Table 1.
Selected external exposures categorized according to level of biological plausibility, known or surmised pathways of exposure, capacity to affect large populations, feasibility of conducting external measurements on large populations, and capacity to measure/infer individual-level exposure or dose
| Exposure | 1. Biological plausibility | 2. Known or surmised pathways of exposure | 3. Capacity to affect large populations | 4. Feasibility of conducting external measurements on large populations | 5. Capacity to measure/infer individual-level exposure or dose |
|---|---|---|---|---|---|
| ENVIRONMENTAL | |||||
| Air | |||||
| Outdoor air pollution (human origin) | H | H (I) | H | L | M |
| Indoor air pollution (human origin) | H | H (I) | H | L | M |
| Pollen/mold/fungus (natural origin with human influence) | H | H (I, In, D, Mu) | H | L | L |
| Dust (phthalates/metals/pesticide residues) | H | H (I, In, D, Mu) | H | L | M |
| Noise | H | H (P) | H | M | M |
| Radiation | |||||
| Radon | H | H (I) | H | L | M |
| Ultraviolet radiation | H | H (P) | H | L | M |
| Electromagnetic fields | M | H (P) | H | M | M |
| Water | |||||
| Surface water contamination (infectious agents/chemicals) | H | H (In, D, Mu) | H | L | M |
| Groundwater contamination (infectious agents/chemicals) | H | H (In) | H | M | M |
| Drinking water (chlorination by-products) | H | H (I, In) | H | L | M |
| Weather | |||||
| Heat/humidity | H | H (P) | H | H | H/M |
| Extreme events (e.g., lightning-induced asthma from pollen release) | M | H (Mu) | M | M | M |
| Consumer products | |||||
| Flame retardants (PBDEs) | M | M | H | L | L |
| Fragrance products (musk, musk ketone) | M | L | M | L | L |
| Nicotine products | M | H | L | M | M |
| Flea products (fipronil) | M | M | L | L | L |
| Built environment | |||||
| Ambient light | M | M (P) | H | L | M |
| Green/blue space | M | H (Mu) | H | M | M |
| Point, line, and area sources that emit numerous exposures (e.g., oil refineries, roadways, ports, goods movement, emergencies) | H | M | H | H | L, depending on specific exposure |
| Other | |||||
| Soil contamination | H | H (In, In, D, Mu) | H | L | M |
| OCCUPATIONAL | |||||
| Volatile organic compounds (benzene, naphthalene) | L–H, depending on specific occupation | H (Mu) | L–H, depending on prevalence | M | M |
| Phthalates (diethyl phthalate-fragrance vehicle, butyl benzyl phthalate-plasticizer for floor tile, carpet backing) | L–H, depending on specific occupation | H (Mu) | L–H, depending on prevalence | L | L |
| Polycyclic aromatic hydrocarbons (retene, phenanthracne, dibenzo[a]pyrene) | L–H, depending on specific occupation | H (Mu) | L–H, depending on prevalence | M | L |
| LIFESTYLE | |||||
| Smoking | H | H (I) | M–H, depending on prevalence | M | L |
| Physical activity | H | H (P) | H | M | M |
| Diet | H | H (In, D) | H | L | L |
| Drug abuse | H | H (In, P) | H | L | L |
| Alcohol abuse | H | H (In) | H | M | L |
| SOCIAL | |||||
| Violence, crime, social disorder, inequality, racism, discrimination, hate crimes, etc. | L–H, depending on specific stressor | M (P) | H | L | L–M |
| Stress | M | M (P) | H | L | M |
| INFECTIOUS AGENTS/VECTORS | |||||
| Birds, pigs, rats, bats, other species capable of causing health effects or increasing susceptibility | L–H, depending on specific stressor | M (P, In, I, Mu) | L–H, depending on prevalence | L | L–M |
Abbreviations: D, dermal absorption; H, high; I, inhalation, In, ingestion; L, low; M, medium; Mu, multiple (i.e., more than two); O, other; P, physical; PDBE, polybrominated diphenyl ether.