The WHO has been carefully monitoring both epidemiological and animal studies and has come to the following conclusions in a report which it released in 1991: "A study of cancer incidence in Connecticut, USA, over a period of 35 years failed to show a relationship between the use of asbestos-cement pipe and the incidence of gastrointestinal cancer. A further study published in 1980 also found negative results. There is also no conclusive evidence from animal toxicological studies to date that ingested asbestos is carcinogenic (despite the frequent use of high doses). In addition epidemiological studies conducted to date provide little evidence of an association between asbestos in public water supplies and cancer."

The WHO reaffirmed in 1993 its position on the subject:
“There is no consistent evidence that ingested asbestos is hazardous to health and thus it was concluded that there was no need to established a health-based guideline value for asbestos in drinking water.”

In the United States, the EPA has recently determined that:
"EPA does not believe that installed A/C Pipe should be replaced or that its use should be discontinued."