Ingestion of environmentally contaminated Lake Ontario salmon by laboratory rats increases avoidance of unpredictable aversive nonreward and mild electric shock.

Abstract

To determine what behavioral changes are caused by consumption of Lake Ontario salmon, a 30% diet of Lake Ontario or control Pacific Ocean salmon was fed to rats for 20 days. In Experiments 1 and 2 (preference-for-predictability E-maze test), rats fed Lake Ontario salmon developed a preference for predictable food rewards more quickly than did the control rats. In Experiments 3 (passive avoidance) and 4 (conditioned suppression), rats fed Lake Ontario salmon suppressed responding to food far more after the introduction of mild electric shocks than did control rats. All results supported the hypothesis that ingestion of Lake Ontario salmon, contaminated with polychlorinated biphenyls, mercury, lead, etc., increases the reactivity of rats to aversive events. The results were successfully simulated by DMOD, a mathematical model of learning, using the assumption that rats fed Lake Ontario salmon find unpredictable nonreward and mild shock more aversive.

Prenatal PCB exposure, the corpus callosum, and response inhibition.

“…Immediately after the CPT, each child was asked to report how he or she felt about performing the task. This was in response to Daly's findings (Daly 1992;Daly et al 1989) that rats fed Lake Ontario fish were more reactive to negative events. The child was verbally asked the question "How much fun did you have doing this activity?"…”

Developmental effects of endocrine-disrupting chemicals in wildlife and humans.

“…Although this procedure cannot rule out chemicals devoid of hormonal activity that may disrupt development through other mechanisms, it can at least rule out compounds like DDT, chlordecone, alkylphenols, and some PCBs, which are estrogen agonists. It is also essential to continue to examine transgenerational effects in animal studies because some pollutants require metabolism in vivo to exert hormonal effects and because neurobehavioral and other developmental effects cannot be addressed with in vitro models (96,97 …”

In Vivo and in Vitro Exposure to PCB 153 Reduces Long-Term Potentiation

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