Year: 2011

For a Stormy Season – Stocking an Emergency Food Pantry

December 22, 2011 Laura Carr

Be Prepared.

That’s the motto of the Boy Scouts.

“Be prepared for what?” someone once asked Baden-Powell, the founder of Scouting,

“Why, for any old thing.” said Baden-Powell.

Like the Boy Scouts, I believe in being prepared.  2011 tested the survival skills of many New England families with its particularly extreme weather – heavy snowstorms, tornadoes, and a hurricane.  Hurricane Irene left me with out power and water for 7 days.  The emergency food pantry is where I fell short with my emergency preparations.  Although I had non-perishable foods, I did not have what I needed to make balanced meals.  The goal of this blog post is to give you recommendations to start your own emergency food pantry.

With the the winter season here, now is as great time to get stated. Below you’ll find my emergency food pantry list and an emergency shopping list.  I’ve also included a link to “Emergency Kitchen” a website with recipes for one pot meals that can be made with canned and non-perishable food.  Non-perishable foods are “stable” foods that do not spoil and have a shelf life of several months or even years.  They are foods that can be found in many American home pantries.  The emergency list also contains perishable items that do not need refrigeration and have a shelf life of approximately one week.  These include foods like; bread, fresh fruits, and vegetables.

When planning an emergency food pantry, consider the cooking appliances and tools you’ll have accessible in the event of an emergency.  I have a natural gas stove in my kitchen and a propane outdoor grille, they will both work without electricity.  Matches and manual can and bottle openers are important tools to have on hand for emergency situations. Also consider stocking paper products (napkins, plates, bowls and cutlery) as these will make meal clean-up easier.

When shopping for your emergency food pantry, consider purchasing single serving sizes whenever possible to eliminate the need for refrigeration after containers have been opened.  Emergency food pantries should include a variety of foods for balanced nutrition.  It’s also a good idea to periodically check expiration dates on these food items. Peggy Van Laaned’s PDF, “Safe Food Storage” is an informative guide that’s well worth reading.

Fruits and Vegetables Group

  • Canned vegetables (choose low/no sodium to minimize the need to drink water)
  • Vegetable juice
  • Canned tomatoes (juice and sauce)
  • Spaghetti sauce
  • Canned fruit and fruit cups (in natural juice rather than syrupy fruits)
  • Dried fruits (bananas, pineapple, apricots are good examples)
  • Applesauce
  • Fruit juice and juice boxes

Protein Group

  • Canned meat (tuna, salmon, or chicken for example)
  • Canned ham sandwich spread
  • Dried and dehydrated meats (jerky for example)
  • Soups, stews, and chili
  • Baked beans
  • Dried and canned beans and peas
  • Chili Beef stew
  • Peanut butter
  • Nuts

Grain Group

  • Oatmeal
  • Whole grain crackers
  • Breakfast Cereals
  • All pasta types
  • Whole grain rice
  • Whole grain crackers (good replacement for bread)
  • Granola bars
  • Cereal bars
  • Quinoa

Other

  • Water
  • Electrolyte drinks
  • Alfredo sauce
  • Gravy
  • Bouillon cubes (great for flavoring rice and pasta)
  • Dry soup mix (also great for flavoring rice and pasta)
  • Mustard, ketchup, and soy sauce
  • Salad dressing (types that do not need to be stored in refrigerator after opening)
  • Pudding cups (a welcome treat!)

Emergency shopping

  • Bread
  • Fresh fruit
  • Mayonnaise packets
  • Fresh vegetables (that do not need refrigeration: Green beans, broccoli, and brussel sprouts )

Helpful websites:

Emergency Kitchen – one pot recipes for canned and non-perishable foods: http://www.y2kkitchen.com/html/recipes.html

Safe Food Storage – PDF food storage guide:  http://nchfp.uga.edu/how/store/texas_storage.pdf

PCBs: Aroclors, Homologs and Congeners

December 19, 2011 Jim Okun

With PCBs (polychlorinated biphenyls) being more in the news, you may hear the terms “Aroclors”, “homologs” and “congeners” used to describe the different ways that PCBs are measured.  Measuring the concentration of PCBs gets complicated because there are actually 209 different chemicals (referred to as congeners) included in the PCB chemical group.  Measuring all 209 congeners separately is research level analytical chemistry and is impractical for most purposes.  However, analytical chemists have developed a number of effective ways to measure PCBs that don’t require looking for all 209 different PCB congeners.

