Monobenzyl phthalate

Studies on health effects of PAEs in humans have remained controversial due to limitations of the study design. Some findings in human populations are consistent with animal data, suggesting that PAEs and their metabolites produce toxic effects in the reproductive system. Some studies associate monoesters PAEs with semen parameters, sperm DNA damage, and hormones in human population, but none of them are statistically significant. Urinary monomethyl phthalate (MMP), monobenzyl phthalate (MBzP), mono- -butyl phthalate (MBP), MEHP, and monoethyl phthalate (MEP) were associated with poor sperm morphology and vigor, and with low sperm concentration, motility, and linearity [31-35]. However, it is not yet possible to conclude whether phthalate exposure is harmful for human reproduction. 

Limited information was located regarding possible interactions of DEHP with other chemicals in humans. Urinary measurements of the monoester metabolites of seven common phthalates in 289 adults from the U.S. population, determined using the selective and sensitive analytical approach discussed in Section 3.8.1 (Biomarkers Used to Identify or Quantify Exposure to DEHP), showed detectable levels of monoethyl phthalate (95th percentile concentration, 3,750 ppb), monobutyl phthalate (294 ppb), monobenzyl phthalate (137 ppb), 2-ethylhexyl phthalate (21.5 ppb), cyclohexyl phthalate (8.6 ppb), isononyl phthalate (7.3 ppb), and octyl phthalate (2.3 ppb), reflecting exposure to DEHP, dibutyl phthalate, benzyl butyl phthalate, di-(2-ethylhexyl) phthalate, dicyclohexyl phthalate, di-isononyl phthalate, and dioctyl phthalate, respectively (Blount et al. 2000a). Considering evidence such as this which indicates that co-exposure to multiple phthalates can occur, as well as the likelihood that many of these compounds exert effects via a common mechanism of action, there is a potential for interactions between DEHP and other phthalate esters. 

D BP Di-n-butyl phthalate, MnBP Mono-n-hutyl phthalate, BBP Benzyl butyl phthalate, MBnP Monobenzyl phthalate, DEHP Di-(2-ethylhexyl) phthalate, MEHP Mono-2-ethylhexyl phthalate, DnOP Di-n-octyl phthalate, MnOP Mono-n-octyl phthalate, DiNP Di-iso-nonyl phthalate, MiNP Mono-iso-nonyl phthalate, DiDP Di-iso-deeyl phthalate, MiDP Mono-iso-decyl phthalate expressed as the number of carbon atoms in the alkyl side ehain... 

PCBs and phthalates are endocrine-disrupting chemicals that adversely impact male fertility, especially sperm motility. In a sperm motility study, exposure to a mixture of PCB-153 and monobenzyl phthalate or monobutyl phthalate produced greater than expected negative impacts. The authors of the study hypothesized that the mechanism is throngh interactions between PCB metabolites and enzymes responsible for phthalate metabolism [83]. PCBs accumulate in body adipose tissue and metabolize slowly. Phthalates metabolize rapidly and are not known to accumulate in body tissues. Accordingly, it is more than likely that exposures to phthalates long after exposures to PCBs can produce enhanced negative sperm motility effects in men and dramatically reduce their fertility. 

Butylbenzyl phthalate (BBzP) Monobenzyl phthalate (MBzP) 6.50... 

The monoesters, mono butyl, monobenzyl and mono 2-ethylhexyl phthalate have all proved negative [20]. 

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