Specific localization of polychlorinated biphenyls in clams (Mya arenaria) from environmentally impacted sites

Hemocytic neoplasia (HN) develops in soft shell clams (Mya arenaria L.) in coastal locations throughout the world. However, the prevalence of this neoplasm is higher than background levels when clams are collected from a polychlorinated biphenyl (PCB)-contaminated site, New Bedford Harbor (NBH), MA. Immunohistochemistry was used to examine the relationship between the accumulation of PCBs in tissue by M. arenaria and the development of neoplasia in the hemolymph. PCBs preferentially localized in normal and neoplastic hemocytes, in the ovary and in several other tissues. The specific reactivity of tissues with PCB antibodies corresponded to a high reported prevalence (60%) of neoplasia. Understanding the biological implication of PCB accumulation in environmentally impacted animals, particularly in reproductive tissue, is relevant to all species.