Phthalates

Endocrine Disrupting Phthalates

Another group of EDCs are phthalates. These compounds are from a family of industrial compounds, specifically from esters of 1, 2-benzenedicarboxylic acid (Yang et al, 2006). Phthalates are used for numerous different purposes, including industrial solvents and lubricants, as additives in the textile industry and in pesticide formulations. Unfortunately, phthalates are also components in numerous common household consumer products, such as deodorants, perfumes, hair sprays, soap, shampoo and conditioners, therefore allowing individuals to easily come into contact with these compounds (Latini, 2005; Agency for Toxic Substances and Disease Registry, 1995). In addition, individuals purchasing cosmetics and personal care products are unaware of the presence of phthalates because their presence is often not noted on labels (Barrett, 2005). Moreover, phthalates pose numerous harms to the environment and to humans and are therefore referred to as ubiquitous environmental contaminants (Angerer et al, 2003) because they can be found almost anywhere.

Environmental contaminants and dermal contact and inhalation

These ubiquitous environmental contaminants have the capability to transfer from packaging products to foods and to the environment (Garbowska et al, 2006). The primary route of phthalate exposure to the population is through ingestion and oral exposures. The exposure route also depends on the molecular weight of the specific phthalate. For example, low molecular weight phthalates have the ability to be more easily absorbed, such as through the skin, in addition to being more volatile and evaporative, thereby being easily inhaled (Kohn et al, 2000). Therefore, the major routes of exposure of phthalates are through dermal contact and inhalation (Yang et al, 2006).

Physical properties and applications of phthalates

Furthermore, through considering the length and branching of the dialkyl or alkryl-aryl side chains of its structure, the type of physical properties and applications of phthalates can be determined. For instance, di-[2-ethylhexyl] phthalate (DEHP), diethylphthalate (DEP), di-iso and di-n-butylphthalate (DiBP, DnBP), butylbenzyl-phthalate (BBzP), di-iso-nonylphthalate (DiNP) and di-n-octylphthalate (DnOP) (Angerer et al, 2003; ASTDR, 1995; Yang et al, 2006) are different phthalates because the length and branching of their side chains differ from each other. Moreover, these compound properties dictate not only the effects the compound will have on an individual, but also the amount of exposure one will have to the compound. For example, DiNP and DIDP have a lower exposure impact to populations because their production volumes are lower, as their uses are more limited in comparison to other phthalates. Unfortunately, in the future it is predicted that DiNPs and DIDPs will have a larger impact because these compounds are currently being used as replacements for DEHP (Latini, 2005). The impact that the compound DEHP has on the environment was found through investigating the synthesis and analysis of the metabolism of this compound to the secondary metabolites mono-[2-ethyl-5-hydroxyl]-phthalate, mono-[2-ethyl-5-oxyhexyl]-phthalate, and mono-[2-ethylhexyl]-phthalate in the urine. From this investigation and analysis, it helped to provide an estimation of the amount of exposure a population has to DEHP (Angerer et al, 2004).

Highest DEHP concentration

The highest DEHP concentration in the environment is found in food, with lower levels found in indoor air and drinking water (Yang et al, 2006). In addition, when the daily DEHP intake concentrations in formula-fed infants, breast-fed infants, toddlers, children, teenagers and adults were observed, it was found that the exposure in children was twice as high in comparison to adults. This is partly because of the differences in body weight between children and adults and fat composition, as children have a higher fat composition.

References:

Yang M, Park MS, and Lee HS. 2006. Endocrine Disrupting Chemicals: Human Exposure and Health Risks. J. Environmental Science and Health Part C. 24: 183-224.

Latini G. 2004. Monitoring phthalate exposure in humans. Clinica Chimica Acta. 361:20-29.

Agency for Toxic Substances and Disease Registry (ATDSR). 2000. Toxicological profile for di(2-ethylhexyl)phthalate (DEHP). Atlanta, GA: ATDSR.

Barrett J. 2005. Chemical Exposures: The Ugly Side of Beauty Products. Environmental Health Perspectives. 113(1):A24.

Angerer J., Drexler H., and Koch HM. 2003. An estimation of the daily intake of di(2-ethylhexyl)phthalate (DEHP) and other phthalates in the general population. Int J Hyg Environ Health. 206:77-83.

Garbowska K, Isidorov VA, Kotowska U. 2006. Distribution coefficients of phthalates between absorption fiber and water and its using in quantitative analysis. Analytica Chimica Acta. 560:110-117.

Kohn MC., Masten SA., Parham F., Portier CJ., and Shelby MD. 2000. Human exposure estimates for phthalate. Environ Health Perspect. 108(10):A440-443.