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Russ Hauser - One of the best experts on this subject based on the ideXlab platform.

  • dna damage in human sperm is related to urinary levels of phthalate monoester and oxidative metabolites
    Human Reproduction, 2007
    Co-Authors: Russ Hauser, Narendra P Singh, Susan M Duty, Manori J Silva, Louise Ryan, John D Meeker, Antonia M Calafat
    Abstract:

    BACKGROUND: The ubiquitous use of phthalate esters in plastics, personal care products and food packaging materials results in widespread general population exposure. In this report, we extend our preliminary study on the relationship between urinary concentrations of phthalate metabolites and sperm DNA damage among a larger sample of men and include measurements of mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), two oxidative metabolites of di-(2-ethylhexyl) phthalate (DEHP). METHODS: Among 379 men from an infertility clinic, urinary concentrations of phthalate metabolites were measured using isotope-dilution highperformance liquid chromatography–tandem mass spectrometry. Sperm DNA damage measurements, assessed with the neutral comet assay, included comet extent (CE), percentage of DNA in tail (Tail%) and tail Distributed Moment (TDM). RESULTS: Monoethyl phthalate (MEP), a metabolite of diethyl phthalate, was associated with increased DNA damage, confirming our previous findings. Mono-(2-ethylhexyl) phthalate (MEHP), a metabolite of DEHP, was associated with DNA damage after adjustment for the oxidative DEHP metabolites. After adjustment for MEHHP, for an interquartile range increase in urinary MEHP, CE increased 17.3% [95% confidence interval (CI) = 8.7–25.7%], TDM increased 14.3% (95% CI = 6.8–21.7%) and Tail% increased 17.5% (95% CI = 3.5–31.5%). CONCLUSIONS: Sperm DNA damage was associated with MEP and with MEHP after adjusting for DEHP oxidative metabolites, which may serve as phenotypic markers of DEHP metabolism to ‘less toxic’ metabolites. The urinary levels of phthalate metabolites among these men were similar to those reported for the US general population, suggesting that exposure to some phthalates may affect the population distribution of sperm DNA damage.

  • relationship between human semen parameters and deoxyribonucleic acid damage assessed by the neutral comet assay
    Fertility and Sterility, 2004
    Co-Authors: Ana T Trisini, Narendra P Singh, Susan M Duty, Russ Hauser
    Abstract:

    Objective To explore the association between semen parameters and sperm DNA damage. Design Cross-sectional. Setting Andrology clinic. Patient(s) Two hundred fifty-seven men undergoing infertility assessment. Intervention(s) None. Main outcome measure(s) Sperm concentration and motility were measured using computer-assisted sperm analysis; morphology was scored using the strict criteria. The neutral comet assay was used to measure sperm DNA damage. Comet assay parameters included comet extent, percent DNA in the comet tail, and tail Distributed Moment, an integrated measure of length and intensity. We also scored cells that were too long to measure (>300 μm), which we referred to as cells with high DNA damage. Result(s) Men older than 35 years had a statistically significant increase in the number of cells with high DNA damage as compared with younger men. In age-adjusted regression analyses, the most consistent associations were found between semen parameters and the number of cells with high DNA damage. For an interquartile range change in the number of cells with high DNA damage, sperm concentration declined 14.2 × 10 6 /mL, motility declined 4.3%, and morphology declined 0.5%. Comet extent and percent DNA in the comet tail were also associated with a decline in sperm concentration and motility, respectively. Conclusion(s) Although there were associations between semen and comet assay parameters, their magnitudes were weak, suggesting that the comet assay provides additional independent information on sperm function.

