Behavioural effects similar to those seen in monkeys have also been reported for human
infants whose mothers were exposed to PCBs through the intake of contaminated fish
(Michigan study, Jacobson and coworkers; see Section 6.4.3). The effects recorded in
infants were slight, but should still be regarded as adverse. However, the study is not fully
conclusive from an epidemiological point of view. Thus, the causal relationship between
PCB and the effects are not proven due to some potentially important confounding factors
(see Section 6.4.3). On the other hand, a causal relationship is definitely possible.
Furthermore, supportive evidence comes from a similar study performed in North Carolina
(Rogan and coworkers).