp eye, I recently learned something new about the analysis PCB caulk samples.  Because of its potential significance I thought it deserved a special blog note.

First a little background on how caulk samples get tested for PCBs.  It’s basically a three step process:

  1. First a carefully measured amount of the caulk sample is extracted with an organic solvent. As a chemist would say, PCBs would rather be dissolved in a non-polar organic solvent than to be in the caulk, so they move from the caulk to the solvent.  If you are in USEPA Region 1 this extraction must be conducted using “the Soxhlet method” also known as EPA Method 3540C.  The Soxhlet method is the gold standard of extraction methods, but it uses a lot of energy, water, solvent and glassware so ecologically it is not a very “green” method.  Additionally, it takes a long time.  The method calls for the extraction to proceed for 16 to 24 hours. In other EPA Regions other extraction methods (such as sonication) may still be acceptable.
  2. Once the PCBs have been extracted from the caulk to the solvent phase, the solvent needs to be cleared of the other potentially interfering chemical schmutz that got extracted out of the caulk along with the PCBs. These cleanup steps are fairly critical before you run any of the extract through the gas chromatograph (GC).  The GC is the instrument that will tell the analyst how much PCB is in the extract.
  3. Following the cleanup steps you inject a very small portion of solvent extract  into the GC. At the end of the GC is a very, very sensitive detector that can measure the truly minuscule amounts of PCBs in that may have been in the sample.  The detector generates a signal that allows the analyst to back-out the concentration of PCBs that were originally in the caulk, if any.

Well this probably seems simple enough, but think for a minute about what might happen when your GC is set to measure PCB concentration levels of between 1 and 10 ppm and all of a sudden a caulk sample comes through with 200,000 ppm of Aroclor 1260! Yikes!  This is the equivalent of trying to weigh a full grown African elephant on an office postage scale!  You are not going to get an accurate weight, and your postage scale will never be the same.

And of course it’s not a happy day for the analyst who will now need to spend many hours or days getting the residual PCBs out of that very sensitive GC detector, not to mention all the grossly contaminated glassware and other lab equipment.  Obviously labs need to take steps to protect themselves from this possibility or they would very quickly be out of business.

How Labs try to Reduce this Risk

One thing labs can do to reduce the risk of blowing out their GCs is to ask the people submitting samples if they know the approximate concentration of PCBs in the caulk.  But usually they don’t know, and if it were your lab would you necessarily take the word of the person submitting the sample?  I’m not sure I would.

Another option is to pre-screen samples using a “quick and dirty” method to get a rough idea of the PCB concentration.  Such a method might involve a very simple extraction, followed by a big dilution of the extract to reduce the PCB concentration (if any are actually there) followed by injection into the GC.  Something very close to this procedure is known to EPA as Method 3580A, but is also known colloquially as the “swish and shoot” method.

Now this method is completely fine for getting a quick read on the relative PCB concentration in a sample.  In fact, if the results from the swish and shoot screening shows the analyst that the sample is hot (i.e. lots of PCBs well in excess of the regulatory limits) then there really is no need to conduct any further analysis because the person submitting the sample is in most cases just wanting to know whether the concentration is greater or less than the regulatory thresholds for PCBs.  So some labs stop the analysis at this point and report the results from the sample prepared with the method 3580A extraction.

Situations Where Swish and Shoot Results might Steer you Wrong

If a sample is analyzed following a relatively inefficient extraction and the resulting sample concentration still exceeds regulatory standards, then a more efficient extraction can only result in a concentration that exceeds standards by an even greater amount.  As long as the sole analytical objective is to identify whether or not samples exceed regulatory standards, then this objective can be satisfied by a less efficient extraction provided the result is greater than the regulatory standard.

However, if your analytical objective is also to map PCB concentrations over an site area to achieve a clearer picture of how concentrations change spatially in the field, then you need an extraction and analysis protocol that is consistent, efficient and reproducible.   Without these qualities you won’t be able to reliably tease out the forensic trends you want from the data.

The lesson to be learned  from choosing  the right extraction method for PCB analysis is the timeless quality assurance principle of identifying how you want to use data before you collect samples and analyze them.  Some of the biggest problems with scientific studies can arise when data is collected for one purpose, but then used in a way that was not anticipated by the scientists who collected and analyzed the samples.  Data that satisfied the original study’s objectives may not be suitable for a subsequent study with different objectives.

