Table 3.

Summary of linear least-squares regression analyses for various comparisons.

Basic analyses	No. of compounds included	No. of data points included	Regression line	R2 value
Description of analysis
All RD50s identified in all strains of mice vs. all human LOAELs identified (Figure 1)	25	198	logRD50 = 1.16(log LOAEL) + 0.77	0.82
Evaluation using male mice and RELs set by OEHHA for airborne toxicants (Figure 2)	16	37	logRD50 = 0.71(log REL) + 2.55	0.71
Evaluation using male mice and the TLV (Figure 3)	24	61	logRD50 = 0.86(log TLV) − 1.13	0.86
Addressing issues of human LOAEL variabilities
Evaluation using all RD50s identified in all strains of mice vs. the lowest human LOAEL for each compound	25	58	logRD50 = 1.13(log LOAEL) + 1.26	0.81
Analysis for male mice log RD50 vs. log LOAEL using lowest RD50 values with the lowest LOAEL values	25	25	logRD50 = 1.01(log LOAEL) + 1.21	0.77
Analysis for male mice log RD50 and human log LOAEL for lower respiratory end points	5	29	logRD50 = 1.06(log LOAEL) + 1.21	0.58
Analysis for male mice log RD50 and human log LOAEL for upper respiratory end points	23	166	logRD50 = 1.22(log LOAEL) + 0.69	0.82
Analysis for male mice log RD50 and human log LOAEL for higher quality human studies	7	43	logRD50 = 1.40(log LOAEL) + 0.98	0.82
Analysis for male mice log RD50 and human log LOAEL for human studies not selected as higher quality	25	155	log RD50 = 1.16(log LOAEL) + 0.73	0.79
Evaluating influence of mouse strain
Evaluation using only Swiss-Webster mice and all human LOAEL values (Figure 2)	19	75	logRD50 = 1.12(log LOAEL) + 0.93	0.74
Evaluation using all non–Swiss-Webster mice and all human LOAEL values (Figure 3)	23	120	logRD50 = 1.20(log LOAEL) + 0.73	0.83
Evaluating changes in exposure duration
Evaluation using male mice and human LOAEL values from exposures of ≤ 10 min	16	67	logRD50 = 1.27(log LOAEL) + 0.726	0.76
Evaluation using male mice and human LOAEL values from exposures of > 10 min	18	127	logRD50 = 1.11(log LOAEL) + 0.838	0.80
Evaluation using male mice and human LOAEL values from exposures of ≥ 60 min	15	101	logRD50 = 1.08(log LOAEL) + 0.89	0.80
Log RD50 vs. log RD50 for RD50 values with time < 10 min	16	44	logRD50 = 1.04(log LOAEL) + 0.76	0.77
Log LOAEL vs. Log RD50 for RD50 values with time > 10 min	10	43	logRD50 = 1.51(log LOAEL) + 0.56	0.87
Log RD50 vs. log LOAEL for RD50 values with time equivalent to 10 min	16	111	logRD50 = 1.3(log LOAEL) + 0.78	0.80
LogRD50 vs. log LOAEL for RD50 values at times not equivalent to 10 min	22	86	logRD50 = 1.09(log LOAEL) + 0.77	0.8

OEHHA, Office of Environmental Health Hazard Assessment.