Assessment of exposure to PCB 153 from breast feeding and normal food intake in individual children using a system approach model

Abstract

Investigators have typically relied on a single or few discrete time points as measures of polychlorinated biphenyl (PCB) body burden, however health effects are more likely to be the result of integrative exposure in time, optionally expressed as an area under the time curve (AUC) of PCB serum concentration. Using data from a subgroup of 93 infants from a birth cohort in eastern Slovakia—a region highly polluted by PCBs—we fit a system type model, customized to our longitudinal measures of serum PCB concentrations in cord, 6, 16, and, 45 month blood specimens. The most abundant congener, PCB 153, was chosen for modeling purposes. In addition to currently used methods of exposure assessment, our approach estimates a concentration time profile for each subject, taking into account mean residence time of PCB 153 molecules in the body, duration of breast feeding, hypothetical PCB 153 concentration in steady-state without breast feeding and alternately without normal food intake. Hypothetical PCB 153 concentration in steady-state without normal food intake correlates with AUC (r=0.84, p<0.001) as well as with duration of breast feeding (r=0.64, p<0.001). It makes possible to determine each subject’s exposure profile expressed as AUC of PCBs serum concentration with a minimum model parameters. PCB body burden in most infants was strongly associated with duration of breast feeding in most, but not all children, was apparent from model output.

The spatial distribution of human exposure to PCBs around a former production site in Slovakia

“…The scope and extent of environmental contamination and the associated impacts on health have been documented in a series of studies (Kočan et al 1994; Kočan et al 2001; Kočan et al 2008; Jusko et al 2014; Langer et al 2014; Hertz-Picciotto et al 2008; Ghosh et al 2013; Patayová et al 2013; Trnovec et al 2013; Verner et al 2013; Jusko et al 2012; Mitra et al 2012; Trnovec et al 2011; Horváthová et al 2011; Dutta et al 2012; Jusko et al 2010; Park et al 2010; Park et al 2007; Park et al 2009; Park et al 2008a; Park et al 2008b; Sonneborn et al 2008a; Trnovec et al 2008; Yu et al 2007; Park et al 2007; Linderholm et al 2007). …”

Prenatal and postnatal exposure to persistent organic pollutants and attention-deficit and hyperactivity disorder: a pooled analysis of seven European birth cohort studies

“…These calculations may have decreased model precision and could lead to exposure misclassification, decreasing our chance of observing an effect. However, breastfeeding is the major source of body burden of PCB, DDE and HCB in young children, 36,38 and we had more accurate information on breastfeeding in some cohorts, where mothers were asked about not only total breastfeeding, but the proportion of breastfeeding during the partial-breastfeeding period. We did a number of sensitivity analyses, amongst others excluding cohorts with fewer than two measurements on children's weight, and the results remained the same, indicating that no major bias has occurred.…”

DPOAEs in infants developmentally exposed to PCBs show two differently time spaced exposure sensitive windows

“…For integrative exposure assessment in time, expressed as an area under the PCB*time curve (AUC), we approximated the PCB 153 serum concentration-time profile for each subject with a mathematical function, taking into account mean residence time of PCB 153 molecules in the body, duration of breast feeding, hypothetical PCB 153 concentration in steady-state without breast feeding and alternately without normal food intake (Trnovec et al, 2011). Such analysis enabled the computation of definite integrals for consecutive time periods.…”