So-called “meta studies” and a number of retrospective studies where batches of pre-existing data are aggregated to increase the statistical power of a study’s conclusions can be guilty of not thinking about whether the data quality objectives of the original studies meet the needs of the new study.  What motivates the meta study authors is creating as large a data set as possible to give their results statistical significance.  But this quest for large data sets can cause the consideration of data quality objectives to fall by the wayside.

These “big data” studies can sometimes make for splashy headlines because the large number of samples make results look statistically significant.  But too often these results need to be walked-back because the authors did not adequately consider the data quality objectives of the original studies in assembling their meta-data sets.

Last Word

So to reiterate again, think about how your PCB data will be used before you submit the samples to a lab, then make sure the extraction and analysis methods to be used will give you the data you need.

education1Three years ago I wrote a draft post about the cost of PCB removal in schools, but then never finished it.  What reminded me about it was a recent article[1] by Robert Herrick et al in which he developed an estimate of the number of schools in the US that may contain PCBs in caulk.  His estimate is presented as a range: 12,960 to 25,920 schools.

Herrick speculates that this range is likely to be low, and I agree.  My own estimate from 3 years ago was closer to 43,000.  Given the statistical limitations of our methods, trying to extrapolate from small possibly non-representative sample sets to the entire population of US schools, our numbers are actually pretty close.

However, what particularly interests me is the next step in the analysis, estimating the potential costs of remediating all those schools.  This is a step that Herrick, perhaps quite wisely, did not take.  With that introduction, what comes next is a lightly edited version of my 2013 unpublished post in which I do try to estimate possible costs of removing PCBs from schools nationwide.

Did EPA consider compliance costs for municipalities in its development of the PCB regulations?

When the USEPA proposes new regulations, two of the questions Congress and the public usually ask are: “How much will it cost to implement these new requirements? And is it worth it?”  To answer these questions, EPA will typically conduct a “cost-benefit analysis.”  This analysis is supposed to demonstrate the advantages of EPA’s proposed actions and explain how the benefits are worth the cost.

These analyses aren’t always 100% accurate because it can be hard to know all the exact costs associated with changes just as it can be difficult to anticipate all the benefits.  None-the-less, the cost-benefit analysis is a good-faith effort to consider the positives and the negatives associated with a proposed regulation.  Developing these analyses is one reason EPA employs economists.

Surprisingly though, EPA’s 1998 PCB Mega Rule contained no cost-benefit analysis; there was not a single sentence that spoke to the issue of the costs of these regulations even though they have imposed huge financial burdens on the public and private sectors.  To give EPA some benefit of the doubt, much of that burden is only now becoming evident as the full extent of PCBs in schools and other buildings is being discovered.

Isn’t it worth any cost to protect schools and children from any risk?

There is no answer to this question that will satisfy everyone, but as a society we can take steps to limit the negative impacts or real demonstrable risks in our schools.  By real risks I mean threats that have been shown to actually harm schools and children under real world conditions.  Examples from the top of my list of demonstrated risks would include cars and guns, but PCBs in building materials wouldn’t be on my list at all.  Why aren’t PCBs on my list of threats? The answer is simple, there are no credible scientific studies showing harm to the health of schools, students or staff despite the presence of PCBs in buildings for over 60 years.

But in this post I want to focus on the financial burden the PCB regulations are putting on schools and public education.  As a former board of education member in a small New England town, I can tell you first-hand about the battles to secure funding for public school systems.  Every year costs go up and every year vocal groups want to pay less tax and accuse administrators of mismanaging funds.

Anyone who thinks that a typical municipality can come up with extra millions of dollars to pay for PCB removal in a school ought to spend some time on their local board of education.  There isn’t extra money to do PCB remediation in a town’s budget; that money is going to come right out of the education budget.  The harm done to a typical school system by redirecting funds from educational programs to PCB removal is much greater than any harm done by the PCBs.

So, did anyone at EPA think about PCB remediation costs? No? Let me help.

