Relationships between hepatic neoplasms and related lesions and exposure to toxic chemicals in marine fish from the U.S. West Coast.

Abstract

English sole (Parophrys vWtuls) inhabiting pofluted waterways and embayments of Puget Sound, Washington, are af-feted wtha yiofmu}tipl,-ccu ing i tc heptck ,inclun unique dgerative onitions, putaftive-ly preneoplastic foci ofcellular alteration, and neoplasms Results ofa statistical analysis ofthe patterns ofco-occurrence ofthese lesions in wild Engish sole are co stent with the concept that these sins represent morph Ily identifiable steps forming a sequence of progressn ultimately leading to the development of bepatic neoplas This progressive sequence parailels the pattern identified in experimental models of cbemically induced hepatoarcinogenesis in rodents. The rationale for the hypothesis that these lesins in wild Engis sole can be caused by exposure to certain hepatoxic and hepatocarcinogenic xenobiotic compounds in the marine environment is based on the demonstration of ign nt and consistent s l associations between lvels of aromatic hydrocarbons (AHs) in sediment and prvalences of these idiopathic ver lesions; a significant contribution by sediment AHs to the variability in hepatic neoplasm prevalence in a gistic model; ntly increed probabilities for several idiopathic lesions in sole fromcbemicaly contaminated sites in Puget Sound; ignifiant rdations between uptake of polydic aro tic h d as measured by levels offluorescent metabolites of aromatic compounds in bile of sole, and prevalences ofseeral hepatic lesion types; and experimental induction of unique degenerative, prolferative, and putatively preneoplastic focal lesions in English sole inected with elther benzo(a)pyrene or a polycyclic aromatic hydrocarbons (PAH) enriched fraction ofan extract from acontmited urban sediment from Puget Sound. Simlar pes of idiopathic hepatic lesions have been detected in white coaker (Genyonmul nwaus) captured from-onaminatedmine sites in the vicni ofLos Angeks, California. Although the evidence also sggests involement ofxenobiotic contaminants in the etiolo ofhepatic lesons in this species, no strong statistical association between lesion prevalence and contaminant exposure have been estabUshed, primarily due to the low prevalences of these lesions detected in white croaker. Data are not suffkient to conclusively establish the existence ofa human health risk due to consumption of onina-exposed Engish sole and other fish species affected by hepatic neoplasmsor related lesions. Because PAHLs are extensively metabolied in theliver offish, sensitive and reiable methods for detectio ofPAH metabotes in fishtissues need to bedevopedbefore credible esntsofhumanhealth risk due to consumption of PAH-contaminated fish muscle can be conducted.