# Plaaben Compounds--Part I: An Overview of Their Characteristics, Detection, and Impacts
## 5 Paraben Detection
### Detection in Humans  
Parabens are also being detected in humans with several and different risks to their lives. In humans, parabens have been detected in urine [150; 151], tumors [28], adipose tissue [152], serum [153], amniotic fluid [6], placental tissues [154; 155], breast milk [155], hair [156] and fingernails [129]. The use of personal care products (pharmaceuticals and cosme) is the main pathway for the exposure to parabens [20; 34], since these types of compounds are present in the composition of daily basis products that can be used for skin, hair, head scalp, lips, mucosae (oral, ocular, and vaginal), avililae and nails [22]. [PERSON] et al. [22] estimated an exposure to propylparaben of 76 mg/day or 1.3 mg/kg/day (1 mg/day for food, 50 mg/day for cosme and personal care products and about 25 mg/day for pharmaceuticals). Additionally, [PERSON] et al. [21] estimated a value of 77.5 mg/day or 1.29 mg/kg/day (considering food at 2.5 mg/day, cosme, and personal care products at about 50 mg/day and drugs at 25 mg/day) for total paraben consumption, what can be transformed into 51.6 mg/day and 0.86 mg/kg/day for just methylparaben [21]. [PERSON] et al. [19] find a consumption of 0.6 (0.01 mg/kg/day) and 0.78 mg/day (0.013 mg/kg/day) for MP and PP, respectively, based on FDA data; these values are higher than the FEMA Possible Average Daily Intake (PADI) for these compounds in food products. For cosme and pharmaceuticals, values of 0.833 and 0.417 mg/kg/day have been estimated, respectively, so the total paraben consumption is predicted to be 75.78 mg/day or 1.26 mg/kg/day [19]. Several laboratory studies have already been carried out to understand the effect of parabens in human organisms, their metabolization and their excretion, as is possible to see in Table 6.  
[PERSON] et al. [56] studied the existence of five parabens at four different locations across the human breast from axilla to sternum, using human breast tissue collected from 40 mastectomies for primary breast cancer. The median values detected were 16.8, 16.6, 5.8, 3.4 and 2.1 ng/g of tissue, for n-PP, MP, n-BuP, EP and iso-BuP, respectively. The PP was detected in higher concentrations in the axilla than the mid breast (or upper outer quadrants) compared to other parabens. [PERSON] et al. [155] detected the presence of parabens in human milk, with mean values of 2.18, 1.26 and 1.42 ng/mL and median values of 1.00, 1.30 and 1.50 ng/mL for MP, EP and n-PP, respectively, and their presence was detected in 15-34% of the defatted milk samples. BuP was not found. [PERSON] et al. [158] detected the presence of parabens in urine of pregnant women and 4-year-old boys from Spain, at median concentrations of 191, 8.8, 29.8 and 2.4 ng/mL for \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Parabens(s)** & **Administration Route** & **Results** & **Reference** \\ \hline \multirow{3}{*}{PP} & \multirow{3}{*}{Oral (2 g)} & 17.4\%, 13.7\%, 3.7\% and 55\% were excreted as p-hydroxybenzoic acid, free glycine and pair glycine and paired with sulfuric acid, respectively. & [22; 35] \\  & & & \\  & & & \\  & & & \\  & & & \\ \hline \multirow{3}{*}{PP} & \multirow{3}{*}{Oral (10 or 20 mg/kg)} & After 60 min, 135 min and 255 min, the paraben was detected in human serum at a maximum of 4.5 \(\mu\)g/mL, but the ester was not detected. & [22; 157] \\  & & & \\ \hline \multirow{3}{*}{MP} & \multirow{3}{*}{It was measured the concentration of paraben esters in human breast tumor.} & \multirow{3}{*}{[28]} \\  & & & \\ \cline{1-1} \cline{4-4}  & & & \\ \cline{1-1} \cline{4-4}  & & & \\ \cline{1-1} \cline{4-4}  & & & \\ \cline{1-1} \cline{4-4}  & & & \\ \cline{1-1} \cline{4-4}  & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Detection, metabolization and extraction of parabens in humans. MP, EP, n-PP and n-BuP, respectively, for pregnant women, and levels of 150, 8.1, 21.5 and 1.2 MP, EP, n-PP and n-BuP, respectively, for the 4-year-old boys. [PERSON] et al.