Table 1.
Environmental risk factors for childhood leukemia
| Childhood Leukemia Risk Factor | Exposure Measure | Level of Consensus | Subtype Specificity | Exposure Details | Odds Ratio (95% CI) |
|---|---|---|---|---|---|
|
| |||||
| Home pesticide use | Parental interview | Pooled analysis of 12 studies from CLIC29 | ALL | Before conception | 1.39 (1.25, 1.55) |
| ALL | During pregnancy | 1.43 (1.32, 1.54) | |||
| ALL | After birth | 1.36 (1.23, 1.51) | |||
| AML | Before conception | 1.49 (1.02, 2.16) | |||
| AML | During pregnancy | 1.55 (1.21, 1.99) | |||
| AML | After birth | 1.08 (0.76, 1.53) | |||
|
| |||||
| Parental occupational exposure to pesticides | Parental interview | Pooled analysis of 13 studies from CLIC & meta-analysis of CLIC + non-CLIC studies74 | ALL | Maternal during pregnancy | 1.01 (0.78, 1.30) |
| ALL | Paternal at conception | 1.20 (1.06, 1.38) | |||
| T-cell ALL | Paternal at conception | 1.42 (1.04, 1.94) | |||
| ALL after 5y | Paternal at conception | 1.38 (1.13, 1.67) | |||
| AML | Maternal during pregnancy | 1.94 (1.19, 3.18) | |||
| AML | Paternal at conception | 0.91 (0.66, 1.24) | |||
|
| |||||
| Proximity to agricultural pesticide application | GIS Model | Novel finding55 | ALL | Insecticides, moderate, lifetime | 1.5 (0.9, 2.4) |
| ALL | Fumigants, moderate, lifetime | 1.7 (1.0, 3.1) | |||
| ALL | Organophosphates, moderate, lifetime | 1.6 (1.0, 2.7) | |||
| ALL | Chlorinated phenols, moderate, lifetime | 2.0 (1.0, 3.8) | |||
| ALL | Triazines, moderate, lifetime | 1.9 (1.0, 3.7) | |||
|
| |||||
| Chlorthal, an herbicide | Settled dust levels | Novel finding80 | ALL | Detected, 1st Tertile vs. Not Detected | 1.49 (0.82, 2.72) |
| ALL | Detected, 2nd Tertile vs. Not Detected | 1.49 (0.83, 2.67) | |||
| ALL | Detected, 3rd Tertile vs. Not Detected | 1.57 (0.90, 2.73) | |||
|
| |||||
| Parental smoking | Parental interview | Pooled analysis of 14 studies from CLIC & meta-analysis of CLIC + non-CLIC studies83 | AML | Paternal at any time | 1.34 (1.11, 1.62) |
| AML | Maternal during pregnancy, Latinas | 2.08 (1.20, 3.61) | |||
| AMMoL | Paternal at any time | 1.87 (1.08, 3.25) | |||
|
| |||||
| Home paint use | Parental interview | Pooled analysis of 8 studies from CLIC86 | ALL | 1–3 months before conception | 1.54 (1.28, 1.85) |
| ALL | During pregnancy | 1.14 (1.04, 1.25) | |||
| ALL | After birth | 1.22 (1.07, 1.39) | |||
| ALL | Professional painter, during pregnancy | 1.66 (1.21, 2.28) | |||
| ALL - t(12;21) | During pregnancy | 1.51 (1.08, 2.11) | |||
|
| |||||
| Parental occupational exposure to paint | Parental interview | Pooled analysis of 13 studies from CLIC89 | ALL | Paternal at conception | 0.93 (0.76, 1.14) |
| ALL | Maternal during pregnancy | 0.81 (0.39, 1.68) | |||
| AML | Paternal at conception | 0.96 (0.65, 1.41) | |||
| AML | Maternal during pregnancy | 1.31 (0.38, 4.47) | |||
|
| |||||
| Meta- analysis88 | ALL | Maternal during pregnancy | 1.23 (1.02, 1.47) | ||
|
| |||||
| Parental occupational exposure to solvents | Parental interview | Meta- analysis88,90 | ALL | All solvents, maternal during pregnancy | 1.25 (1.09, 1.45) |
| ALL | Petroleum, maternal during pregnancy | 1.42 (1.10, 1.84) | |||
| ALL | Benzene, maternal during pregnancy | 1.71 (0.91, 3.24)* | |||
|
| |||||
| Replicated91 | ALL | Org. solvents, paternal at conception | 1.48 (1.01, 2.16) | ||
| ALL | Cl-hydrocarbon, paternal at conception | 2.28 (0.97, 5.37) | |||
|
| |||||
| Traffic- related air pollution | GIS model | Two independent meta- analyses92,93 | ALL | Traffic density | 1.25 (0.92, 1.69) |
| Any | Traffic density | 1.53 (1.12, 2.10) | |||
| ALL | Nitrogen dioxide estimates | 1.21 (1.04, 1.41) | |||
| AML | Benzene estimates | 2.28 (1.09, 4.75) | |||
|
| |||||
| PAHs | Settled dust levels, vacuum cleaners | Novel finding94 | ALL | Benzo[a]pyrene | 1.42 (0.95, 2.12) |
| ALL | Dibenzo[a,h]anthracene | 1.98 (1.11, 3.55) | |||
| ALL | Benzo[k]fluoranthene | 1.71 (0.91, 3.22) | |||
| ALL | Indeno[1,2,3-c,d]pyrene | 1.81 (1.04, 3.16) | |||
| ALL | PAH toxic equivalence | 2.35 (1.18, 4.69) | |||
|
| |||||
| PCBs | Settled dust levels | Novel finding81 | ALL | Any PCB detected vs. none detected | 1.97 (1.22, 3.17) |
| ALL | Top quartile Σ6PCB vs. bottom quartile | 2.78 (1.41, 5.48) | |||
|
| |||||
| PBDEs | Settled dust levels | Novel finding95 | ALL | Top quartile ΣPenta-BDEs vs. bottom | 0.7 (0.4, 1.3) |
| ALL | Top quartile ΣOcta-BDEs vs. bottom | 1.3 (0.7, 2.3) | |||
| ALL | Top quartile ΣDeca-BDEs vs. bottom | 1.0 (0.6, 1.8) | |||
| ALL | BDE-196 concentrations | 2.1 (1.1, 3.8) | |||
| ALL | BDE-203 concentrations | 2.0 (1.1, 3.6) | |||
| ALL | BDE-206 concentrations | 2.1 (1.1, 3.9) | |||
| ALL | BDE-207 concentrations | 2.0 (1.03, 3.8) | |||
ALL=acute lymphoblastic leukemia; AML=acute myeloblastic leukemia; AMMoL=acute myelomonocytic leukemia; CI=Confidence Interval; CLIC=Childhood Leukemia International Consortium; GIS=Geographic Information Systems
ALL=acute lymphoblastic leukemia; AML=acute myeloblastic leukemia; CI=Confidence Interval; CLIC=Childhood Leukemia International Consortium; GIS=Geographic Information Systems; PAHs=polycyclic aromatic hydrocarbons; PCBs=polychlorinated biphenyls; PBDEs=polybrominated diphenyl ethers
*
Indicates relative risk reported