Meeting Abstract
Chronic exposure to low levels of anthropogenic chemicals in the environment continues to be a major health concern. Due to concerns about the effects on humans and wildlife heavily used persistent organic pollutants (POP’s), such as dichlorodiphenyltrichloroethane (DDT), were banned. However, their ubiquitous nature and persistence allows them to remain within the environment at sub-lethal levels for decades. Although levels of POP’s have been decreasing, they are still high enough to potentially affect physiological functions such as oxidative stress and immunological response parameters. Two species of small mammals (Peromyscus maniculatus and Sigmodon hispidus) were collected at the Redstone Arsenal, a designated EPA SuperFund site in a historically impacted vs. reference site (S. hispidus: n=12 and P. maniculatus n=13 vs 19). Soil samples taken from the DDT abatement site still show levels above the Total Threshold Limit Concentration for DDT (i.e. >1ppm), while other reference areas did not. Preliminary data show significant difference in Body Condition Index (BCI) in both species. Both species had significantly higher BCI in the impacted vs the reference site (P. m.: T28=3.6, p= 0.0009; S. h. T25=2.5, p=0.02). There was also a significant difference in total WBC counts, with both species (S. h.: T25=-2.6; p= 0.01; P. m.: T28=-2.6, p= 0.01) exhibiting lower counts in the impacted vs the non-impacted area. It has been suggested that reduction in WBC’s is due to redistribution from blood to other organs (i.e. skin, mucosal lining, liver) that may enhance immune function during stress. This study can provide critical information on the potential physiological effects of chronic exposure to sub-lethal levels of POPs.
