The relationship between environmental exposures to phthalates and DNA damage in human sperm using the neutral comet assay.

Abstract

Phthalates are industrial chemicals widely used in many commercial applications. The general population is exposed to phthalates through consumer products as well as through diet and medical treatments. To determine whether environmental levels of phthalates are associated with altered DNA integrity in human sperm, we selected a population without identified sources of exposure to phthalates. One hundred sixty-eight subjects recruited from the Massachusetts General Hospital Andrology Laboratory provided a semen and a urine sample. Eight phthalate metabolites were measured in urine by using high-performance liquid chromatography and tandem mass spectrometry; data were corrected for urine dilution by adjusting for specific gravity. The neutral single-cell microgel electrophoresis assay (comet assay) was used to measure DNA integrity in sperm. VisComet image analysis software was used to measure comet extent, a measure of total comet length (micrometers); percent DNA in tail (tail%), a measure of the proportion of total DNA present in the comet tail; and tail distributed moment (TDM), an integrated measure of length and intensity (micrometers). For an interquartile range increase in specific gravity-adjusted monoethyl phthalate (MEP) level, the comet extent increased significantly by 3.6 micro m [95% confidence interval (95% CI), 0.74-6.47]; the TDM also increased 1.2 micro m (95% CI, -0.05 to 2.38) but was of borderline significance. Monobutyl, monobenzyl, monomethyl, and mono-2-ethylhexyl phthalates were not significantly associated with comet assay parameters. In conclusion, this study represents the first human data to demonstrate that urinary MEP, at environmental levels, is associated with increased DNA damage in sperm.

Molecular requirements for doxorubicin-mediated death in murine oocytes

“…3,10,[20][21][22] We focused on describing characteristics of apoptosis: mainly morphological changes (e.g., condensation, budding and cellular fragmentation) and biochemical alterations (i.e., DNA cleavage using Comet Assay Kit, Trevigen, Gaithersburg, MD, USA). Analysis of the comets to generate quantitative data was performed using a computer-based program (Duty et al 36 VisComet; Impuls Computergestutzte Bildanalyse GmbH, Gilching, Germany). The percentage of oocytes that underwent apoptosis out of the total number of oocytes cultured per drop in each experiment was then calculated.…”

Exposure assessment of phthalate esters in Japanese pregnant women by using urinary metabolite analysis

“…Although single spot urine sample was usually used for exposure assessment [7,[13][14][15][16][17], concern has been raised over whether monoester concentration in single spot urine represents the subject's long-term exposure to phthalate esters because biological half-life in human body is short. Hoppin et al [18], Hauser et al [19], and Teitelbaum et al [20] reported utility of single spot urine for phthalate esters exposure assessment; however, Fromme et al [21] did not.…”

Plasticizer concentration in cord blood cryopreserved with DMSO

“…Sperm DNA damage was measured using neutral comet assay. In an analysis of 168 males (Duty et al 2003b), there was an exposure-response relation between MBP levels and sperm motility and concentration. Monobutyl benzyl phthalate (MBBP) levels were inversely associated with sperm concentration.…”

“…In the regression analysis fT decreased significantly with increasing total phthalate ester score. Duty et al (2003aDuty et al ( , 2003bDuty et al ( , 2004Duty et al ( , 2005 and Hauser et al (2006) conducted a series of studies in male partners of subfertile couples recruited at an infertility clinic (US). They estimated associations between blood and urinary biomarkers of exposure to phthalates and various measures of semen quality and morphology.…”