PAHs are everywhere. They occur naturally in organic materials, and are made whenever organic substances are heated. The peer review report of the USGS research team so-called “risk assessment” contains a summary of typical sources of PAHs that everyone is exposed to every day. For example, on the topic of PAHs in food, the report quotes the World Health Organization as follows:
Food is a major source of intake of PAHs for the general population. Estimates of PAH intake from food vary widely, ranging from a few nanograms to a few micrograms per person per day. Sources of PAHs in the diet include barbecued/grilled/broiled and smoke-cured meats; roasted, baked and fried foods (high temperature heat processing); breads, cereals and grains (at least in part from gas/flame drying of grains); and vegetables grown in contaminated soils or with surface contamination from atmospheric fall-out of PAHs…
The point is that PAHs can accumulate in house dust because of every day living (for example, cooking or smoking or smoky fireplaces) or because of products that might contain PAHs (such as flooring glues or coatings or lubricants). Scientists have studied whether people exposed to contaminants via house dust have evidence of those contaminants in their bodies. Results of such studies so far seems to indicate that no, body burdens of people exposed to contaminants via house dust are not significantly elevated relative to those who are not exposed in this way.
People have been “making” – and been exposed to – PAHs since fire was invented. The USGS research team has tried to tie risks related to PAHs in house dust to pavement sealer. See the risk assessment peer review report for an evaluation of how that worked out for the USGS as a matter of science. In its continued advocacy campaign, the press has picked up on the USGS scare tactics, with over-the-top headlines. Via a third DQA Request for Corrections, PavementCouncil.org has documented the exaggerations and unexplained deviations from risk assessment practices used by the USGS and their co-author, affiliated with Baylor University, in their assessment.