So back to the threshold question, did EPA think about the financial burden it was placing on municipalities when it retroactively banned PCBs in building materials including those already in schools?  If they did, I can’t find any evidence of it.  To be helpful, I am providing below a very rough estimate of the possible national cost of removing PCBs from US K-12 schools.

The approach I use is a method I picked up in college called “the back of the envelope” approach.  I’ll leave developing a more rigorously researched approach to the economists at EPA; it’s been my experience that the back of the envelope approach often gets you remarkably close to the right answer.

The Back of the Envelope Accounting Office

From a quick Google search I discovered that there are approximately 132,000 private and public K-12 schools in the US.  As a somewhat educated guess, let’s assume that 33% (one in three) of these schools have PCBs in at least one building.  Further, let’s assume that the average cost of testing and removing PCBs from an average school is $2 million.  Some schools will cost less to remediate, but many will cost much more.  Some quick multiplication takes us to a cost of $87 billion to remove PCBs from all public and private K-12 schools.  I recently heard Speaker of the House Paul Ryan say that $80 billion is a lot of money even in Washington.

There is obviously a lot of uncertainty in this estimate.  My guess is that I underestimated the actual number of affected school buildings and that I also underestimated the average cost per building to remove PCBs.  None-the-less it is a starting point and I am going to use it below for a few simple comparisons.

What do we spend per year on Public K-12 Education?

How much is an $87 billion PCB removal cost in terms of the nation’s K-12 education budget?  According to the National Center for Education Statistics, public school districts had a total budget of $610 billion for the 2008-2009 school year.  This amount historically increases by only 1-2% per year so I am just going to use the 2008-2009 budget numbers because the uncertainty in the other values I am using in this analysis likely swamp out the small change I would make to adjust the school budget number.  Of the total K-12 spending budget, $519 billion went to current education, $65.9 billion went to capital construction projects, $16.7 billion went to cover interest payments and $8.5 billion went to other costs.

Cost of Getting PCBs out of Public Schools

The $87 billion for PCB removal is for public and private schools, and about 75% of all K-12 schools are public.  So assuming the costs for PCB removal are the same for either public or private schools, the cost for removing PCBs from just public schools will be about $67 billion.  This means the PCB removal cost would be about 11% of one year’s total national education budget or about 13% of the annual operating budget.  However it would be about 100% of the capital construction projects for a year.

This analysis is obviously too simplistic, because some school systems will not have any PCBs, and some will likely have a lot.  There is no apparent way for school systems across the country to even out these costs nationally among themselves, although there may be some ability for states to even out the costs within a state.

Still it highlights what a large issue PCBs in schools can be for a municipality and it clearly answers why most school administrators want to stay as far away from testing their schools for PCBs as they possibly can.

Final Thoughts

Two final thoughts for this post:

First and foremost – If there were credible scientific evidence that PCBs in schools were actually causing harm to the health of students or staff I would be fully supportive of decisions to get them out regardless of the cost.  But this evidence does not exist and not for lack of trying on the part of research scientists.  The fact is that most students and staff receive significantly more PCBs daily in their diet than they do from being in school buildings. The 60+ years of history of PCBs in building materials has simply not turned up evidence of harm to the health of building users.

Second – The estimated $2 million per school PCB removal cost is potentially well short the actual average cost per school because in many cases schools simply cannot be made PCB free.  Instead school buildings have been closed down with the children and staff reassigned to other schools.

In affluent communities the solution to this problem might be demolishing the old building and constructing a new one, but in more typical American communities it means a long-term loss of educational resources and a significant lessening of educational capacity as the old school building is shuttered and becomes a long-term reminder of what has been lost.


[1] “Review of PCBs in US schools: a brief history, an estimate of the number of impacted schools, and an approach for evaluating indoor air samples”; Herrick, R.F., Stewart, J.H., and Allen, J.G.; Environ Sci Pollut Res (2016) 23: 1975-1985.


A lot of BS passes itself off as good science these days.  While for the most part we applaud the good science that leads to improved environmental protection and better public health, we don’t hesitate to call out the BS when we see it. In that vein, I recently had the good fortune to receive this link to a John Oliver segment  on that very topic. I strongly encourage you to invest the time to watch it, it is very funny and very true!  Enjoy.