  • lack of an association between environmental exposure to polychlorinated biphenyls and p p dde and dna damage in human sperm measured using the neutral comet assay
    Human Reproduction, 2003
    Co-Authors: Russ Hauser, Narendra P Singh, Zuying Chen, Lucille Pothier, Larisa M Altshul
    Abstract:

    BACKGROUND: Chlorinated organic chemicals, such as polychlorinated biphenyls (PCB), hexachlorobenzene (HCB), dichlorodiphenyl trichloroethane (DDT), and dichlorodiphenyl dichloroethene (DDE, the most stable daughter compound of DDT) are persistent lipophilic compounds found in a large portion of the general population. To explore the hypothesis that environmental exposure to these compounds is associated with altered DNA integrity in human sperm, a study of 212 male partners of a sub-fertile couple who presented to the Massachusetts General Hospital Andrology Laboratory was conducted. METHODS: The neutral single cell microgel electrophoresis assay (comet assay) was used to assess DNA integrity in sperm. VisComet image analysis software was used to measure total comet length, the proportion of DNA present in the comet tail, and tail Distributed Moment, an integrated measure of length and intensity. RESULTS: In the regression analyses, there were no statistically significant consistent associations between the comet assay parameters and any of the individual PCB congeners, sum of PCB, or p,p¢-DDE. CONCLUSION: These results suggest that there are not strong relationships between adult levels of these chlorinated organic compounds and sperm DNA damage as measured by the comet assay.

  • the relationship between environmental exposures to phthalates and dna damage in human sperm using the neutral comet assay
    Environmental Health Perspectives, 2002
    Co-Authors: Susan M Duty, Narendra P Singh, Manori J Silva, Dana B Barr, John W Brock, Louise Ryan, Robert F Herrick, David C Christiani, Russ Hauser
    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.

Susan M Duty - One of the best experts on this subject based on the ideXlab platform.

  • dna damage in human sperm is related to urinary levels of phthalate monoester and oxidative metabolites
    Human Reproduction, 2007
    Co-Authors: Russ Hauser, Narendra P Singh, Susan M Duty, Manori J Silva, Louise Ryan, John D Meeker, Antonia M Calafat
    Abstract:

    BACKGROUND: The ubiquitous use of phthalate esters in plastics, personal care products and food packaging materials results in widespread general population exposure. In this report, we extend our preliminary study on the relationship between urinary concentrations of phthalate metabolites and sperm DNA damage among a larger sample of men and include measurements of mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), two oxidative metabolites of di-(2-ethylhexyl) phthalate (DEHP). METHODS: Among 379 men from an infertility clinic, urinary concentrations of phthalate metabolites were measured using isotope-dilution highperformance liquid chromatography–tandem mass spectrometry. Sperm DNA damage measurements, assessed with the neutral comet assay, included comet extent (CE), percentage of DNA in tail (Tail%) and tail Distributed Moment (TDM). RESULTS: Monoethyl phthalate (MEP), a metabolite of diethyl phthalate, was associated with increased DNA damage, confirming our previous findings. Mono-(2-ethylhexyl) phthalate (MEHP), a metabolite of DEHP, was associated with DNA damage after adjustment for the oxidative DEHP metabolites. After adjustment for MEHHP, for an interquartile range increase in urinary MEHP, CE increased 17.3% [95% confidence interval (CI) = 8.7–25.7%], TDM increased 14.3% (95% CI = 6.8–21.7%) and Tail% increased 17.5% (95% CI = 3.5–31.5%). CONCLUSIONS: Sperm DNA damage was associated with MEP and with MEHP after adjusting for DEHP oxidative metabolites, which may serve as phenotypic markers of DEHP metabolism to ‘less toxic’ metabolites. The urinary levels of phthalate metabolites among these men were similar to those reported for the US general population, suggesting that exposure to some phthalates may affect the population distribution of sperm DNA damage.

