Wednesday, August 1, 2007

Asbestos and its health effects

Is asbestos really that dangerous?

Unfortunately, yes, asbestos is pretty darn dangerous if it finds its way to your lungs.

Those most at risk are the people handling asbestos (think of the unprotected construction workers) although anyone living or working in an environment where friable asbestos is floating around is also very much at risk.

Protecting our kids from the dangers of asbestos should be one of our priorities and the following explains, in details, the health risks of this natural mineral.

What is asbestos?

Asbestos is the name given to a number of naturally occurring, fibrous silicate minerals mined for their useful properties such as thermal insulation, chemical and thermal stability, and high tensile strength.

The current Federal definition of asbestos is the asbestiform varieties of: Chrysotile (serpentine); crocidolite (riebeckite); amosite (cummingtonite/grunerite); anthophyllite; tremolite; and actinolite.

Some past and present uses of asbestos

  • Cement Pipes Laboratory Hoods / Table Tops Elevator Brake Shoes
  • Cement Wallboard Laboratory Gloves HVAC Duct Insulation
  • Cement Siding Fire Blankets Boiler Insulation
  • Asphalt Floor Tile Fire Curtains Breaching Insulation
  • Vinyl Floor Tile Elevator Equipment Panels Ductwork Flexible Fabric Connections
  • Vinyl Sheet Flooring Caulking / Putties Cooling Towers
  • Flooring Backing Adhesives Pipe Insulation (corrugated air-cell, block, etc.)
  • Construction Mastics (floor tile, carpet, ceiling tile, etc.)
  • Wallboard Heating and Electrical Ducts
  • Acoustical Plaster Joint Compounds Vinyl Wall Coverings
  • Decorative Plaster Spackling Compounds High Temperature Gaskets
  • Textured Paints/Coatings Roofing Shingles Roofing Felt
  • Ceiling Tiles and Lay-in Panels Base Flashing Thermal Paper Products
  • Spray-Applied Insulation Fire Doors Electrical Cloth
  • Blown-in Insulation Electrical Panel Partitions Fireproofing Materials
  • Taping Compounds (thermal) Packing Materials (for wall / floor penetrations)
  • Electric Wiring Insulation Chalkboards

Known health effects of asbestos exposure

Exposure to airborne friable asbestos may result in a potential health risk because persons breathing the air may breathe in asbestos fibers.

Continued exposure can increase the amount of fibers that remain in the lung.

Fibers embedded in lung tissue over time may cause serious lung diseases including (1) asbestosis, (2) lung cancer, or (3) mesothelioma:

  • Asbestosis – Asbestosis is a serious, progressive, long-term non-cancer disease of the lungs. It is caused by inhaling asbestos fibers that irritate lung tissues and cause the tissues to scar. The scarring makes it hard for oxygen to get into the blood. Symptoms of asbestosis include shortness of breath and a dry, crackling sound in the lungs while inhaling. There is no effective treatment for asbestosis.

  • Lung Cancer – Lung cancer causes the largest number of deaths related to asbestos exposure. People who work in the mining, milling, manufacturing of asbestos, and those who use asbestos and its products are more likely to develop lung cancer than the general population. The most common symptoms of lung cancer are coughing and a change in breathing. Other symptoms include shortness of breath, persistent chest pains, hoarseness, and anemia. People who have been exposed to asbestos and also are exposed to some other cancer-causing product, such as cigarette smoke, have a greater risk of developing lung cancer than people who have only been exposed to asbestos.

  • Mesothelioma – Mesothelioma is a rare form of cancer that is found in the thin lining (membrane) of the lung, chest, abdomen, and heart and almost all cases are linked to exposure to asbestos. This disease may not show up until many years after asbestos exposure. This is why great efforts are being made to prevent school children from being exposed.

If you feel you may have been exposed to airborne asbestos fibers, you should consider consulting a physician with expertise in pulmonary abnormalities.



Source: EPA's web site

A definition of acid rain

What could be worse than "acid rain", right?

This chemical nightmare, pouring inconspicuously from the skies above, has the power to hurt us (and everything around us) in many nasty ways, hence the importance of understanding it -and- whenever possible, work towards curbing its occurrences.

In a nutshell

"Acid rain" is a broad term referring to a mixture of wet and dry deposition (deposited material) from the atmosphere containing higher than normal amounts of nitric and sulfuric acids.

The precursors, or chemical forerunners, of acid rain formation result from both natural sources, such as volcanoes and decaying vegetation, and man-made sources, primarily emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) resulting from fossil fuel combustion.

In the United States, roughly 2/3 of all SO2 and 1/4 of all NOx come from electric power generation that relies on burning fossil fuels, like coal. Acid rain occurs when these gases react in the atmosphere with water, oxygen, and other chemicals to form various acidic compounds.

The result is a mild solution of sulfuric acid and nitric acid.

When sulfur dioxide and nitrogen oxides are released from power plants and other sources, prevailing winds blow these compounds across state and national borders, sometimes over hundreds of miles.

Wet Deposition

Wet deposition refers to acidic rain, fog, and snow.

If the acid chemicals in the air are blown into areas where the weather is wet, the acids can fall to the ground in the form of rain, snow, fog, or mist. As this acidic water flows over and through the ground, it affects a variety of plants and animals.

The strength of the effects depends on several factors, including how acidic the water is; the chemistry and buffering capacity of the soils involved; and the types of fish, trees, and other living things that rely on the water.

Dry Deposition

In areas where the weather is dry, the acid chemicals may become incorporated into dust or smoke and fall to the ground through dry deposition, sticking to the ground, buildings, homes, cars, and trees.

Dry deposited gases and particles can be washed from these surfaces by rainstorms, leading to increased runoff. This runoff water makes the resulting mixture more acidic.

About half of the acidity in the atmosphere falls back to earth through dry deposition.


Source: EPA's web site