In Part 1 of this post, I wrote about the misguided push in my home state of Connecticut to test more schools for PCBs. There’s a misconception that PCBs, even with the low potential doses likely to occur in the indoor environment, pose a health risk. This misconception persists despite a 50+ year history of PCBs in many school buildings without a documented instance of a student, teacher or other staff member experiencing adverse health effects indicative of PCB toxicity. And yes, scientists have looked.

While the presence of PCBs in buildings does not seem to have caused bodily harm, the act of removing them from school buildings can be devastating to school and municipal budgets. Experience shows that removing PCBs from schools is a very expensive process; one whose budget can grow exponentially as more information and test data becomes available. There are relatively few communities whose annual school budgets can withstand the impact of a school PCB removal project.

I ended Part 1 with this paragraph:

“TSCA – the Law of Unintended Consequences
You can read the Toxic Substances Control Act (TSCA) from cover to cover and you’ll find nothing about removing PCBs from schools or other buildings. Take a look at the 800+ page legislative history of TSCA and you will still find nothing about PCBs in schools. How about EPA’s PCB regulations (40 CFR 761)? No, still nothing about removing PCBs from schools or other buildings. So if there is nothing in the statute or the regulations about removing PCBs from schools or other buildings, and if there is no evidence that PCBs in building materials pose a health risk, then what explains the need to assess and remove PCBs from schools?”

The goal of Part 2 is to answer that question.


In the beginning . . .
From their first publication in 1978/79 until the 1998 Mega-Rule changes, the PCB regulations contained what I call the “in-service rule”, which reads in part:

“NOTE: This subpart does not require removal of PCBs and PCB Items from service and disposal earlier than would normally be the case. However, when PCBs and PCB Items are removed from service and disposed of, disposal must be undertaken in accordance with these regulations. PCBs (including soils and debris) and PCB Items which have been placed in a disposal site are considered to be ‘‘in service’’ for purposes of the applicability of this subpart”.

My naive interpretation of the in-service rule is that PCBs that were already incorporated into some product – and thus in-service – could remain in service until that product was taken out of service.  Thus PCBs in building materials could remain in those materials (and those materials could remain where they were) until they were removed from service and prepared for disposal.

(First Disclosure: In a conversation with EPA headquarters, I was told the in-service rule was only intended to apply to PCBs that had already been disposed of in a manner that did not comply with the PCB regulations. However, I think it’s obvious from the use of the words “in-service” that this current EPA HQ interpretation is inconsistent with a plain reading of the text. In my view it takes a somewhat “strained” interpretation to equate the terms “in-service” with “illegally disposed of”).

Looking beyond the in-service rule, even a casual examination of the current PCB regulations makes it apparent that EPA’s main regulatory focus has been on liquid PCBs, like the ones found in transformers and capacitors. This makes sense when your objective is to limit the further spread of PCBs to the environment – liquids are prone to being spilled and obviously spread much more easily than solids. Objectively, the regulation of PCBs formulated into solid products, like building materials, seems to have been an afterthought for EPA. While its researchers knew about PCBs in building materials, even in the 1970s, EPA’s regulation writers either did not know about them or just decided they weren’t important.

The 1994 proposed use authorization
EPA’s regulation writers finally started paying attention to PCBs in solids in the mid-1990s.  In a prelude to the 1998 PCB Mega-Rule, EPA published an Advance Notice of Proposed Rule Making (an ANPRM) in 1991 requesting comments on a number of issues concerning PCB regulation. In the December 6, 1994 Federal Register, EPA published a summary of the comments received and explained how the agency planned to respond to them.

Many commenters described experiences where PCBs had been unexpectedly discovered in building materials (such as caulk, paint and adhesives) during demolition or renovation projects. These commenters told EPA that removing these PCBs posed a huge engineering, construction and financial burden. EPA responded that it had previously been unaware of this problem, but was now proposing a solution to this unintended consequence of the PCB regulations. A few pages later, in the very same 1994 Federal Register volume, EPA proposed a new use authorization, 40 CFR 761.30(q), to legally authorize the continuing use of PCBs incorporated into solid building materials.

