# Plaaben Compounds--Part I: An Overview of Their Characteristics, Detection, and Impacts
## 5 Paraben Detection
### Detection in Animals
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Parbens(s)** & **Animal** & **Administration Route** & **Results** & **Reference** \\ \hline \hline \multicolumn{4}{c}{Blood and urine analyzed.} \\ \multicolumn{4}{c}{Very low quantity remained in the blood after} \\ \multicolumn{4}{c}{administration, but p-hydroxybenzoic acid was detected} \\ \multicolumn{4}{c}{in blood.} \\ \multicolumn{4}{c}{In 100 mg/kg of MP and PP administered intravenously,} \\ \multicolumn{4}{c}{the ester was only detected in brain, spleen, and pancreas,} \\ \multicolumn{4}{c}{but high concentrations of metabolites were detected in} \\ \multicolumn{4}{c}{ kidneys and liver.} \\ \multicolumn{4}{c}{By oral administration of 1 g/kg/day for 1 year, the} \\ \multicolumn{4}{c}{existence of accumulation of MP or PP was not verified, and} \\ \multicolumn{4}{c}{66\% and 96\% of these doses of MP and PP, respectively,} \\ \multicolumn{4}{c}{} \\ \multicolumn{4}{c}{} \\ \multicolumn{4}{c}{Of the 66\% of MP excreted, 21\% was as p-hydroxybenzoic acid} \\ \multicolumn{4}{c}{acid and 33\% was as glucuronic acid conjugates.} \\ \multicolumn{4}{c}{The recovery of all parabens was between 58\% and 94\%,} \\ \multicolumn{4}{c}{except for BuP which was 40–48\%.} \\ \hline \multicolumn{4}{c}{39\% of MP was excreted as p-hydroxybenzoic acid, 15\% as glycine, 7\% and 15\% as glucuronic acid ester and ether, and} \\ \multicolumn{4}{c}{10\% as sulfuric acid.} \\ \multicolumn{4}{c}{30\% of the dose of propylparaben was excreted as p-hydroxybenzoic acid, 24\% as glycine, 7\% and 13\% as glucuronic acid ester and ether, and 7\% as sulfuric acid.} \\ \multicolumn{4}{c}{MP} \\ \multicolumn{4}{c}{EP} \\ \multicolumn{4}{c}{Rabbits} & Oral (0.4 or 0.8 g/kg) \\ \multicolumn{4}{c}{BuP} \\ \multicolumn{4}{c}{Oral administration of parabens resulted in excretion of} \\ \multicolumn{4}{c}{0.2–0.9\% of the unchanged ester by 24 h.} \\ \multicolumn{4}{c}{As the length of the alkyl chain increased, the rate of} \\ \multicolumn{4}{c}{urinary excretion decreased, so, in general, after 24 h,} \\ \multicolumn{4}{c}{25–39\% was excreted as p-hydroxybenzoic acid, 25–29\% as} \\ \multicolumn{4}{c}{the glycine conjugate, 5–8\% and 10–18\% as ester and ether} \\ \multicolumn{4}{c}{glucuronide, respectively, and 7–12\% as sulfate.} \\ \hline \multicolumn{4}{c}{Quick absorption by gastrointestinal tract and easy} \\ \multicolumn{4}{c}{hydrolyzation into p-hydroxybenzoic acid in} \\ \multicolumn{4}{c}{different organs.} \\ \multicolumn{4}{c}{30 min after administration, paraben metabolites were} \\ \multicolumn{4}{c}{detected in urine, and 90 min after the maximum excretion} \\ \multicolumn{4}{c}{of the metabolites was observed.} \\ \multicolumn{4}{c}{EP} \\ \multicolumn{4}{c}{Rats} & Oral (100 mg) & P-hydroxyhippuric acid was detected in urine after 30 min with an increase in concentration for the next 4 h. \\ \multicolumn{4}{c}{After 90 min, about 67–75\% of the total paraben dose was} \\ \multicolumn{4}{c}{exrected as p-hydroxybenzoic acid, and 8–9\% as glucuronyl} \\ \multicolumn{4}{c}{derivatives.} \\ \multicolumn{4}{c}{The concentration of parabens or benzoic acid in blood was} \\ \multicolumn{4}{c}{extremely low.} \\ \hline \hline \multicolumn{4}{c}{} \\ \multicolumn{4}{c}{EP} \\ \multicolumn{4}{c}{Cats} & Oral (158 mg/kg) & For urine, at 24 and 72 h, about 90\% and 95.6\% of the dose was excreted, respectively, and 6\% and 3\% in feces at 24 h, for EP and PP, respectively. \\ \multicolumn{4}{c}{The two major metabolites were p-hydroxyhippuric acid} \\ \multicolumn{4}{c}{and p-hydroxybenzoic acid.} \\ \multicolumn{4}{c}{After 72 h post oral administration, the PP was} \\ \multicolumn{4}{c}{completely excreted.} \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Detection, metabolization and extraction of parabens in humans. Parabens (MP, EP, PP and BuP) have also been found in fishes in Manila Bay, the Philippines, ranging from 605 to 3450 ng/g lipid weight (gkw) for MP, 46.6 to 195 ng/glw for EP, 46 to 1140 ng/glw for PP and 6.61-37.3 ng/glw for BuP [172].