First thing to know is that PAHs are virtually insoluble in water. That’s why the focus is on whether PAHs in sediment can be a health hazard to people – and PAHs are rarely found to be a cause of concern even in highly urbanized areas. For example, the City of Austin, Texas was worried about whether PAHs in sediments in Barton Springs Pool – a beautiful recreational area in downtown Austin with a spring-fed swimming pool – might pose a health risk to people swimming in the pool. So they requested the US Public Health Service, in conjunction with the Texas Department of Health, conduct a “health consultation” to evaluate whether the City should be concerned about the health of citizens swimming in Barton Springs Pool. The health consultation report, posted here, contains the following conclusions: “We did not find any information to support contention that swimming every day in Barton Springs would result in adverse health effects. Thus, we have concluded that swimming and playing in Barton Springs Pool poses no apparent public health hazard.” The City asked the Texas Commission on Environmental Quality and the US Environmental Protection Agency to review the Health Consultation. Assured by the findings of the Health Consultation, the City re-opened Barton Springs Pool.
Another thing to know is that PavementCouncil.org has taken a hard look at whether sealers applied to paved surfaces are contributing in any significant way to PAHs in sediments. We’ve funded scientists to look at the data the USGS uses to claim sealers are a problem and to look at other data (there’s a LOT of data available for PAHs in sediments!). We’ve funded scientists to collect new data to help answer questions. With a very few exceptions (mostly, samples collected right next to sealed lots) the PAH signature of RTS is not identifiable in sediments. Take a look at the Research page on this web site – there are many links to papers and presentations documenting efforts to identify whether RTS is an important source of PAHs in sediments. PavementCouncil.org has filed a Data Quality Act Petition asking the USGS to cease disseminating their flawed interpretations of the data. The flaws in USGS interpretations of sediment PAH data are further documented in PCTC White Paper 1301.
To try to minimize any possible release of RTS to sediments, PavementCouncil.org recommends that sealer applicators follow our Best Management Practices.