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Nathaniel Rothman - One of the best experts on this subject based on the ideXlab platform.
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prediagnostic serum organochlorine insecticide concentrations and primary liver cancer a case control study nested within two prospective cohorts
International Journal of Cancer, 2019Co-Authors: Lawrence S Engel, Nathaniel Rothman, Emily C Zabor, Jaya M Satagopan, Anders Widell, Thomas R Obrien, Mingdong Zhang, Stephen K Van Den Eeden, Tom Kristian GrimsrudAbstract:Although experimental evidence indicates that certain organochlorine insecticides are hepatocarcinogens, epidemiologic evidence for most of these chemicals is very limited. We estimated associations, using prospectively collected sera, between organochlorine insecticide concentrations and cancer registry-identified primary liver cancer in two cohorts, one from the United States and one from Norway. In nested case–control studies, we used sera collected in the 1960s-1980s from 136 cases and 408 matched controls from the Kaiser Permanente Northern California Multiphasic Health Checkup (MHC) cohort and 84 cases and 252 matched controls from the population-based Norwegian Janus cohort. We measured concentrations of nine organochlorine insecticides/metabolites and markers of hepatitis B and C in sera. Adjusted odds ratios (OR) and 95% confidence intervals (CI) for tertiles of lipid-corrected organochlorines were calculated for each cohort using conditional logistic regression. Among MHC participants with sera from the 1960s, there was a suggestive exposure-response trend for trans-nonachlor (second and third tertile of analyte ORs = 1.63 and 1.95, respectively; p-trend = 0.08) and a nonsignificantly elevated risk for the highest tertile of Oxychlordane (OR = 1.87). Among Janus participants with sera from the 1970s, we observed an apparent trend for p,p’-DDT (second and third tertile ORs = 1.70 and 2.14, respectively; p-trend = 0.15). We observed little consistency in patterns of association between the cohorts. We found limited evidence that exposure to p,p’-DDT and chlordane-related Oxychlordane and trans-nonachlor may be associated with increased risk of primary liver cancer. However, the modest strength of these associations and their lack of concordance between cohorts necessitate caution in their interpretation. (Less)
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Research | Articles Risk of Non-Hodgkin’s Lymphoma and Prediagnostic Serum Organochlorines: β-Hexachlorocyclohexane, Chlordane/Heptachlor-Related
2013Co-Authors: Kenneth P Cantor, Larry L Needham, John W Brock, Kathy J Helzlsouer, Shelia Hoar Zahm, George W Comstock, Paul T. Strickl, David Bush, Nathaniel RothmanAbstract:Increases in non-Hodgkin’s lymphoma (NHL) incidence and mortality rates during the past few decades remain largely unexplained. Studies suggest that organochlorine pesticides may contribute to an increased risk of NHL. In 1974, serum samples were obtained from 25,802 participants in the Campaign Against Cancer and Stroke in Washington County, Maryland (USA), and cryopreserved for future study. We measured prediagnostic levels of chlordane, lindane (γ-hexachlorocyclohexane), β-hexachlorocyclohexane, transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane, dieldrin, and hexachlorobenzene in serum samples of 74 cases of NHL and 147 matched controls. Previously, we found an association between NHL and serum levels of total PCBs (polychlorinated biphenyls), but not DDT (dichlorodiphenyltrichloroethane) and related compounds. In this instance, there was no evidence of an association between NHL risk and serum levels of any of the individual lipid- and recovery-corrected organochlorines that we evaluated, nor of the summed chlordane-related compounds (transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane). These findings do not support the hypothesis that the organochlorine compounds included in this study are strongly linked to the development of NHL. The possibility of a weak association cannot be excluded by these data. Key words: chlordane, dieldrin, heptachlor, hexachlorobenzene, hexachlorocyclohexane, lindane, non-Hodgkin’s lymphoma, organochlorine. Environ Health Perspect 111:179–183 (2003). [Online 15 November 2002] doi:10.1289/ehp.4347 available vi
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risk of non hodgkin s lymphoma and prediagnostic serum organochlorines beta hexachlorocyclohexane chlordane heptachlor related compounds dieldrin and hexachlorobenzene
Environmental Health Perspectives, 2002Co-Authors: Kenneth P Cantor, Larry L Needham, Paul T Strickland, John W Brock, David E Bush, Kathy J Helzlsouer, Shelia Hoar Zahm, George W Comstock, Nathaniel RothmanAbstract:Increases in non-Hodgkin's lymphoma (NHL) incidence and mortality rates during the past few decades remain largely unexplained. Studies suggest that organochlorine pesticides may contribute to an increased risk of NHL. In 1974, serum samples were obtained from 25,802 participants in the Campaign Against Cancer and Stroke in Washington County, Maryland (USA), and cryopreserved for future study. We measured prediagnostic levels of chlordane, lindane (gamma-hexachlorocyclohexane), beta-hexachlorocyclohexane, transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane, dieldrin, and hexachlorobenzene in serum samples of 74 cases of NHL and 147 matched controls. Previously, we found an association between NHL and serum levels of total PCBs (polychlorinated biphenyls), but not DDT (dichlorodiphenyltrichloroethane) and related compounds. In this instance, there was no evidence of an association between NHL risk and serum levels of any of the individual lipid- and recovery-corrected organochlorines that we evaluated, nor of the summed chlordane-related compounds (transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane). These findings do not support the hypothesis that the organochlorine compounds included in this study are strongly linked to the development of NHL. The possibility of a weak association cannot be excluded by these data.
