This article explains the potential health hazards (asbestos exposure by ingestion) as well as practical problems (fragility, collapse, expense of replacement) of cement asbestos transite pipe water piping and we provide citations to authoritative studies of this question. This document assists building buyers, owners or inspectors who need to identify asbestos materials (or probable-asbestos) in buildings by simple visual inspection.
We provide photographs and descriptive text of asbestos insulation and other asbestos-containing products to permit identification of definite, probable, or possible asbestos materials in buildings.
Transite pipe or asbestos-cement pipes were used for water supply systems in some municipalities up into the 1970's in the U.S. and probably in other countries. In some cities (Ellwood PA for example), the transite water mains were found to be unable to reliably withstand high water pressures (up to 225 psi in Ellwood according to one of our readers) and the pipes were easily broken.
Asbestos fibers may be ingested from water supplied through transite water piping. Transite piping deteriorates over time, releasing asbestos fibers from the interior of the pipe into the drinking water flowing through that conduit. The level of health risk from ingested asbestos fibers is uncertain and probably low. An NIH report prepared by industry experts concluded:
The work group believes that the cancer risk associated with asbestos ingestion should not be perceived as one of the most pressing potential public health hazards facing the nation.
However, the work group does not believe that information was sufficient to assess the level of cancer risk associated with the ingestion and therefore, this potential hazard should not be discounted, and ingestion exposure to asbestos should be eliminated whenever possible.
Another study by Millette JR et als reported
Cancer mortality for the population census tracts of Escambia County, FL, which use asbestos-cement (AC) pipe for public potable water distribution, was compared with cancer mortality data collected from census tracts in the same county where other types of piping materials are used. An analysis of covariance was run to test for differences in standard mortality ratios for seven cancer sites among three potential asbestos exposure groups based on AC pipe usage.
Twelve variables representing nonexposure-related influences on disease rates were combined in four independent factors and used as covariates in these analyses.
No evidence for an association between the use of AC pipe for carrying drinking water and deaths due to gastrointestinal and related cancers was found. The limitations on the sensitivity of the analysis are discussed.
- ASBESTOS DUCTS, HVAC - Guide to Identification of Asbestos Materials On or In Heating and Cooling Duct Work: carbon monoxide hazards of transite chimneys and vents
- TRANSITE PIPE AIR DUCTS - Hazards of Asbestos-containing Transite Pipe HVAC Ducts: duct collapse, mold, radon, asbestos fiber release
- TRANSITE PIPE CHIMNEYS & FLUES - Guide to Identifying Asbestos Transite Chimneys & Flues & their Hazards in buildings
- TRANSITE PIPE WATER SUPPLY PIPING - Guide to Identifying Asbestos Cement Transite Water Pipes & their Hazards in buildings
While an expert lab test using polarized light microscopy may be needed to identify the specific type of asbestos fiber, or to identify the presence of asbestos in air dust or water samples, many asbestos-containing building products not only are obvious and easy to recognize, but since there were not other look-alike products that were not asbestos, a visual identification of this material can be virtually a certainty in many cases. Links to U.S. government and other authoritative research and advice are included.
A more immediate water quality hazard has been detected in some vinyl-lined transite water pipes - Tetrachloroethylene. A report on the Sandwich water district on Cape Cod in Massachusetts reported that
"PCE was detected in the distribution system at an annual average of 0.8 parts per billion, which is below the limit set by the U.S. Environmental Protection Agency (EPA). This substance leaches into the water from vinyl lined transite water pipe. In order to address this problem, in 2002 approximately 8,500 feet of water mains were sealed with an epoxy coating resulting in a dramatic decrease in PCE levels. "
Leaks in transite water supply piping underground can result in substantial water losses in districts where this piping was used.
Locating transite water supply mains: We've been informed that excavators complain that its lack of metal makes locating transite water pipes difficult - one cannot use ordinary metal detectors.
Of course a buried pipe of non-metallic material might be located if it is possible to insert a sending probe inside its length but on a water main this procedure is impractical. Contractors joke that they find transite pipe by using the metal bucket of a backhoe as a pipe detector.
Replacement costs for transite water supply piping: because of its age, leaks, fragility, and difficulty of finding transite cement asbestos water supply mains and water piping without also damaging it at the same time, owners of properties and communities served by cement asbestos water pipes (transite) can expect to face increasing costs to replace that piping.
Asbestos fiber release hazards during removal of demolition of transite piping are discussed
at TRANSITE PIPE CHIMNEYS & FLUES.
at TRANSITE PIPE CHIMNEYS & FLUES.
Incorrect spellings of transite piping or transite duct material that we've seen include transit pipe, transit ducts, Transide pipe, transide ducts, tranisite pipe, and transight pipe. "Transite" is the correct spelling.