Asphalt Table 6

http://ntp.niehs.nih.gov/go/17040

Table 6. Summary of mutagenicity data for asphalt and coal-tar pitch fume condensates*

Source of fume condensates		163	221	232	316	MI^†
		Fume generation temperature (°C)

Roofing asphalt^‡	No.2	---	---	+	---	12 (1)
	No.2	---	---	---	+	10 (1)
	No.3	---	---	+	---	12 (2)
	No.3	---	---	---	+	10 (1)

Paving asphalt^**		+	---	---	---	14^††

		---	+^‡‡	---	---	18^§§(13)

Type I Coal tar pitch		---	---	+	---	725 (35)

		---	---	---	+	1555 (75)

^* Adapted from Machado et al. [1993].

^† The slope of the dose-response curve, i.e., revertants per ml of dosing solution (± asymptotic standard error).

^‡Two Type III roofing asphalts representing different crude sources were used. One of the roofing asphalts was air-blown using ferric chloride as a catalyst (no. 3) and the other was air-blown without the use of a catalyst (no. 2).

^** Eighteen samples of paving asphalt fume condensates representing 14 crude oil sources and various process conditions were used.

^†† Mean of 37 experiments on 17 paving asphalt samples. One to three experiments were run for each sample; MIs ranged from 5 to 49, and the MIs for the pooled data ranged from 6 to 29.

^‡‡ One paving asphalt was generated and tested at 221°C.

^§§ Mean of three experiments.

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