Hans Rudolf Buser - One of the best experts on this subject based on the ideXlab platform.
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enantioselective determination of various chlordane components and metabolites using high resolution gas chromatography with a β cyclodextrin derivative as chiral selector and electron capture negative ion mass spectrometry detection
Chemosphere, 1997Co-Authors: Markus D Muller, Hans Rudolf Buser, Christoffer RappeAbstract:Abstract Enantioenriched fractions of various chiral chlordane compounds (heptachlor, cis -chlordane, trans -chlordane) and metabolites ( cis - and trans-heptachlorepoxide, Oxychlordane) were used to evaluate a high-resolution gas chromatography (HRGC) column with heptakis-[2,3-dimethyl-6- t -butyldimethylsilyl]-β-cyclodextrin (TBDM) as chiral selector and enantiomer elution sequences were determined. The enantioenriched fractions were previously isolated from the racemates by enantioselective high-performance liquid chromatography (HPLC) using a permethylated β-cyclo-odextrin. Additionally, two octachlordanes, U82 and MC5, were isolated as racemates from technical chlordane using HRGC and then used for reference purposes. The TBDM column enantiomerically resolved cis - and trans-chlordane, MC5, cis - and trans-heptachlorepoxide, and Oxychlordane; it did not enantiomerically resolve heptachlor, the octachlordane U82 and the nonachlordane MC6. A 12-m column resulted in a better enantiomer resolution than a longer (23-m) column of the same type due to a lower elution temperature. The TBDM column was used to analyze technical chlordane and chlordane residues in the fish oil reference material SRM 1588, a cod liver oil. Isomer and enantiomer ratios of chlordane residues in this reference material are reported and compared to those reported in earlier studies on the same material and to data on other fish species from the Baltic.
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identification of the and enantiomers of chiral chlordane compounds using chiral high performance liquid chromatography chiroptical detection and chiral high resolution gas chromatography mass spectrometry
Analytical Chemistry, 1994Co-Authors: Markus D. Mueller, Hans Rudolf BuserAbstract:Synthetic racemic (±)-cis-chlordane, (±)-trans-chlordane, (±)-chlordene, (±)-heptachlor, (±)-heptachorepoxide, and (±)-Oxychlordane were analyzed by chiral high-performance liquid chromatography (HPLC) using refractive index (RI) and chiroptical detection. Chiroptical detection allowed the assignment of the (+)- and (-)-enantiomers of all compounds although some were almost unresolved and showed no apparent enantiomer resolution by other detection means (RI)
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Enantioselective determination of chlordane components, metabolites, and photoconversion products in environmental samples using chiral high-resolution gas chromatography and mass spectrometry
Environmental Science & Technology, 1993Co-Authors: Hans Rudolf Buser, Markus D. MuellerAbstract:Enantiomer separation of various chlordane compounds, including heptachlor, the oxygenated metabolites heptachlor epoxide (HEP) and Oxychlordane (OXY), and photoconversion products was investigated using chiral high-resolution gas chromatography and detection by electron ionization (EI) and electron-capture, negative ionization (ECNI) mass spectrometry (MS). In technical chlordane and in ambient air from Scandinavia, heptachlor and the chiral octa- and nonachlordanes were present in enantiomeric ratios of 1:1. The results indicate input of these compounds via aerial transport into the northern environment as racemic mixtures. Laboratory experiments using solid-phase photolysis by natural sunlight yielded caged and half-caged products from heptachlor and cis-chlordane, respectively.