  • relationship between human semen parameters and deoxyribonucleic acid damage assessed by the neutral comet assay
    Fertility and Sterility, 2004
    Co-Authors: Ana T Trisini, Narendra P Singh, Susan M Duty, Russ Hauser
    Abstract:

    Objective To explore the association between semen parameters and sperm DNA damage. Design Cross-sectional. Setting Andrology clinic. Patient(s) Two hundred fifty-seven men undergoing infertility assessment. Intervention(s) None. Main outcome measure(s) Sperm concentration and motility were measured using computer-assisted sperm analysis; morphology was scored using the strict criteria. The neutral comet assay was used to measure sperm DNA damage. Comet assay parameters included comet extent, percent DNA in the comet tail, and tail Distributed Moment, an integrated measure of length and intensity. We also scored cells that were too long to measure (>300 μm), which we referred to as cells with high DNA damage. Result(s) Men older than 35 years had a statistically significant increase in the number of cells with high DNA damage as compared with younger men. In age-adjusted regression analyses, the most consistent associations were found between semen parameters and the number of cells with high DNA damage. For an interquartile range change in the number of cells with high DNA damage, sperm concentration declined 14.2 × 10 6 /mL, motility declined 4.3%, and morphology declined 0.5%. Comet extent and percent DNA in the comet tail were also associated with a decline in sperm concentration and motility, respectively. Conclusion(s) Although there were associations between semen and comet assay parameters, their magnitudes were weak, suggesting that the comet assay provides additional independent information on sperm function.

  • the relationship between environmental exposures to phthalates and dna damage in human sperm using the neutral comet assay
    Environmental Health Perspectives, 2002
    Co-Authors: Susan M Duty, Narendra P Singh, Manori J Silva, Dana B Barr, John W Brock, Louise Ryan, Robert F Herrick, David C Christiani, Russ Hauser
    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.

Narendra P Singh - One of the best experts on this subject based on the ideXlab platform.

  • dna damage in human sperm is related to urinary levels of phthalate monoester and oxidative metabolites
    Human Reproduction, 2007
    Co-Authors: Russ Hauser, Narendra P Singh, Susan M Duty, Manori J Silva, Louise Ryan, John D Meeker, Antonia M Calafat
    Abstract:

    BACKGROUND: The ubiquitous use of phthalate esters in plastics, personal care products and food packaging materials results in widespread general population exposure. In this report, we extend our preliminary study on the relationship between urinary concentrations of phthalate metabolites and sperm DNA damage among a larger sample of men and include measurements of mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), two oxidative metabolites of di-(2-ethylhexyl) phthalate (DEHP). METHODS: Among 379 men from an infertility clinic, urinary concentrations of phthalate metabolites were measured using isotope-dilution highperformance liquid chromatography–tandem mass spectrometry. Sperm DNA damage measurements, assessed with the neutral comet assay, included comet extent (CE), percentage of DNA in tail (Tail%) and tail Distributed Moment (TDM). RESULTS: Monoethyl phthalate (MEP), a metabolite of diethyl phthalate, was associated with increased DNA damage, confirming our previous findings. Mono-(2-ethylhexyl) phthalate (MEHP), a metabolite of DEHP, was associated with DNA damage after adjustment for the oxidative DEHP metabolites. After adjustment for MEHHP, for an interquartile range increase in urinary MEHP, CE increased 17.3% [95% confidence interval (CI) = 8.7–25.7%], TDM increased 14.3% (95% CI = 6.8–21.7%) and Tail% increased 17.5% (95% CI = 3.5–31.5%). CONCLUSIONS: Sperm DNA damage was associated with MEP and with MEHP after adjusting for DEHP oxidative metabolites, which may serve as phenotypic markers of DEHP metabolism to ‘less toxic’ metabolites. The urinary levels of phthalate metabolites among these men were similar to those reported for the US general population, suggesting that exposure to some phthalates may affect the population distribution of sperm DNA damage.

