Later-life effects of early-life benzo(a)pyrene and triphenyl phosphate exposure on respiration in zebrafish (Danio rerio)

Benzo(a)pyrene (BAP) is a polycyclic aromatic hydrocarbon with carcinogenic metabolites. Triphenyl phosphate (TPP) is an organophosphate ester often used as a flame retardant and plasticizer. This study assessed exposures to BAP or TPP early in life to determine effects on respiration later in life in zebrafish (Danio rerio). Whole organismal basal respiration was measured using a swim tunnel. Tissue-specific respiration was then measured for the gonads, liver, heart, and brain of each fish. Fish exposed to BAP exhibited lower total organismal basal respiration compared to controls, while TPP-exposed fish did not have any significant changes. Livers and brains of BAP-exposed fish also had lower mitochondrial respiration, while ovaries were affected in TPP-exposed fish. These findings demonstrate that early-life exposures to BAP and TPP can have profound later-life effects on respiration and mitochondrial function.