Pediatric populations may experience substantially higher exposure to both agents and exhibit a higher burden of disease than adults.
Workplace exposures, on the other hand, are typically substantially higher than exposures from other environmental sources.
It should be noted that testicular atrophy and decreased sperm production observed in rats occurs at PE exposure levels substantially higher than human exposure levels in the general environment.
The lower exposure estimates in the HAP studies are substantially higher than counterfactual exposure due to the nearby use of less clean fuels; therefore, these RRs are not directly comparable to those obtained from AAP, SHS, or AS types compared with either the counterfactual (i.e., AAP) or a 0-μg/m exposure (i.e., SHS, AS).
Supported by a previous study, this work suggests that the U.S. population has a substantially higher degree of exposure to TCC compared to Canadian, Greek, and German populations (though the use of disparate methods between the different studies precludes making definitive conclusions on TCC exposure across the globe).
This alternate depiction of the HAP information was necessary because the lowest exposure levels were substantially higher than the counterfactual exposure and, therefore, not directly comparable to the RRs from the other sources.
Further, the risks of anencephalus (adjusted OR 1.96, 95% CI: 0.94, 4.07), and ventricular septal defects (1.81, 95% CI: 0.98, 3.35), and cleft palate (1.56, 95% CI: 1.00, 2.41) were substantially higher in the high exposure category compared with the reference category.
The PCB-exposed workers in our cohort therefore experienced PCB exposures substantially higher than the environmentally exposed individuals in other studies of maternal PCB exposure and secondary sex ratio.
The NOEL suggested from these studies (0.03 mg/m MEHP) is estimated to be substantially higher than normal human exposures (Hansen et al. 2007; Larsen et al. 2004).