  • relationship between human semen parameters and deoxyribonucleic acid damage assessed by the neutral comet assay
    Fertility and Sterility, 2004
    Co-Authors: Ana T Trisini, Narendra P Singh, Susan M Duty, Russ Hauser
    Abstract:

    Objective To explore the association between semen parameters and sperm DNA damage. Design Cross-sectional. Setting Andrology clinic. Patient(s) Two hundred fifty-seven men undergoing infertility assessment. Intervention(s) None. Main outcome measure(s) Sperm concentration and motility were measured using computer-assisted sperm analysis; morphology was scored using the strict criteria. The neutral comet assay was used to measure sperm DNA damage. Comet assay parameters included comet extent, percent DNA in the comet tail, and tail Distributed Moment, an integrated measure of length and intensity. We also scored cells that were too long to measure (>300 μm), which we referred to as cells with high DNA damage. Result(s) Men older than 35 years had a statistically significant increase in the number of cells with high DNA damage as compared with younger men. In age-adjusted regression analyses, the most consistent associations were found between semen parameters and the number of cells with high DNA damage. For an interquartile range change in the number of cells with high DNA damage, sperm concentration declined 14.2 × 10 6 /mL, motility declined 4.3%, and morphology declined 0.5%. Comet extent and percent DNA in the comet tail were also associated with a decline in sperm concentration and motility, respectively. Conclusion(s) Although there were associations between semen and comet assay parameters, their magnitudes were weak, suggesting that the comet assay provides additional independent information on sperm function.

  • lack of an association between environmental exposure to polychlorinated biphenyls and p p dde and dna damage in human sperm measured using the neutral comet assay
    Human Reproduction, 2003
    Co-Authors: Russ Hauser, Narendra P Singh, Zuying Chen, Lucille Pothier, Larisa M Altshul
    Abstract:

    BACKGROUND: Chlorinated organic chemicals, such as polychlorinated biphenyls (PCB), hexachlorobenzene (HCB), dichlorodiphenyl trichloroethane (DDT), and dichlorodiphenyl dichloroethene (DDE, the most stable daughter compound of DDT) are persistent lipophilic compounds found in a large portion of the general population. To explore the hypothesis that environmental exposure to these compounds is associated with altered DNA integrity in human sperm, a study of 212 male partners of a sub-fertile couple who presented to the Massachusetts General Hospital Andrology Laboratory was conducted. METHODS: The neutral single cell microgel electrophoresis assay (comet assay) was used to assess DNA integrity in sperm. VisComet image analysis software was used to measure total comet length, the proportion of DNA present in the comet tail, and tail Distributed Moment, an integrated measure of length and intensity. RESULTS: In the regression analyses, there were no statistically significant consistent associations between the comet assay parameters and any of the individual PCB congeners, sum of PCB, or p,p¢-DDE. CONCLUSION: These results suggest that there are not strong relationships between adult levels of these chlorinated organic compounds and sperm DNA damage as measured by the comet assay.

  • the relationship between environmental exposures to phthalates and dna damage in human sperm using the neutral comet assay
    Environmental Health Perspectives, 2002
    Co-Authors: Susan M Duty, Narendra P Singh, Manori J Silva, Dana B Barr, John W Brock, Louise Ryan, Robert F Herrick, David C Christiani, Russ Hauser
    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.

Louise Ryan - One of the best experts on this subject based on the ideXlab platform.

  • dna damage in human sperm is related to urinary levels of phthalate monoester and oxidative metabolites
    Human Reproduction, 2007
    Co-Authors: Russ Hauser, Narendra P Singh, Susan M Duty, Manori J Silva, Louise Ryan, John D Meeker, Antonia M Calafat
    Abstract:

