Chemical | Current rhinitis(n = 1664),n (% exposed) | No current rhinitis(n = 581),n (% exposed) | OR* (95% CI) | p Trend |
Days/year applied† | ||||
Insecticides | ||||
Carbaryl | ||||
0 | 1547 (88) | 527 (92) | 1.00 | 0.133 |
1–4 | 69 (4) | 19 (3) | 1.09 (0.64 to 1.86) | |
5–9 | 51 (3) | 10 (2) | 1.51 (0.75 to 3.06) | |
10–19 | 32 (2) | 10 (2) | 1.03 (0.49 to 2.17) | |
20 or more | 39 (2) | 8 (1) | 1.74 (0.79 to 3.80) | |
Carbofuran | 0.761 | |||
0 | 1538 (95) | 516 (93) | 1.00 | |
1–4 | 16 (1) | 13 (2) | 0.33 (0.15 to 0.72) | |
5–19 | 36 (2) | 18 (3) | 0.69 (0.38 to 1.24) | |
20 or more | 24 (2) | 6 (1) | 1.50 (0.59 to 3.81) | |
Diazinon | ||||
0 | 1461 (89) | 539 (95) | 1.00 | 0.026 |
1–4 | 76 (5) | 11 (2) | 2.21 (1.15 to 4.27) | |
5–9 | 38 (2) | 8 (1) | 1.16 (0.53 to 2.55) | |
10 or more | 68 (4) | 12 (2) | 1.88 (0.99 to 3.55) | |
Herbicides | ||||
Chlorimuron-ethyl | ||||
0 | 1240 (75) | 449 (79) | 1.00 | 0.335 |
1–4 | 39 (2) | 14 (2) | 0.89 (0.47 to 1.70) | |
5–9 | 62 (4) | 17 (3) | 1.20 (0.68 to 2.12) | |
10–19 | 136 (8) | 38 (7) | 1.45 (0.98 to 2.15) | |
20–39 | 128 (8) | 38 (7) | 1.12 (0.76 to 1.66) | |
40 or more | 45 (3) | 16 (3) | 1.05 (0.58 to 1.92) | |
Dicamba | ||||
0 | 1062 (65) | 395 (71) | 1.00 | 0.189 |
1–4 | 78 (5) | 20 (4) | 1.40 (0.83 to 2.36) | |
5–9 | 103 (6) | 32 (6) | 1.05 (0.68 to 1.61) | |
10–19 | 150 (9) | 43 (8) | 1.14 (0.79 to 1.65) | |
20–39 | 133 (8) | 46 (8) | 1.03 (0.71 to 1.49) | |
40–59 | 51 (3) | 11 (2) | 1.66 (0.84 to 3.27) | |
60 or more | 49 (3) | 12 (2) | 1.36 (0.70 to 2.64) | |
Paraquat | ||||
0 | 1534 (93) | 540 (95) | 1.00 | 0.207 |
1–4 | 36 (2) | 9 (2) | 1.29 (0.60 to 2.77) | |
5–9 | 24 (1) | 6 (1) | 1.37 (0.54 to 3.50) | |
10 or more | 56 (3) | 15 (3) | 1.38 (0.76 to 2.50) | |
Petroleum oil | ||||
0 | 1398 (85) | 518 (91) | 1.00 | 0.029 |
1–9 | 60 (4) | 10 (2) | 1.90 (0.95 to 3.80) | |
10–19 | 60 (4) | 12 (2) | 1.79 (0.94 to 3.43) | |
20–39 | 67 (4) | 10 (2) | 2.31 (1.16 to 4.59) | |
40 or more | 56 (3) | 18 (3) | 1.28 (0.73 to 2.24) | |
2,4-D and glyphosate‡ | ||||
2,4-D only | ||||
0 | 716 (90) | 294 (89) | 1.00 | 0.417 |
1–9 | 38 (5) | 12 (4) | 1.33 (0.67 to 2.67) | |
10–19 | 18 (2) | 9 (3) | 0.67 (0.29 to 1.57) | |
20–59 | 11 (1) | 7 (2) | 0.92 (0.34 to 2.49) | |
60 or more | 11 (1) | 7 (2) | 0.69 (0.25 to 1.89) | |
Glyphosate only | ||||
0 | 716 (78) | 294 (81) | 1.00 | 0.735 |
1–4 | 80 (9) | 26 (7) | 1.27 (0.78 to 2.10) | |
5–9 | 47 (5) | 18 (5) | 0.83 (0.46 to 1.49) | |
10–19 | 41 (5) | 15 (4) | 0.99 (0.53 to 1.86) | |
20–39 | 17 (2) | 7 (2) | 0.97 (0.38 to 2.48) | |
40 or more | 13 (1) | 4 (1) | 1.52 (0.47 to 4.90) | |
Both 2,4-D and glyphosate | ||||
0 | 716 (52) | 294 (62) | 1.00 | 0.009 |
1–19 | 162 (12) | 43 (9) | 1.47 (1.01 to 2.14) | |
20–39 | 161 (12) | 46 (10) | 1.32 (0.92 to 1.91) | |
40–69 | 166 (12) | 47 (10) | 1.42 (0.98 to 2.04) | |
70 or more | 177 (13) | 44 (9) | 1.55 (1.08 to 2.24) |
*Odds ratios were adjusted for age, education status and growing up on a farm.
†Exposure–response categories were collapsed for each pesticide to >1% cases. Numbers do not add up to 2445 due to data missing on covariates.
‡As 2,4-D and glyphosate were strongly correlated, we analysed 2,4-D exposed alone, glyphosate exposed alone, and 2,4-D and glyphosate exposed (cutpoints based on quartiles of the distribution); all three exposure–response models have never users of 2,4-D and glyphosate as the referent group.