EWG || Human Toxome Project
chemical information
CAS RN:

00085-68-7

Chemical Class:

Phthalates

Found in these people:

Lucy Waletsky

Found in these locations:

Pleasantville, NY


Summary

Found within many consumer products, phthalates are industrial plasticizers that impart flexibility and resilience to plastic, among other uses. Butyl benzyl phthalate (BBzP) is used in vinyl flooring, adhesives, sealants, stains, texture coatings, car-care products, and to a lesser extent, some personal care products (EWG 2003; Wolff 2007; CDC 2005). Exposure to BBzP occurs through direct use of products containing this chemical, as well as through inhalation of contaminated air (CDC 2005). In the body, BBzP is converted primarily to the metabolite, or breakdown product, monobenzyl phthalate (mBzP), and in smaller amounts to mono-n-butyl phthalate (mBuP) (CDC 2005).

In September 2000, scientists from the Centers for Disease Control and Prevention (CDC) conducted the first accurate measurements of human phthalate exposures, and reported finding phthalates in every one of 289 people tested, at surprisingly high levels (Blount 2000). The latest exposure study from CDC indicates that mBzP is a widespread contaminant of the human body (CDC 2005). Measurements of mBzP in the urine of over 2,500 Americans indicate that women are more exposed than men, and younger children (ages 6-11) are more exposed than older children (ages 12-19), who are in turn more exposed than adults (CDC 2005). In a recent study of girls age 6 to 8 spearheaded by Mount Sinai School of Medicine, this particular phthalate metabolite was found in 89 of 90 girls tested (Wolff 2007). The European Union has banned use of some phthalates in cosmetics and other consumer products, in response to concerns about exposure as well as toxicity.

Phthalates are potent toxins to the male reproductive system. High levels of mBzP are associated with reduced levels of sperm motility and concentration, and alterations in hormone levels in adult men (Duty 2003, 2004, 2005). A recent study of 134 births found marked differences in the reproductive systems of baby boys whose mothers had the highest mBzP phthalate measurements during pregnancy (Swan 2005). A second study indicates that these mothers' exposures were not extreme, but rather were typical for about one-quarter of all U.S. women (Marsee 2006). Further research documented decreased testosterone levels among baby boys exposed to phthalates in their mother's breast milk (Main 2006).

In addition to this epidemiological research on humans, laboratory studies indicate phthalates cause a broad range of birth defects and lifelong reproductive impairments in animals exposed in utero and shortly after birth (Marsman 1995; Wine 1997; Ema 1998; Mylchreest 1998, 1999 2000; Gray 1999). Phthalate exposures damage the testes, prostate gland, epididymis, penis, and seminal vesicles in laboratory animals (e.g., Mylchreest 1998); most of these effects persist throughout the animal's life. BBzP in particular causes significant reproductive toxicity including decreased sperm production, altered sexual development in neonates, delayed sexual maturation in females, altered levels of certain reproductive hormones such as testosterone, and toxicity to the testes, prostate, and seminal vesicle.

Other effects include decreased thyroid hormone (triiodothyronine), pancreatic lesions, cellular changes in the thymus and bone marrow, liver toxicity, kidney effects, skin lesions and altered levels of red blood cells. Developmental effects include fetal death, decreased birth weight and fetal malformation (especially of urinary tract, eyes and spine). Mono-n-butyl phthalate (MBuP), a minor metabolite of BBzP, causes undescended testes, testicular lesions, feminization of the male fetus, extra nipples in male rats, deformed vertebrae, and cleft palate (CERHR 2000a). In addition, EPA considers BBzP to be a possible human carcinogen.

Further epidemiological studies indicate phthalates may produce non-reproductive health effects in people. Increased levels of mBzP, the primary breakdown product of BBzP, were associated with increased waist circumference and insulin resistance in adult men in the United States (Stahlhut 2007). According to the American Heart Association (2007), over 60 million Americans have insulin resistance; 1 in 4 of these people develop Type 2 diabetes. In another study of 400 children, half with allergies, high levels of BBzP in dust were associated with rhinitis and eczema (Bornehag 2004).




Butyl benzyl phthalate

Used in plastics like PVC, adhesives, coatings. Animal studies indicate toxicity to male reproductive system, hormone activity.

Butyl benzyl phthalate has been found in 1 of the 9 people tested in EWG/Commonweal studies.


Other health concerns for Butyl benzyl phthalate (References)

health concern or target organ weight of evidence
Immune system (including sensitization and allergies)limited
Chronic effects, generalunknown
Respiratory systemunknown


Results for Butyl benzyl phthalate

in blood serum (lipid weight)

Showing results from EWG/Commonweal Study #1, industrial chemicals and pesticides in adults

EWG/Commonweal results

  • found in 1 of 9 people in the group

found in 1 of 9 people, but not quantified


Detailed toxicity classifications (References)

classification governing entity/references
Limited evidence in humans - immune system toxicityBornehag C, Sundell J, Weschler CJ. The association between asthma and allergic symptoms in children and phthalates in house dust: a nested case-control study. Environmental Health Perspectives 112: 1393-1397 (2004).
Chronic effects, general - weight of evidence unknown/unassessedStahlhut RW, van Wijngaarden E, Dye TD, Cook S, Swan SH. 2007. Concentrations of urinary phthalate metabolites are associated with increased waist circumference and insulin resistance in adult U.S. males. Environmental health perspectives 115(6): 876-882.
Limited evidence in humans - immune system toxicityBornehag C, Sundell J, Weschler CJ. The association between asthma and allergic symptoms in children and phthalates in house dust: a nested case-control study. Environmental Health Perspectives 112: 1393-1397 (2004).
Respiratory system toxicity - weight of evidence unknown/unassessedBornehag C, Sundell J, Weschler CJ. The association between asthma and allergic symptoms in children and phthalates in house dust: a nested case-control study. Environmental Health Perspectives 112: 1393-1397 (2004).
Respiratory system toxicity - weight of evidence unknown/unassessedBornehag C, Sundell J, Weschler CJ. The association between asthma and allergic symptoms in children and phthalates in house dust: a nested case-control study. Environmental Health Perspectives 112: 1393-1397 (2004).