Measuring PCBs as Aroclors

The most common way to measure PCBs is as Aroclors.  Aroclor was the trade name of the commercial PCB mixtures manufactured by the Monsanto Chemical Company and sold in the United States.  An Aroclor PCB mixture might consist of over 100 different individual PCB congeners, although 10-20 might make up over 50% of the mixture.   When analytical chemists test a sample to see if it has an Aroclor PCB mixture in it, they look for a distinctive gas chromatographic pattern (sometimes called a chromatographic “fingerprint”) that is indicative of one of the Aroclors.  There were  nine common PCB Aroclor mixtures (1221, 1232, 1242, 1016, 1248, 1254, 1260, 1262, and 1268), and each of them has a distinctive gas chromatographic pattern.  Measuring PCBs as Aroclors relies on there being a relatively fixed composition of PCB congeners in the mixture.

When a chemist measures the amount of Aroclor in a sample, they will know the total amount of that Aroclor that is present, but will not know the identity or the concentration of the specific PCB congeners in the sample.  Provided the sample has not been subjected to conditions that might degrade or change the composition of the PCBs, knowing the type of Aroclor present and its concentration is usually sufficient for environmental assessment.

Homologs – For When Sample Weathering Has Occured

However, if an environmental sample has been subjected to conditions that might alter the congener composition of the sample, then it will be more accurate to test the sample by a different method.  Air samples, sediment samples, biota samples and water samples are the ones most likely to have had their congener composition changed by environmental conditions.  This can happen because the PCB congeners with fewer chlorine atoms tend to partition into air and water more readily than those with more chlorine atoms.  For this reason air and water samples are likely to be “enriched” with congeners with fewer chlorine atoms.  Biota samples can also be subject to bio-degradation with some congeners being selectively reduced and others remaining constant.

For samples whose congener makeup has been altered, testing for Aroclors will give erroneous results.  Testing for PCB homologs will give more reliable results for these samples.  Homologs are a way of grouping PCB congeners by the number of chlorine atoms they have; this can vary from one to ten.  All the PCB chemicals that have the same number of chlorine atoms are said to belong to the same homolog group.  There are 11 different di-chloro congeners in the 2-chlorine homolog group and there are 42 different tetra-chloro congeners  in the 4-chlorine homolog group, as examples.  Laboratory results for PCB homologs will list the the amount of PCB present in the sample by the number of chlorine atoms.

But, Sometimes Only Congener Analysis Will Do

In circumstances requiring more congener detail than can be provided by either Aroclor or homolog analyses, it is also possible to analyze samples for a subset of the full 209 congeners.  Analyzing samples for the full 209 congeners is, as I said before, still research level chemistry.  The NOAA PCB congener method cites 20 congeners to be reported, this is often used for sediment analysis. The USACE PCB congener method cites 22 congeners to be reported. The SW-846 8082 method cites 19 congeners to be reported. The WHO lists cites 12 congeners (those which the World Health Organization believes pose the greatest health concern – although this is disputed).  Congener data is particularly useful for forensic purposes, but the guidance available for interpreting the data is fairly limited.

Overall, in most instances measuring PCBs using the Aroclor method will be the best choice.  Where that method is inappropriate, looking at homologs is likely to be a good option, and where even more detailed results are needed, looking for PCB congeners will be necessary.  For homolog and congener testing make sure to select a laboratory with considerable experience with those analyses as they are challenging tests to perform.

For help selecting analytical methods or designing a PCB assessment program, please contact me at okun@oto-env.com.

Mistaken Oil Deliveries – Are You at Risk?

November 18, 2011 Laura Carr

Last year, the Farmers’ Almanac predicted that the winter would “exhibit a split personality, with harsh conditions for the eastern half of the U.S., and milder weather to the west.”  That prediction came true as the Northeast and Great Lakes regions were hammered with many heavy snowstorms.

I usually look forward to each new season.  In Autumn I enjoy putting my garden to bed.  I think of it as an opportunity to clean the slate and prepare for spring’s fresh start.  While I do the work, I daydream about the up-coming winter: the savory scents of home made soups, warm, crackling fires, and the distant sounds of my adult children making snow angels in the yard.   I have to admit I’m not feeling it this year.  The summer was not long and hot enough to erase my 2010 winter memories.

I made a promise to myself to be better prepared for the 2012 winter season.  For me that means plenty of Ice melt and snowblower parts on hand.   What’s on your winter to do list?  Perhaps you’re considering converting from oil heat to gas heat.  If you’re like me, you’ve done a lot of research and you know the conversion can cost between $2000 and $7000.