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Enantiomer separation of chlordane components and metabolites using chiral high-resolution gas chromatography and detection by mass spectrometric techniques
Analytical Chemistry, 1992Co-Authors: Hans Rudolf Buser, Markus D. MuellerAbstract:Octa- and nonachlordanes, Oxychlordane, and heptachlor exo- and endo-epoxide were analyzed using achiral and chiral high-resolution gas chromatography (HRGC) and detection by electron ionization (EI) and electron-capture, negative ionization mass spectrometry (ECNI MS). Two β-cyclodextrin (β-CD) derivatives were used as chiral selectors and dissolved in a polysiloxane stationary phase (PS086)
Shelia Hoar Zahm - One of the best experts on this subject based on the ideXlab platform.
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serum concentrations of dde pcbs and other persistent organic pollutants and mammographic breast density in triana alabama a highly exposed population
Environmental Research, 2020Co-Authors: Jennifer Rusiecki, Shelia Hoar Zahm, H Denicroberts, Celia Byrne, J Cash, C Raines, Louise A Brinton, Thomas J Mason, Matthew R Bonner, A BlairAbstract:Abstract Introduction Although some persistent organic pollutants (POPs) are considered human carcinogens, results from studies evaluating exposures and breast cancer risk have been inconsistent, potentially related to varying ages at exposure. Additionally, few studies evaluated the association between POPs exposure and mammographic breast density (MBD), an intermediate biomarker of breast cancer risk. We carried out a cross-sectional study to investigate associations between serum POPs concentrations and MBD measured in 1998 in female residents of Triana, Alabama, in a predominately African American population with high POPs exposures, particularly to p,p'-DDT (1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane). Methods We measured lipid-adjusted serum concentrations (ng/g lipid) of p,p'-DDT and its main metabolite p,p'-DDE (1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene), polychlorinated biphenyls (PCBs), β-hexachlorocyclohexane (β-HCCH), heptachlor epoxide, Oxychlordane, trans-nonachlor, mirex, and aldrin for each woman in our study (n = 210). We also measured two MBD metrics, percent MBD (%MBD) and area of MBD (aMBD). Using adjusted Spearman correlation coefficients (rs) we evaluated correlations between %MBD and aMBD with individual POPs in the overall population and by age group (19–40, 41–54, and 55–91 years) and also estimated adjusted mean measures of MBD with 95% confidence intervals across tertiles of analytes using generalized linear models (GLM). We calculated p-values for multiplicative interaction by age group using GLM. Additional analyses excluded women with current hormone replacement therapy (HRT) use and evaluated early-life exposure (prior to age 18) during the heaviest contamination period in Triana (1947–90). Results Among all women, we found no correlation between p,p’-DDE and %MBD, but after age stratification and exclusion of HRT users, there was a suggestion of a difference by age group, with younger women having a weak positive correlation (rs = 0.12, p = 0.37) and older women having a weak negative correlation (rs = −0.12, p = 0.43); pinteraction = 0.06. In contrast, PCBs were weakly positively correlated with %MBD among all women, with the correlation magnitudes increasing after excluding current HRT users (rs-total PCBs = 0.17, p = 0.03). After age stratification and exclusion of HRT users, correlations for PCBs were higher among younger and middle-age women, with only a handful of these correlations being statistically significant. For β-HCCH, the strongest finding was a negative correlation among older women (rs = −0.26, p = 0.07). Correlations were positive predominantly in the younger age group for heptachlor epoxide (rs = 0.27, p = 0.04), Oxychlordane (rs = 0.35, p = 0.006), and trans-nonachlor (rs = 0.37, p = 0.003), and largely null for the middle and older age groups; pinteraction range: 0.03–0.05. Similar patterns were found in GLM analyses using tertiles of exposure and aMBD as the metric for MBD. Women exposed during the heaviest chemical contamination period in Triana prior to age 18 had positive correlations between %MBD and PCBs, heptachlor epoxide, mirex, Oxychlordane, and trans-nonachlor. Conclusions In this population, despite high exposures to p,p’-DDT and thus high serum concentrations of its main metabolite, p,p’-DDE, we did not find strong evidence of a positive association with MBD. In fact, there was some evidence of a negative association among older women for p,p’-DDE; a similar pattern was found for β-HCCH. However, younger women with higher serum levels of PCBs, heptachlor epoxide, Oxychlordane, and trans-nonachlor, who were likely exposed in early life, had higher MBD. These findings should be replicated in larger studies.