    BACKGROUND: The ubiquitous use of phthalate esters in plastics, personal care products and food packaging materials results in widespread general population exposure. In this report, we extend our preliminary study on the relationship between urinary concentrations of phthalate metabolites and sperm DNA damage among a larger sample of men and include measurements of mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), two oxidative metabolites of di-(2-ethylhexyl) phthalate (DEHP). METHODS: Among 379 men from an infertility clinic, urinary concentrations of phthalate metabolites were measured using isotope-dilution highperformance liquid chromatography–tandem mass spectrometry. Sperm DNA damage measurements, assessed with the neutral comet assay, included comet extent (CE), percentage of DNA in tail (Tail%) and tail Distributed Moment (TDM). RESULTS: Monoethyl phthalate (MEP), a metabolite of diethyl phthalate, was associated with increased DNA damage, confirming our previous findings. Mono-(2-ethylhexyl) phthalate (MEHP), a metabolite of DEHP, was associated with DNA damage after adjustment for the oxidative DEHP metabolites. After adjustment for MEHHP, for an interquartile range increase in urinary MEHP, CE increased 17.3% [95% confidence interval (CI) = 8.7–25.7%], TDM increased 14.3% (95% CI = 6.8–21.7%) and Tail% increased 17.5% (95% CI = 3.5–31.5%). CONCLUSIONS: Sperm DNA damage was associated with MEP and with MEHP after adjusting for DEHP oxidative metabolites, which may serve as phenotypic markers of DEHP metabolism to ‘less toxic’ metabolites. The urinary levels of phthalate metabolites among these men were similar to those reported for the US general population, suggesting that exposure to some phthalates may affect the population distribution of sperm DNA damage.

  • the relationship between environmental exposures to phthalates and dna damage in human sperm using the neutral comet assay
    Environmental Health Perspectives, 2002
    Co-Authors: Susan M Duty, Narendra P Singh, Manori J Silva, Dana B Barr, John W Brock, Louise Ryan, Robert F Herrick, David C Christiani, Russ Hauser
    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.

Manori J Silva - One of the best experts on this subject based on the ideXlab platform.

  • dna damage in human sperm is related to urinary levels of phthalate monoester and oxidative metabolites
    Human Reproduction, 2007
    Co-Authors: Russ Hauser, Narendra P Singh, Susan M Duty, Manori J Silva, Louise Ryan, John D Meeker, Antonia M Calafat
    Abstract:

    BACKGROUND: The ubiquitous use of phthalate esters in plastics, personal care products and food packaging materials results in widespread general population exposure. In this report, we extend our preliminary study on the relationship between urinary concentrations of phthalate metabolites and sperm DNA damage among a larger sample of men and include measurements of mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP) and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), two oxidative metabolites of di-(2-ethylhexyl) phthalate (DEHP). METHODS: Among 379 men from an infertility clinic, urinary concentrations of phthalate metabolites were measured using isotope-dilution highperformance liquid chromatography–tandem mass spectrometry. Sperm DNA damage measurements, assessed with the neutral comet assay, included comet extent (CE), percentage of DNA in tail (Tail%) and tail Distributed Moment (TDM). RESULTS: Monoethyl phthalate (MEP), a metabolite of diethyl phthalate, was associated with increased DNA damage, confirming our previous findings. Mono-(2-ethylhexyl) phthalate (MEHP), a metabolite of DEHP, was associated with DNA damage after adjustment for the oxidative DEHP metabolites. After adjustment for MEHHP, for an interquartile range increase in urinary MEHP, CE increased 17.3% [95% confidence interval (CI) = 8.7–25.7%], TDM increased 14.3% (95% CI = 6.8–21.7%) and Tail% increased 17.5% (95% CI = 3.5–31.5%). CONCLUSIONS: Sperm DNA damage was associated with MEP and with MEHP after adjusting for DEHP oxidative metabolites, which may serve as phenotypic markers of DEHP metabolism to ‘less toxic’ metabolites. The urinary levels of phthalate metabolites among these men were similar to those reported for the US general population, suggesting that exposure to some phthalates may affect the population distribution of sperm DNA damage.

  • the relationship between environmental exposures to phthalates and dna damage in human sperm using the neutral comet assay
    Environmental Health Perspectives, 2002
    Co-Authors: Susan M Duty, Narendra P Singh, Manori J Silva, Dana B Barr, John W Brock, Louise Ryan, Robert F Herrick, David C Christiani, Russ Hauser
    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.