Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/24/2017
Publication Date: N/A
Interpretive Summary: .
Technical Abstract: Twenty-seven environmental contaminants and pharmaceuticals encompassing a wide range of physicochemical properties were utilized to determine the effects of milk processing on xenobiotic distribution among milk fractions. Target compounds included radiolabeled antibiotics [ciprofloxacin (CIPR), clarithromycin (CLA), erythromycin (ERY), oxytetracycline (OTET), penicillin G (PENG), sulfadimethoxine (SDMX), and thiamphenicol (TAP)], anthelmintics [ivermectin (IVR), praziquantal (PZQ), and thiabendazole (THIA)], analgesics and antipyretics [acetaminophen (TYL), aspirin (ASP), flunixin (FNX), ketoprofen (KETO) and phenylbutazone (PBZ)], a hormone (estrone, E1), and environmental contaminants and/or metabolites [brominated diphenyl ether-99 (BDE-99), bisphenol A (BPA), glyphosate (GLY), ß-hexabromocyclododecane (ß-HBCD), imidacloprid (IMI), polychlorinated biphenyl-118 (PCB-118), tetrabromobisphenol A (TBBPA), methylsulfone PCB-101 (MeSO2 PCB), triclocarban (TCC), 1278-tetrachloro dibenzo-p-dioxin (1278-TCDD), and 1378-hydroxy TCDD (OH-TCDD)]. Radioactive distribution into skim milk, milk fat, curd, whey, and the permeate or retentate from whey passed through 10 kDa filters was quantified for each chemical. Greater than 75% of radioactivity was distributed into milk fat for ß-HBCD, BDE-99, IVR, MeSO2 PCB, PCB118, TCC, and TCDD. About 50% of the phenolic chemicals such as BPA, OH-TCDD and TBBPA were distributed into milk fat. In contrast, polar compounds including ASP, CIPR, CLA, ERY, GLY, IMI, KETO, OTET, PENG, PZQ, SDMX, TAP, THIA, and TYL were poorly (<5%) distributed into milk fat. Log D values were better indictors than log P values for predicting the distribution of chemicals between fat and skim fractions, but was less effective at predicting distributions between insoluble (curd) and soluble (whey) proteins. When whey was separated into retentate and permeate (~1:2 v/v), > 85% of IVR, PCB-118 and TCC remained in retentate indicating these chemicals had high affinity for whey proteins. Compounds associated with < 10 % whey protein included ASP, GLY, IMI, OTET, PENG, TAP, and TYL. These data may be beneficial for predicting the distribution of xenobiotics into dairy products during milk contamination events.