Carcinogen


It’s always fun to hear about new/different situations especially when the contractor handles it properly.

Vermiculite

During the start of a demolition on a 1989 structure, the first swing of the hammer produced a pile of vermiculite sand.

 

 

 

After some discussion on “what in the world is this doing inside a wall cavity“. The contractor stopped work, had an asbestos test performed and quarantined the area. The bulk sampling for asbestos came back with the report of “asbestos containing, but less than 1%“. Well, as you know (and as I have mentioned earlier) it may not be safe to treat this product like every other demolition project. In this case, the asbestos was very friable and by opening the wall cavity, it had definitely been disturbed.  The contractor quickly set up some procedures. Here they are:

  • Stop work in area. Quarantine area and place warning on doors.
  • Train employees & subcontractors onsite to hazard (asbestos).
  • Abatement contractor will remove wall & vermiculite
  • Abatement contractor will treat the material as if it is asbestos containing
  • Once the area is abated. An aggressive clearance test will be performed to assure no airborne levels of asbestos are present.

But why in the world was it in there in the first place? The best guess is it was added as a sound proofing / noise dampening for a air conditioning unit (actually a liebert unit) located on the adjacent wall. No other wall cavities contained the material.

chippingYes, there can be airborne silica in the concrete when you are chipping up motar & tiles from a concrete base. This week a friend told me about his neighbor. He is a self-employed tile setter. He has worked in the industry for 20+ years. They just discovered he has cancer and will have the upper portion of his lungs removed.

Go here for more information. NPR article on silica rule delay.

 

silica4

From what I have seen, there are not a large amount of formaldehyde exposures in construction. However, there is A LOT of formaldehyde used in construction materials. Formaldehyde can be dangerous at levels undetectable by your nose. And, the symptoms of exposure are nondescript (irritant & tingling of eyes, nose, respiratory tract).

Here are some products that may contain trace (or more) amounts of formaldehyde:

  • resins in plywood, MDF, CDX, particle board/fiber board
  • garage doors
  • drywall
  • roofing
  • glues / mastics
  • paint/coatings
  • carpets
  • insulation (spray in and batting)

I believe the reason we do not see high exposures is due to the limited duration of exposure, and the open-aired nature during the construction. Some exceptions are warehouses with large storage areas of particle board/MDF. (I have found exposures in these areas)

The OSHA exposure limit for formaldehyde is 0.75 ppm (action limit of 0.5 ppm, and short term limit of 2 ppm). However, this may not be low enough, based upon other standards (ACGIH says 0.3 ppm, NIOSH 0.1 ppm)

Another major issue with this hazard in construction is once the space is occupied.

  • Once construction is done, the space may be sealed up, heated, and additional curing can occur.
  • This may release more formaldehyde, and also NOT allow as much to escape (by dilution ventilation).
  • Compounding this issue are the type of occupants in the building. Are there children, non-working adults, immunocompromised individuals, sick, or elderly occupying this space? The OSHA standards are NOT protective for these types of people.

I do not forsee this type of sign being posted immediately after new construction.

formaldehydeOn the plus side, someone has discovered that plants may help reduce formaldehyde & VOC levels in homes. Horticulture Science Kwang Jim Kim, et.al

 

CaliforniaProp65 labelYou may have seen a product label which states that, “this product is known to cause cancer”…if used in California. (ha)

Proposition 65 is essentially a labeling rule. in 1986, California made a rule mandating anyone selling to California to label the product… if it had a serious health risk. This rule was above and beyond the OSHA reporting limit of 1%, like on a MSDS (henceforth called SDS, BTW).

The rule is actually good. It makes manufacturers tell you if there is anything hazardous in their product, or if they used anything hazardous when they made the product. (Side: If you haven’t heard, some manufacturers like to hide their ingredients, some say for proprietary reasons. Here’s an example)

More information about the rules is here. There is controversy over it’s usefulness (see here), but in this day in age, I believe you should be made aware of the information.