Last year, NewsCenter 5  compared the costs of heating a 2,500-square foot home with oil using current prices for the 6-month heating season.  If a homeowner used 800 gallons, it would cost about $2,800 for oil heat.  Using an average of 166 units of gas a month, at a cost of $255 per month natural gas would cost a total of $1,350 for the season.  Oil dealers pointed out other factors to consider; not every neighborhood has gas available and they claimed their fuel is a better choice over all because it burns hotter and is more efficient.

If you do make the switch from oil heat to gas heat make sure to remove the oil fill pipe on the outside of our home to avoid mistaken deliveries.  Don’t laugh, I know it sounds ridiculous, but it actually happens and the results are heart breaking.  Just ask Charlie Garnar of Bethpage, Long Island.  The mistaken delivery at his house dumped gallons of home heating oil onto his basement floor.  “From the cleanup, repair on the drywall, getting the smell out of the house – it’s gonna be thousands of dollars, “ said Garnar.

Believe it or not several errors need to occur for a mistaken delivery to take place; a delivery driver unfamiliar with the area, multiple poorly marked residences (snow could play in this part of the scenario), and a home with an oil fill pipe that’s not connected to an oil tank.  Mistakes will happen, but an oil fill pipe that is not connected to anything?  I wondered who was responsible for removing this during the conversion.

I contacted the National Grid who directed me to the conversion section of their website.  Although they are not responsible for the removal of the oil fill pipe they had an extensive list of oil tank removal experts who were able to answer my question.  Petroleum Management Services, Inc. in Reading, MA explained “The removal of the oil fill pipe is part of the tank removal process.”  They were all too familiar with the mistaken delivery scenario and pointed out that it happened in 1987 to Boston Celtics assistant coach Chris Ford at his Lynnfield, Massachusetts home.  According to reports, Ford’s oil fill pipe had been disconnected for approximately 12 years.

For the winter of 2012 the Farmers’ Almanac forecasts “clime and punishment, a season of unusually cold and stormy weather.”  For some parts of the country, that means frigid temperatures; while for others, it will mean lots of rain and snow.   I’m good with the “above-normal” temperatures expected in the eastern U.S.  Just to be on the safe side, I’m heading out to the hardware store to get prepared.  For those of you making the switch from oil heat to gas heat this season – remove that oil fill pipe.

Mexican Chocolate Cookie Helps End Homelessness

November 4, 2011 Laura Carr

Looking for a great Holiday gift idea?

In the slow period after lunch, a coworker and I have started trading cookies at work.  I introduced him to my all time favorite cookie; the one that makes me feel like Homer Simpson when he’s thinking about doughnuts.  The Red Barn Coffee Roasters Raspberry Shortbread cookie is that good.  It’s a buttery shortbread cookie filled with the perfect amount of raspberry jam.  Each bite is pure delight.

Earlier this week, Bruce gave me a cookie from a party he and his wife had attended over the weekend and it was fantastic!  Bruce and Maria had shared their cookie, but I had greedily gobbled down mine without a thought for my husband.  It was a Mexican Chocolate Cookie made by the Dancing Deer Baking Company.  This cookie is a real treat.  Each cookie is individually packaged and tied with a bow so that it makes a great simple gift or party favor.  Truly, I was thrilled to receive it.

The clever packaging tells the story of the cookie and it’s not what you’d expect.  Dancing Deer’s Sweet Home Project helps homeless families find jobs and homes of their own by providing funding and support for homeless mothers to finish their education.  It helps parents transform their lives by attaining economic self-sufficiency.

The Sweet Home Project is an alliance between Dancing Deer and One Family, Inc.  Dancing Deer donates 35% of its Sweet Home product line retail revenues to these efforts.  One family is a nonprofit organization created by the Paul and Phyllis Fireman Charitable Foundation which is committed to ending family homelessness and promoting self-sufficiency nationally.

The Mexican Chocolate cookie not only tastes great, its adorable house shape completes the packaging story.  It has a delicious, balanced, chocolate spice flavor that’s not as sweet as American chocolate, so if you are not a big chocolate lover, don’t shy away from this cookie.    The hint of spice is similar to gingerbread but not as strong.  Really, it’s a sublime combination.

If you are looking for inexpensive Holiday gifts -these cookies are perfect for teachers, coworkers, and clients.  I have college age kids, these cookies will help stretch their tight Holiday budgets.

