Historically, antimony has experienced a very curious narrative.  Stories excerpted from the National Institute for Occupational Safety and Health (NIOSH) follow:[1]

• In 4000 BC, antimony was used in the manufacture of vases and vessels—no records of adverse effects to the workers.
• About 2000 BC, Egyptians used antimony sulfide in cosmetics to be used as black eyeliner.
• Around 70 AD, the Roman Herbalist and Father of Pharmacy, Pedanius Dioscorides, prescribed antimony as a medicine. The Romans were known to use antimony as an emetic to induce purging (e.g., induce vomiting).
• In 1713, the Italian physician and forerunner of occupational medicine Bernardino Ramazzini  recorded: (1) a chemist exposed to antimony fumes was tormented by a cough which the chemist thought was related to acid vapors; and (2) glass makers suffered vertigo, ulcers in the mouth, esophagus, and trachea, and “consumption” (e.g., body wasting).
• In the early 1900s, typesetter disorders were associated with molten antimony.  The disorders included weakness, intense depression, pallor, palsy-like tremors, bladder and urination pain, temporary impotence (e.g., infertility), dyspnea (e.g., shortness of breath), irritable hyperactivity of the heart, and gastric irritation.  Although lead and arsenic components were likely impurities in the antimony, symptoms were not that of lead intoxication.
• Also in the early 1900s, antimony salts (e.g., antimony potassium tartrate and antimony sulfide) used as color fixatives in clothes dyes and in foundries were linked to necrotic dermatitis and scarring.  Antimony was being used to treat tropical diseases as well.

Today, powdery antimony trioxide is primarily used as a flame retardant. As a fire retardant additive, it is not as likely to pose an airborne toxics hazard. However, there are those who would suggest that sudden infant death syndrome may be related to antimony powder leaching from infant flame retardant mattresses.  Other antimony-containing flame retards are used in toys and children’s clothing and in automotive/aircraft seat covers.  Antimony trioxide has also been used in fiberglass resins for light weight, flame retardant aircraft “engine covers.”

The elemental metallic antimony is used in anti-friction alloys (often referred to as Babbitt metal).  Antimony increases hardness and mechanical strength. High temperatures are required to melt metals and turn them into liquids. As metals melt, fumes may or may not be visually apparent (e.g., smoke).  Some other manufacturing processes likely to involve antimony are: (1) lead-acid batteries (Pb-Sb), (2) bullets/lead shot, (3) linotype printing machines, (4) lead-free solder, pewter, and (5) the manufacturing of organ pipes. Antimony is increasingly being used in the semiconductor industry as a dopant to increase processing speed, and it is used in medicine, cosmetics, safety matches, paint, and bubble-free glass.

So, where does this lead us? Sauntering down the road to occupational exposures—elemental antimony, antimony oxides, and antimony sulfides have variant uses and health effects. These aberrations are truly phenomenal.

• Elemental Antimony—silver-colored metal                                                                                                                                                               Elemental antimony is used as a metal alloy and is an irritant of the mucous membranes, eyes, and skin.       

• Antimony Oxides (trioxide and pentoxides)—white powder                                                                                                                                             Antimony trioxide is a flame retardant and causes pulmonary injury. It is also a suspect carcinogen.

• Antimony Sulfides (trisulfide and pentasulfide)—dark gray powder                                                                                                                            Antimony trisulfide is used in fire works and is cardiotoxic.

In brief, the basic use differences are metal alloy verses flame retardant verses pyrotechnics, and the health impact differences are irritation verses pulmonary injury verses heart damage. There have been multiple studies that indicate greater health hazards than those posed herein. Yet, clearly there are aberrant uses and aberrant health effects in the Wild World of Antimony.

Relegated to the back seat of lead and chromium, antimony and antimony compounds pose a threat that is all too often ignored in industry.  Heads up!

Stories of distressed office building and home owners abound. A few case studies worthy of discussion follow:

Case #1: A drunk drove his car through a house, thinking it was his garage—the car was actually in the living room. After the insurance paid for the rebuild of the home and replacement of furnishings, the traumatized home owner complained of sickening odors and illness. Was she crazy or was she a victim? On 60-minutes, Chinese sheet rock was the toxin casualty of the month.  This escalated her concerns. Chemical off-gassing from building materials became an obsession. Family told her she was crazy while friends validated her concerns about a nasty odor. When all effort failed, the process of elimination (e.g., removal of suspect products) brought her to the conclusion that one of the upholstered chairs was off-gassing chemicals.  Analysis would have been more expensive than replacing the chair. So, as the supplier was willing to buy back the furniture, no further analysis was required.  If this had been a manufactured chair that was associated with numerous complaints, product off-gassing analysis would have been indicated.