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Research | Articles Risk of Non-Hodgkin’s Lymphoma and Prediagnostic Serum Organochlorines: β-Hexachlorocyclohexane, Chlordane/Heptachlor-Related
2013Co-Authors: Kenneth P Cantor, Larry L Needham, John W Brock, Kathy J Helzlsouer, Shelia Hoar Zahm, George W Comstock, Paul T. Strickl, David Bush, Nathaniel RothmanAbstract:Increases in non-Hodgkin’s lymphoma (NHL) incidence and mortality rates during the past few decades remain largely unexplained. Studies suggest that organochlorine pesticides may contribute to an increased risk of NHL. In 1974, serum samples were obtained from 25,802 participants in the Campaign Against Cancer and Stroke in Washington County, Maryland (USA), and cryopreserved for future study. We measured prediagnostic levels of chlordane, lindane (γ-hexachlorocyclohexane), β-hexachlorocyclohexane, transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane, dieldrin, and hexachlorobenzene in serum samples of 74 cases of NHL and 147 matched controls. Previously, we found an association between NHL and serum levels of total PCBs (polychlorinated biphenyls), but not DDT (dichlorodiphenyltrichloroethane) and related compounds. In this instance, there was no evidence of an association between NHL risk and serum levels of any of the individual lipid- and recovery-corrected organochlorines that we evaluated, nor of the summed chlordane-related compounds (transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane). These findings do not support the hypothesis that the organochlorine compounds included in this study are strongly linked to the development of NHL. The possibility of a weak association cannot be excluded by these data. Key words: chlordane, dieldrin, heptachlor, hexachlorobenzene, hexachlorocyclohexane, lindane, non-Hodgkin’s lymphoma, organochlorine. Environ Health Perspect 111:179–183 (2003). [Online 15 November 2002] doi:10.1289/ehp.4347 available vi
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risk of non hodgkin s lymphoma and prediagnostic serum organochlorines beta hexachlorocyclohexane chlordane heptachlor related compounds dieldrin and hexachlorobenzene
Environmental Health Perspectives, 2002Co-Authors: Kenneth P Cantor, Larry L Needham, Paul T Strickland, John W Brock, David E Bush, Kathy J Helzlsouer, Shelia Hoar Zahm, George W Comstock, Nathaniel RothmanAbstract:Increases in non-Hodgkin's lymphoma (NHL) incidence and mortality rates during the past few decades remain largely unexplained. Studies suggest that organochlorine pesticides may contribute to an increased risk of NHL. In 1974, serum samples were obtained from 25,802 participants in the Campaign Against Cancer and Stroke in Washington County, Maryland (USA), and cryopreserved for future study. We measured prediagnostic levels of chlordane, lindane (gamma-hexachlorocyclohexane), beta-hexachlorocyclohexane, transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane, dieldrin, and hexachlorobenzene in serum samples of 74 cases of NHL and 147 matched controls. Previously, we found an association between NHL and serum levels of total PCBs (polychlorinated biphenyls), but not DDT (dichlorodiphenyltrichloroethane) and related compounds. In this instance, there was no evidence of an association between NHL risk and serum levels of any of the individual lipid- and recovery-corrected organochlorines that we evaluated, nor of the summed chlordane-related compounds (transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane). These findings do not support the hypothesis that the organochlorine compounds included in this study are strongly linked to the development of NHL. The possibility of a weak association cannot be excluded by these data.
John W Brock - One of the best experts on this subject based on the ideXlab platform.