What a Storm!

November 3, 2011 Jim Okun

For those of us living and working in the Connecticut Valley between central Connecticut and central Massachusetts  the past week has been something out of the Twilight Zone.  Last Saturday afternoon I was sitting at my home computer preparing the write-up of the PCB presentation I made at the UMass Soils Conference.  At about 4 PM, the lights blinked once, the computer screen went dark and all the electricity disappeared from north central Connecticut.

The freak pre-Halloween snow storm has caused a remarkable amount of damage; much more than hurricane Irene did in our area.  So this year  we’ve had a tornado, a hurricane, a minor earthquake and now an October Nor’easter.   Hopefully that’s all the strange events nature has planned for us this year.

From what I have heard, we may have power back at home by this coming Sunday at 11:59 PM, but who really knows?  I’d like to say thank you to the power companies and all the people out working long days and nights to get us wired-up again.  Yes, there are some whiners out there who believe the power companies aren’t doing enough, but most of the public is deeply appreciative of all the hard work that is going on to restore the electricity we all count on.

So this week we’ve slowed down on the blog as we scramble to get our lives our put back together.  Hopefully by next week things will be back to normal.

Update – Connecticut Remediation Regulations Transformation

October 27, 2011 Paul Tanner

Transforming CT’s Cleanup Regs. – Problems and Opportunities

There is a consensus among stakeholders working with Connecticut’s environmental cleanup programs that change is needed. The rigid framework of the Remediation Standards Regulations (RSRs) combined with DEEP’s lack-luster support for the LEP program and a reluctance to accept site-specific risk assessment has resulted in bogged down remediation programs. This regulatory bottle-neck may be contributing to the slow the pace of the state’s economic recovery.

Under CEEP Commissioner Dan Esty’s vision and Graham Steven’s management, I participated in one of six workgroups set up to tackle questions including: evaluating the effectiveness of the current 16 remediation programs; incorporating liability relief into the remediation system; and surveying successful programs in other states. This was public participation on a grand scale and a great value to state’s taxpayers – six workgroups of 16 people, that’s 96 stakeholders (representing business, industry, legal, environmental groups, consultants/LEPs, and government) contributing their 1,400 years of collective experience to the task of clarifying problems and offering solutions. Each group has met five or six times, and together expended over 3,000 hours of effort in five weeks. At normal billing rates, I’d estimate the professional effort donated to the State of Connecticut during this exercise to be worth over $400,000.

Click on this link to read the Remediation Transformation Work Group reports, see the summary of the problem and an attempt at proposed solutions.

Common threads that run through the workgroup recommendations include:
1. The current system is not working in a manner that benefits the citizens; the Transfer Act is particularly problematic and needs to be fixed.
2. Moving to a unified system has clear benefits.
3. A revised system needs to have site specific risk-based on-ramps and exit points.
4. Other states have successful risk-based models to emulate.
5. Incentives must be included to help unclog the system, protect the environment and re-vitalize the real estate market.

Don’t let Connecticut’s best value go unread. Download the six reports to your Kindle and read up on them this weekend. In a future post, I’ll key – out sections which I found illuminating. Do you have experience with other programs in other states that work well to remediate sites to a reasonable and risk-based level of protection of public health and the environment? Now is the time to have your voice heard. The public comment period on the reports ends on November 7. The DEEP is inviting comment at DEP.Cleanup.Transform@ct.gov .

OysterFest 2011

October 21, 2011 Laura Carr

Without question, Wellfleet is my favorite place on earth.  Located on the tip of Cape Cod, It is a friendly town, rich in quaint seaside character.  Since more than half of Wellfleet’s land area is part of the National Seashore, you can expect to find some of the most beautiful beaches on Cape Cod. Even more popular than the beaches, are Wellfleet’s abundance of oysters.

The Wellfleet OysterFest is an oyster lover’s dream come true.  The annual two-day festival takes place the weekend after Columbus Day. Tents and oyster shuckers line Main Street and the two large parking areas in the center of town.  OysterFest brings together locals and visitors alike for a weekend of fun featuring something for everyone: local cuisine, educational lectures, cooking demonstrations, arts and crafts, children’s activities, live music, road races, walking tours, and the Oyster Shuck-Off competition.  My favorite local studio, The Jewelry Studio of Wellfleet, had a tent featuring unique jewelry created by Jesse Mia Horowitz, a local Wellfleet woman.  Out of all her beautiful pieces, my favorite is an oyster pendant, which she casts out of silver using a real Wellfleet oyster as a mold.  The food choices range from chilidogs, and burgers, to fresh shucked oysters, home made chowder and Arnold’s famous fried oysters. Winslow’s Tavern, a restaurant located in the heart of Wellfleet, serves some of their best menu items at a low price to guests who pack into the outdoor area.