Case #2: A small business owner alleged that an evil arch enemy was poisoning him and his assistant. Employees who stared in disbelief were quickly identified as saboteurs.  Hidden cameras were installed in hallways. A private investigator was hired.  Troubled employees left or were forced to resign. Stinky clothes were sent to a lab with requests to identify the “stink.” The chemical laboratory declared the stinky clothes unmanageable.  After all this, Omega Southwest Consulting became the last-call-hurray.  After considerable discussion and chasing demons, we identified the problem as sewer gases from leaks in the bathroom vents within the attic being drawn through the ceiling tiles spaces by the HVAC air return into the office spaces.

Case #3:  A home owner complained of a foul odor and that she was getting sick in her house.  As a result, she had to either sleep outside or move in with her daughter’s family. She spent a fortune on questionable plumbers and “psychics.” She had the state department of health investigate.  They found nothing.  She had the county sanitarians check her septic system.  They found nothing. She called a chemical laboratory to check it out.  They took a soil sample for metals and found nothing. Omega Southwest Consulting, once again, became the last-call-hurray. Multiple problems were identified.  The 1930’s house had cast iron sewer lines in the house. Over time, cast iron  sewer pipes corrode, rust, and leak sewer gases—which were evident around certain areas of the house. The “conventional” septic system was in the back yard where she had planted very happy, healthy trees—root penetration and plant fertilization into the septic lines.  Furthermore, the potable drinking water was crossing the septic field.  She and her granddaughter complained of stinky water.  The home owner was of modest means and could not afford the fix.  Therefore, she moved out.

The above case studies are only a few of the many.  Oftentimes, plumbing/sewage problems are illusive and seem to migrate, structural problems go unidentified, and the HVAC, the heart beat of a structure, remains out-of-site, out-of-mind. Not everyone smells the odors or experiences the illness that others do.  Indoor stink is complex and not for the faint of heart….

Forest fires, residential fires, and building component fires remain on the backburner of public concern. Insurance companies, fire clean-up crews, and construction workers are generally focused on the immediate problems at hand while ignoring the potential impact of toxins in the aftermath of extensive fire damage.

Forest fires can leave a wake of human tragedy that extends well beyond the obvious forest and residential damage. That tragedy is the release of toxins that have no immediate affect on the health of those exposed, therefore no immediate concern or precautions. Yet, several years later, the story book may change. This was the case of asbestos exposure and, although unconfirmed (presently under litigation), the Twin Tower’s toxins.

Now, the Texas Bastrop Wildfire that occurred in September 2011 resulted in the damage of 34,000 acres of land and 1,400 homes, and once again, the main concern is to restore people’s homes. The concern for that which you can not see or that which has no immediate health effects has not been an overriding consideration. That said, let’s look at the potential toxic releases in a discussion regarding: (1) forest fires; and (2) residential fires.

First, forest fires result in the release of dioxins, one of the most toxic substances known to man. Dioxins are a group of compounds, the most toxic of which is 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD).  2,3,7,8-TCDD is one of the most carcinogenic compounds known man. If one ascribes a toxicity level of 1 to 2,3,7,8-TCDD, the other dioxins range in relative toxicity from 0.1 to 0.0001 (as determined by the World Health Organization).[1]

Second, residential fires are not without the release of toxins.  During a fire, thermal decomposition of building materials, light bulbs, appliances, furniture, and cleaning/maintenance products can result in a medley of toxins—some of which will settle in the dust, soot and debris while other more volatile (e.g., gaseous) will dissipate into the atmosphere.

In the Twin Towers, the most offensive toxin generated from the building materials was asbestos. The source was asbestos-containing thermal insulation. Very few older residences had asbestos-containing thermal insulation, but asbestos shingles and asbestos siding were common in houses up to 1978. The more recent, modern homes are unlikely to have had asbestos construction materials. Public awareness of asbestos health hazards and the phased-in ban on asbestos building materials in residential construction have resulted in its limited use, and in newly constructed homes, asbestos exposure concerns following a fire are minimal. There are, so to speak, bigger fish to fry.

Burned copper electrical wiring, plumbing, and mechanical air handling coils will result in airborne copper fumes which will ultimately settle in the dust, soot and debris in the aftermath of a fire. Many paints have toxic heavy metal components as well. For instance, lead-containing paints which were banned in 1978 in residences were in common use in high quality exterior paints, and there is lead in car batteries. Arsenic has been used as a pigment, wood preservative (e.g., Wolmanized® treated lumber), and anti-fouling agent (e.g., paint on boats). Mercury, cadmium, and chromium were used as pigments and preservatives.

Some woods are treated with toxic pentachlorophenol (PCP) which will thermally decompose to unknown gases and is suspect of containing dioxins. Toxic chlordane and other household pesticides are also likely to decompose to gaseous toxics and likely to dissipate into the atmosphere, or the gases may be trapped and retained within the carbon soot.

Roof and sheathing particleboard glues may thermally decompose to release gaseous formaldehyde, phenol, and unpredictable toxins resulting from the thermal decomposition of the building components. Whereas the gases are likely to dissipate, heavy metals are more likely to settle in the dust, soot and debris.