In the preamble to the proposed change EPA explained its rationale for the new use authorization this way:

“While the continued use of unauthorized pre-TSCA materials is a violation of the existing PCB regulations, in most cases the premature removal of the media containing PCBs could only be achieved with great difficulty and at enormous expense given the extraordinary efforts that would be required to remove the PCBs.” (Emphasis added).

So as of December 1994, the stage was set for the adoption of a new use authorization for PCBs in solid building materials. But, as one of my old bosses liked to say, “There’s been many a slip between the cup and the lip”. When, four years later, EPA finally promulgated the 1998 PCB Mega-Rule the proposed use authorization for PCBs in building materials was missing. What happened? The only explanation on offer was found at the end of the 1998 Mega-Rule preamble:

“Finally, EPA is deferring regulatory action on proposed 761.30(q) for future rule-making”. . . . “Although EPA received many comments supporting the proposed authorizations, many commenters wanted EPA to drop many, if not all, of the proposed authorizations. EPA needed additional time to review the recently submitted risk assessment studies and also to obtain additional data for certain uses in order to reduce the uncertainties associated with the available studies.”

Since it is almost 20 years later, do you think it would it be impolite to ask whether these uncertainties still exist? In a conversation with EPA headquarters a few months ago I was told not to expect a use authorization for PCBs in building materials any time soon.

So what exactly are the uncertainties EPA is concerned about? And how do they relate to PCBs in schools?

(Second disclosure: This the end of the historical account. The rest of this post is based on my research and opinions).

We know a lot about PCBs. In fact they are among the best studied of all the man-made environmental contaminants. There are 209 different individual PCB chemicals, known as congeners that make up the PCB group; we know all their molecular weights, volatilities, and many of their other physical properties. We divide them into dioxin-like and non-dioxin like categories based on the way they interact with biological receptors, which has also been studied in depth. There are elaborate risk assessment models that claim to assess the level of risk based on just which particular combination of the 209 congeners are present. Every week there is a new research paper published about PCBs with even more information.

What is probably more important is that we know the average concentration of PCBs in the environment and in people has been dropping significantly since the 1970s. We know that the average daily and annual doses of PCBs people receive has also declined significantly. And of course we know that despite their significant efforts, scientists have not been able to tease out any consistent evidence of adverse health effects in people exposed to PCBs in building materials.  Remember, consistent reproducible results is the most important factor separating good science from bad science.

The question I set out to answer with this post was: If there is nothing in the statute or the regulations about removing PCBs from schools or other buildings, and if there is no evidence that PCBs in building materials pose a health risk, then what explains the need to assess and remove PCBs from schools?

Because, after all if Congress were inclined to pass legislation, or if the EPA were going to promulgate regulations that would cost communities and public school systems billions of dollars, don’t you think there would be a cost-benefit analysis somewhere? Before new federal regulations come into being, there is supposed to be a rigorous assessment of potential negative and positive impacts – for the very purpose of avoiding costly unintended consequences. So um, what happened here?  Because there never was a cost/benefit analysis; there never was an honest discussion with the public about risks, costs and potential benefits about regulations that could collectively cost communities hundreds of billions of dollars.

Reluctantly, the conclusion I’ve come to is that there are no good answers to my questions.  My best guess is that most EPA researchers and independent scientists would rather not be the ones to point out that the emperor has no clothes; but the facts are that the fear of PCBs in buildings is without scientific foundation. But at the cost of millions of dollars per building incurred to our school budgets unnecessarily, isn’t it time to to pay attention to the real science?

Final thoughts
Last July EPA issued new guidance for schools and other buildings that may contain PCBs. While the preface contains disclaimers that the new guidance is not intended to replace the requirements of the PCB regulations or TSCA, after reading them one could be forgiven for thinking that this was pretty much what they were supposed to do. The guidance recommends a sensible Best Management Practices (BMP) approach to managing known or suspected PCBs in buildings and downplays the need or desirability of testing building materials for PCBs.

It’s unlikely that this new guidance will be codified into regulations any time soon, but it is helpful for EPA to soften its guidance and it hopefully signals a more rational approach to the issue of PCBs in buildings going forward.


Postscript: OTO just changed its web host, which led to some confusion in the posting of this article.  We apologize for any inconvenience.