The Oyster Shuck-Off takes place on the main stage behind Town Hall.  Contestants are given 24 oysters to shuck as fast and elegantly as they can.   Controversial rulings have been known to fire up the crowd of thousands, as devastating time penalties are added for broken shells, massacred oysters, and blood shed from slashed fingers.  Contestants are the fastest shuckers in the area, and include Wellfleet’s commercial fishermen and chefs from near and far.    It is fun to see different shucking techniques used by the competitors.  This year, Anton Christen of Boston’s Union Oyster House brought a special shucking rock, which he used to help slam his shucker into the side of the oyster.  There were also some friendly rivalries between some of the local seafood suppliers.  A shucker from Mac’s Seafood competed against a shucker from Hatch’s Fish Market to determine which place really shucked the best oysters.  Adventurous members of the audience had to dodge flying shells in hopes of bidding on trays of the briny delicacies and eating a piece of oyster history.

At one point, someone dressed as a golden scallop rushed the stage and entertained the audience with silly dance moves as they waited to hear the results of the first competitors.  The winner of the Shuck-off earns a $1,000 cash prize and qualifies to complete in the National U.S. Oyster Shucking Championship in St. Mary’s County, Maryland.  James Gray, who gracefully shucked 24 oysters in just two minutes and twenty-nine seconds, completed this year’s fastest shuck time during Saturday’s qualifiers!

Out of all the fun and festivities, I think my favorite part of OysterFest is Wellfleet’s dedication to the environment that supplies them with their famous oysters.  One key focus of the festival is to educate the public about the critical role oysters play in a healthy ecosystem.  Many educational tents could be found that featured interactive ecosystems for kids (and adults) to explore.  All oyster-eaters are asked to recycle their shells so that Wellfleet can dump them all back into the ocean.  This helps the reproduction of more oysters, in fact recyclers expect to create between three and seven times more oysters just by putting used shells (which carry valuable nutrients) back into the water where they came from.  Recycling also helps the promotion reef development in the area, which helps control erosion and provides habitat for many sea creatures.  Recycling oysters even the helps filter the water!  Adult oysters filter several gallons of water per hour, which removes particles and pollutants from the water.  Check out this PDF for more detailed information on why it’s important to recycle your shells!  It is so inspiring to see a town working together to create a healthier ecosystem in their waters.  The size of the shell recycling bins was unfathomably heaping, which brought a tear to this OysterFest-er’s eyes.

If you’re looking for a fun, educational, and delicious weekend outing, pack yourself up and get to Wellfleet’s OysterFest next year!

Does Breathing PCBs have the Same Effects as Ingesting Them?

October 14, 2011 Jim Okun

In schools and other buildings where there is concern about exposures to PCBs, inhalation of contaminated air is usually the exposure pathway of greatest concern.  However, few, if any, laboratory studies have specifically considered whether the inhalation of PCBs results in the same or different health effects than those observed when PCBs are ingested.

In their risk assessment models, the USEPA assumes that exposure to PCBs by all routes of exposure are toxicologically equivalent.  Since most or all of the animal toxicity studies used to assess PCBs have been feeding studies (using the ingestion pathway), this is the mode of exposure that we know the most about.  However, there are some good reasons to suspect that inhalation exposures may be different from ingestion due to the way PCBs behave once they enter the body.  This is particularly true because the liver is one of the principle target organs for PCBs.

When any toxic material is ingested (or a pharmaceutical product for that matter) absorption usually begins in the stomach and is generally completed in the small intestine.  As chemicals are transferred into the circulatory system from the digestive organs, their first destination in the body is the liver.  So if a chemical gives rise to liver toxicity, ingestion can be a particularly damaging route of administration because the toxic material proceeds directly to the liver from the digestive tract.

By contrast, when a toxic material is inhaled, it enters the lungs, transfers to the blood, goes to the heart and from there enters the general circulatory system.  By the time an inhaled toxic material reaches the liver, its concentration has been reduced by dilution into the overall volume of blood in the body.  What’s more, in the case of lipid (fat) soluble chemicals like PCBs, a high percentage of the dose entering the body by inhalation will become sequestered in other fatty tissues before the PCBs ever reach the liver.  The overall effect would be to reduce the potential toxicity to the liver.