What usually happens is you find a SDS with no information about the product. Then, as you investigate, you find a “Proposition 65 warning”, indicating something about the product which, “may cause cancer”. So you ask, why does this happen? (more FAQ here) Well, the manufacturer used, or contains, something in their product that is hazardous. It can be a nice trail leading to chemicals which to sample for, or investigate.

When training people who work around asbestos I usually discuss the word “disturbance” for a LONG time. The reason is simple. If you avoid “disturbing” it, you avoid most of the health issues.

As most people are aware, asbestos is found in many types of materials. Floor tiles, popcorn ceilings, wall panels, etc.

Disturbance relates to the specific activities you perform AND the type of material the asbestos is in.

If the asbestos containing material (ACM) is non-friable, then in theory, it takes more effort to disturb the asbestos. If the material is friable, well, you need to be REALLY careful. – and in some cases, breathing can disturb it. For example, an electrician who uncovers an ancient acoustical ceiling panel and finds damaged asbestos pipe insulation laying on top of it…is probably already in trouble. He has essentially disturbed friable asbestos by merely moving the panel.

In contrast, a remodeling company installing a floating laminate hardwood over asbestos 9×9 inch tiles (without damaging them) is [probably*] NOT causing airborne releases of asbestos.

Most of the OSHA/EPA asbestos rules hinge on the matrix of the material and the activity you are performing on it. The reason is this is what makes the asbestos fiber airborne.

*the OSHA rules are very specific as to work activity, please do your due diligence.

You already knew it. There is a lot to do in industrial hygiene. At times this occupation feels like a safety middleman trying to keep people out of trouble. Occasionally I’m rewarded with really helping someone. In the United States, there is still a lot of occupational hygiene issues and concerns. Overseas, particularly in developing countries, there is even more.

It is hard to obtain accurate exposure data, or illness rates, from these underdeveloped countries. (How does a village of 1,000 people in Kenya report that they’ve had lead exposure to battery recycling?) How these exposures are brought to light is by either a massive death (# of people, quickly) or, someone with a camera able to actually photograph the pollution. As we know, what it looks like doesn’t necessarily correlate with hazardous levels of exposure. But, in some cases, it’s pretty obvious.

I ran across this photo story on pollution (The Guardian, UK). They estimate 125 million people are exposed to industrial pollutants (generic term, I know). This makes occupational related exposures a health risk as big as TB and Malaria! The article is based upon a report from the Blacksmith Institute which included this map of the worst pollution with associated disease.

How does this apply to construction? The worst offenders are lead (Pb) (and other metals), and asbestos.

What can you do? Here’s their recommendation, from the report (p50):

Developing countries need the support of the international community
to design and implement clean up efforts, improve pollution control technologies, and provide educational
trainings to industry workers and the surrounding community

Another NPR article about lead poisoning can be found here.

It was recently declared that diesel exhaust is a carcinogen by the World Health Organization’s (WHO) International Agency for Research on Cancer (link to the press release). As you know, a carcinogen is a substance known to cause cancer. The most well known carcinogens are cigarette smoke, benzene, and asbestos.

If you are in construction you probably know how many pieces of equipment use diesel…LOTS. In fact, heavy highway and large commercial construction use it almost exclusively. And, if you have ever traveled out of the US, you realize that diesel is used a lot more than gas. Don’t forget trains and commercial trucks.

So, if you think you have possible exposures to diesel exhaust on a regular basis…you should do something. Here are some ideas:

  • tune-up (lower emissions, better efficiency)
  • direct exhaust away from people/HVAC intake
  • exhaust equipment outside
  • increase dilution ventilation (usually not recommended for carcinogens)
  • make sure the scrubber works
  • measure exposures to employees (ask me in 20 years why this is a good idea)
  • switch to biodiesel (I actually DO NOT know if this is a safe-alternative, but it does smell better)

Here is another article on it.

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