Table 4.
Proportional change in pesticide concentration (eβ) and variance components from mixed-effects models and percent of variability explained by the explanatory variables (fixed effects)
| Pesticide/ Explanatory variable | Regression coefficients from mixed-effects models (95% CI) | Variance components from null models | Variance components from mixed-effects models | ||
|---|---|---|---|---|---|
| σ2BW | σ2WI | σ2BW (% exp)a | σ2WI (% exp)b | ||
| Carbamates | |||||
| Carbaryl | 1.10 | 1.35 | 0.62 (44) | 0.99 (27) | |
| Ants/flies/roachesc | 2.25 (1.21, 4.22) | ||||
| Professional outdoor onlyc | 1.21 (0.55, 2.67) | ||||
| Professional outdoor and indoorc | 0.41 (0.15, 1.13) | ||||
| Months after first visit | 0.96 (0.93, 0.98) | ||||
| Remove shoesd | 0.24 (0.08, 0.74) | ||||
| Propoxur | 2.02 | 0.75 | 2.14 (–6) | 0.58 (23) | |
| Months after first visit | 0.96 (0.94, 0.98) | ||||
| Organochlorines | |||||
| Chlordane | 3.15 | 0.16 | 2.66 (16) | 0.14 (13) | |
| Home built 1990 or latere | 0.13 (0.02, 0.89) | ||||
| Home built 1970–1989e | 0.70 (–0.98, 2.37) | ||||
| Months after first visit | 0.99 (0.97, 1.0) | ||||
| Methoxychlor | 1.76 | 1.51 | 2.38 (–35) | 1.25 (17) | |
| Professional outdoor onlyc | 1.56 (0.52, 4.65) | ||||
| Professional outdoor and indoorc | 0.22 (0.05, 0.94) | ||||
| Organophosphates | |||||
| Chlorpyrifos | 0.40 | 0.43 | 0.32 (20) | 0.39 (9) | |
| Bees/wasps/hornetsc | 1.86 (1.15, 3.01) | ||||
| Dog onlyf | 2.36 (0.99, 5.61) | ||||
| Both cat and dogf | 1.79 (0.75, 4.25) | ||||
| Diazinon | 2.97 | 0.99 | 2.78 (6) | 0.65 (34) | |
| Lawn/gardenc | 1.73 (1.01, 2.95) | ||||
| Professional outdoor onlyc | 2.97 (1.30, 6.79) | ||||
| Professional outdoor and indoorc | 0.70 (0.20, 2.49) | ||||
| Months after first visit | 0.96 (0.93, 0.98) | ||||
| Pyrethroids | |||||
| Cyfluthrin | 1.55 | 0.84 | 1.08 (30) | 0.71 (15) | |
| Professional outdoor onlyc | 4.71 (2.03, 10.9) | ||||
| Professional outdoor and indoorc | 1.07 (0.29, 3.02) | ||||
| Home built 1990 or latere | 4.20 (1.06, 16.7) | ||||
| Home built 1970–1989e | 0.54 (0.14, 2.06) | ||||
| Cypermethrin | 3.58 | 0.74 | 3.34 (7) | 0.60 (19) | |
| Professional outdoor onlyc | 3.31 (1.45, 7.53) | ||||
| Professional outdoor and indoorc | 1.40 (0.52, 3.76) | ||||
| Other indoor pestc | 1.42 (0.35, 1.40) | ||||
| Months after first visit | 0.98 (0.95, 1.00) | ||||
| Permethrin | 2.40 | 0.37 | 2.36 (2) | 0.28 (24) | |
| Professional outdoor onlyc | 3.49 (1.75, 6.94) | ||||
| Professional outdoor and indoorc | 1.29 (0.73, 2.26) | ||||
| Carpet age 4–10 yearsg | 3.49 (1.75, 6.94) | ||||
| Carpet age > 10 yearsg | 3.49 (1.75, 6.94) | ||||
| Synergist | |||||
| Piperonyl butoxide | 6.23 | 0.99 | 7.57 (–21) | 0.58 (39) | |
| Ants/flies/roachesc | 0.39 (0.22, 0.69) | ||||
| Lawn/gardenc | 1.75 (1.03, 2.96) | ||||
| Professional lawnc | 0.31 (0.08, 1.13) | ||||
| Herbicides | |||||
| Dacthal | 2.20 | 0.96 | 1.56 (29) | 0.94 (2) | |
| Fleas/ticksc | 0.50 (0.23, 1.08) | ||||
| Dog onlyf | 7.63 (1.33, 43.8) | ||||
| Both cat and dogf | 0.28 (–1.42, 1.99) | ||||
| Simazine | 1.30 | 2.20 | 1.31 (–1) | 1.88 (15) | |
| Ants/flies/roachesc | 0.28 (0.12, 0.65) | ||||
| Trifluralin | 1.54 | 0.32 | 1.06 (31) | 0.32 (0) | |
| CPUR metrich | 1.04 (1.01, 1.08) | ||||
| Abbreviations: σ2BW, between-home variance; σ2W, within-home variance; CI, confidence interval; % exp, percent explained. a[(σ2BWnull–σ2BWmixed-effects)/σ2BWnull] x 100. b[(σ2WInull–σ2WImixed-effects)/σ2WInull] x 100. cReference: no reported treatments of each particular kind of treatment. dReference: did not typically remove shoes before entry. eReference: homes built before 1970. fReference: owned no cat or dog. gReference: carpet < 4 years old. hDensity of agricultural/public land application within a 1,250 m buffer zone around residence. | |||||