Interestingly there are pharmaceuticals that exhibit similar effects, testosterone is a good example.  When used as a pharmaceutical, testosterone can not be given orally, that is by ingestion, because it can cause liver toxicity. This is despite the fact that it is a naturally occurring hormone.  However, when given by routes of administration that reduce the concentration that the liver sees at any one time, testosterone does not harm the liver.

At this time I am not aware of good animal studies that test whether inhaled PCBs are in fact less toxic than ingested PCBs.  However, there are a large number of well documented human studies where people were exposed to PCBs by inhalation in occupational settings.  These studies consistently show less toxicity than has been predicted by EPA’s health effects models.  It could be that this lower than expected toxicity is due to inhalation being the exposure pathway for these people rather than ingestion.  If this is true, then it supports the idea that low concentrations of PCBs in air may be less hazardous than thought.

Leaf Peeping in New England

October 7, 2011 Laura Carr

Thinking of “leaf peeping” this weekend but don’t know where to go?  The US Forest Service recently launched its expanded Fall Colors 2011 and the site is jam packed with information about one of nature’s most spectacular seasons.  Within minutes I had all the information I needed to plan a weekend adventure of leaf peeping.

The Fall Colors website includes clickable maps that link to forest-by-forest fall color information, state tourism, and fall color websites.  It also offers a variety of family activities like finding direction without a compass, how to make leaf and bark rubbings, and how to make a waterscope.  Waterscopes are a simple, but very useful tool that allows you to easily see the life taking place in shallow streams and ponds.

You can also access the latest foliage updates at the Fall Colors Hotline – 1-800-345-4595.  The hotline provides audio updates on the best places, dates and routes to take for peak viewing of fall foliage in national forests.

The hardest part for me will be deciding between a road trip to the White Mountain National Forest in Woodstock, New Hampshire via the Kancamagus Highway  or a trip along the Connecticut River byway in Vermont.   Either way, I’m sure it will be a good choice!

Coplanar (aka “dioxin-like”) PCBs

October 5, 2011 Jim Okun

Polychlorinated biphenyls (PCBs) are an environmental contaminant in the news  because they have been discovered in schools and other buildings.  PCBs are actually a mixture of many different similar chemicals; there are 209 chemically different chlorinated biphenyls that together make up the PCB chemical group.   If you spend time learning more about PCBs, a term you may run into is “coplanar PCBs” sometimes also referred to as “dioxin-like PCBs”.  Neither of these descriptions are really scientifically accurate, but they have stuck anyway.

Chemically, coplanar PCBs usually refer to 12 of the 209 possible PCB molecules that do not have a chlorine atom stuck in what organic chemists refer to as the “ortho” (or number 2 or 6) position (typically the mono-and di-chloro PCBs are not counted as being coplanar).  The absence of an ortho-chlorine atom allows the biphenyl molecule to get closer to being a “flat” molecule; that is one with all 12 carbon atoms lying in a single plane; thus coplanar.   Of the 12 chlorinated biphenyls generally considered to make up the coplanar PCB group, 8 are generally absent from commercial PCB mixtures.   Based on pioneering analytical work by George Frame at GE’s R&D Laboratory, we know that the total sum of coplanar PCBs in commercial PCB mixtures is well less than 1%.

The reason coplanar PCBs are also referred to as “dioxin-like” is that they have some ability to bind to the same biological receptor protein molecule that dioxin binds to.  Other common environmental contaminants, such as the polycyclic aromatic hydrocarbons (PAHs) also bind to this biological receptor.  The ability to bind to this receptor does not mean that either PAHs or PCBs have the same type of toxicity or the same potency as dioxin.

The World Health Organization has concluded that certain of the coplanar PCB molecules should be treated as if they were less potent versions of dioxin; the USEPA seems to agree.  The relative “toxic potency” of the coplanar PCBs  is quantified using Toxicity Equivalence Factors (TEFs).      The USEPA and other regulatory agencies routinely require that testing be conducted so that the amount of dioxin equivalent toxicity of wastes and dredge spoils can be calculated.

The TEF approach is not without its critics.  There is in fact considerable scientific controversy about the application of TEFs to coplanar PCBs.  In a number of cases the use of TEFs has been shown to significantly overstate actual toxic hazards.