Even as newer building materials are entering the marketplace (especially in green energy construction), thermal decomposition of some of the newer, synthetic products may have a few toxic surprises (e.g., recycled compressed and glued woods). And the list goes on.

There are unintended consequences connected with energy-efficient fluorescent light bulbs. All things containing mercury will, not might, result environmental contamination. Normally, fluorescent light bulbs are recycled, but this becomes impossible when broken or damaged in a fire. Fluorescent light bulbs have 1.5 to 35 milligrams of mercury each. Most homes use fluorescent lights in the garage, kitchen, and workshop. Beyond that modern homeowners that can afford it purchase energy-efficient lights to replace the incandescent lights.

Other sources of mercury include, but are not limited to, thermostats (for heating and AC temperature controls), TV and computer LCD screens, and some older gas-fired appliances. Mercury was further used in anti-mold paints, button batteries, neon lights (as much as 100 to 500 milligrams of mercury each), UV tanning lamps, and some pesticides.

Many of the older light ballasts and outdoor electrical transformers had polychlorinated biphenyls which when they burn (or explode) produce dioxins and furans. Furans are a relative of dioxins. Dioxins are also a byproduct of burned vinyl tiles, many plastics, and foam cushions.[2]

Plastic upholstery and polyvinyl chloride can result in gaseous vinyl chloride and semi-volatile polycyclic aromatic hydrocarbons (PAH). Some of the PAHs are suspect human carcinogens. After a fire, the gaseous and volatile organics dissipate into the atmosphere while semi-volatile organics tend to settle within the soot, debris, and on surfaces.  There are over 50 toxins listed and screened as environmental contaminants of concern. Some of those on the list are phthalates (e.g., plasticizers), pyridine (e.g., cigarette smoke), and naphthalene (e.g., moth balls).

The thermal decomposition of household cleaning and maintenance products, as well as automotive maintenance products and stored paints, can serve up a mixture of unknowns. The possibilities are endless!

Ground Zero Memorial: Toxic Gases

Ten years after the collapse of the World Trade Center, the full impact of the toxic clouds of burned debris is rearing its ugly head.

At the time, first responders, rescue/recovery/clean-up workers, and local residents entered the dust laden atmosphere in the aftermath of the disaster without regard for their safety and/or guidance from health and safety professionals.  No air sampling was performed immediately after the devastation, and limited air sampling was performed on-site by New York state and U.S. Federal agencies. Private health professionals also performed air sampling in areas on the periphery of Ground Zero. Now, ten years later, respiratory illnesses and cancer is on the rise. The conundrum, the illusive truth of toxins is that their impact is frequently delayed. Many toxic exposures involve no immediate warnings. The health effects, particularly that of cancer and lung disease, may be delayed for years.

State and Federal agencies, when they finally began taking air samples, were focused primarily on the obvious—asbestos. At the time of the Fall of the Twin Towers, air monitoring and surface sampling was secondary.  is indicated in all situations involving high temperature burning of buildings, building components and furnishings. Some of the more predictable building components that could release toxic substances are fluorescent light bulbs (mercury), thermal/acoustical sprayed on insulation (asbestos and fiberglass), concrete (silica), light ballasts (PCB burn by-products: dioxins and furans), plastic upholstery (vinyl chloride and polycyclic aromatic hydrocarbons), foam cushions (hydrogen cyanide and dioxins), paint (lead, mercury, and cadmium), stainless steel (chromium), and pesticides. Reports estimated that there had been in the Twin Towers: 

• Greater than 400 tons of asbestos sprayed-on insulation
• More than 10,000 personal computers with over four pounds of lead each
• More than 500,000 fluorescent light bulbs which may contain 1.5 to 35 milligrams of mercury in each light bulb, depending on the size of the bulb (neon lights contain as much as 100 milligrams of mercury)

Beyond those toxins mentioned above, the medley of building components are endless and the incineration by-products will, not might, result in unpredictable unknowns. Although it is not clear as to the full extent of the sampling performed, it appears that the sampling was very limited. 

Based on lung tissue samples taken in 2010, four of seven previously healthy World Trade Center responders who had developed lung disease were found to have carbon nanotubes in their lung. Bulk samples taken from Ground Zero in September 2001 indicated the presence of carbon nanotubes which could cause lung cancer much like asbestos. Some suggest that high temperatures in the presence of carbon and metals could result in the creation of such fibers. Carbon nanotubes were unpredictable.

Ten years later, there are multiple cases of cancer and respiratory illnesses associated with the first responders, rescue/recovery/clean-up workers, and local residents. Law suites are on the rise, and speculation abounds.

Properly planned and executed air monitoring and surface sampling would have provided data that could have provided information to aid in determining the proper personal protection for those exposed and provide historic exposure data that could be taken to the bank.  In this litigious world, speculation is a poor substitute for proper planning and response actions and for proper air sampling. The devil is in the details!