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Research | Articles Risk of Non-Hodgkin’s Lymphoma and Prediagnostic Serum Organochlorines: β-Hexachlorocyclohexane, Chlordane/Heptachlor-Related
2013Co-Authors: Kenneth P Cantor, Larry L Needham, John W Brock, Kathy J Helzlsouer, Shelia Hoar Zahm, George W Comstock, Paul T. Strickl, David Bush, Nathaniel RothmanAbstract:Increases in non-Hodgkin’s lymphoma (NHL) incidence and mortality rates during the past few decades remain largely unexplained. Studies suggest that organochlorine pesticides may contribute to an increased risk of NHL. In 1974, serum samples were obtained from 25,802 participants in the Campaign Against Cancer and Stroke in Washington County, Maryland (USA), and cryopreserved for future study. We measured prediagnostic levels of chlordane, lindane (γ-hexachlorocyclohexane), β-hexachlorocyclohexane, transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane, dieldrin, and hexachlorobenzene in serum samples of 74 cases of NHL and 147 matched controls. Previously, we found an association between NHL and serum levels of total PCBs (polychlorinated biphenyls), but not DDT (dichlorodiphenyltrichloroethane) and related compounds. In this instance, there was no evidence of an association between NHL risk and serum levels of any of the individual lipid- and recovery-corrected organochlorines that we evaluated, nor of the summed chlordane-related compounds (transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane). These findings do not support the hypothesis that the organochlorine compounds included in this study are strongly linked to the development of NHL. The possibility of a weak association cannot be excluded by these data. Key words: chlordane, dieldrin, heptachlor, hexachlorobenzene, hexachlorocyclohexane, lindane, non-Hodgkin’s lymphoma, organochlorine. Environ Health Perspect 111:179–183 (2003). [Online 15 November 2002] doi:10.1289/ehp.4347 available vi
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maternal pregnancy levels of trans nonachlor and Oxychlordane and prevalence of cryptorchidism and hypospadias in boys
Environmental Health Perspectives, 2011Co-Authors: Britton Trabert, John W Brock, Matthew P Longnecker, Mark A Klebanoff, Katherine A McglynnAbstract:Background: The etiologies of the male urogenital anomalies—cryptorchidism and hypospadias—are poorly understood. Given positive associations between chlordane isomers and testicular germ cell tumors, it is reasonable to assume that chlordanes might also be associated with other testicular dysgenesis syndrome disorders, namely cryptorchidism and hypospadias. Objective: To examine whether exposure to in utero chlordane is related to cryptorchidism and hypospadias, we evaluated levels of chlordane derivatives, trans-nonachlor and Oxychlordane, among pregnant women enrolled in the Collaborative Perinatal Project (CPP). Methods: From 1959 to 1965, the CPP enrolled pregnant women at 12 U.S. medical centers. We analyzed serum trans-nonachlor and Oxychlordane levels measured in third-trimester serum from the mothers of 217 sons with cryptorchidism, 197 sons with hypospadias, and 557 sons with neither condition. Adjusted odds ratios (ORs) and 95% confidence intervals were calculated using conditional logistic regression. Results: The quartile-specific ORs for cryptorchidism or hypospadias show no notable associations with trans-nonachlor or Oxychlordane. Further, there were no significant trends with increasing quartile of maternal trans-nonachlor or Oxychlordane level in either cryptorchidism or hypospadias (p-trend all > 0.45). Conclusions: The results do not support an association between chlordane levels and cryptorchidism or hypospadias. It is unlikely that current chlordane exposure is related to the development of either anomaly, given that serum chlordane levels at the time of sample collection, the early 1960s, were considerably higher than levels at present.
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risk of non hodgkin s lymphoma and prediagnostic serum organochlorines beta hexachlorocyclohexane chlordane heptachlor related compounds dieldrin and hexachlorobenzene
Environmental Health Perspectives, 2002Co-Authors: Kenneth P Cantor, Larry L Needham, Paul T Strickland, John W Brock, David E Bush, Kathy J Helzlsouer, Shelia Hoar Zahm, George W Comstock, Nathaniel RothmanAbstract:Increases in non-Hodgkin's lymphoma (NHL) incidence and mortality rates during the past few decades remain largely unexplained. Studies suggest that organochlorine pesticides may contribute to an increased risk of NHL. In 1974, serum samples were obtained from 25,802 participants in the Campaign Against Cancer and Stroke in Washington County, Maryland (USA), and cryopreserved for future study. We measured prediagnostic levels of chlordane, lindane (gamma-hexachlorocyclohexane), beta-hexachlorocyclohexane, transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane, dieldrin, and hexachlorobenzene in serum samples of 74 cases of NHL and 147 matched controls. Previously, we found an association between NHL and serum levels of total PCBs (polychlorinated biphenyls), but not DDT (dichlorodiphenyltrichloroethane) and related compounds. In this instance, there was no evidence of an association between NHL risk and serum levels of any of the individual lipid- and recovery-corrected organochlorines that we evaluated, nor of the summed chlordane-related compounds (transnonachlor, heptachlor, heptachlor epoxide, Oxychlordane). These findings do not support the hypothesis that the organochlorine compounds included in this study are strongly linked to the development of NHL. The possibility of a weak association cannot be excluded by these data.
Markus D. Mueller - One of the best experts on this subject based on the ideXlab platform.
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identification of the and enantiomers of chiral chlordane compounds using chiral high performance liquid chromatography chiroptical detection and chiral high resolution gas chromatography mass spectrometry
Analytical Chemistry, 1994Co-Authors: Markus D. Mueller, Hans Rudolf BuserAbstract:Synthetic racemic (±)-cis-chlordane, (±)-trans-chlordane, (±)-chlordene, (±)-heptachlor, (±)-heptachorepoxide, and (±)-Oxychlordane were analyzed by chiral high-performance liquid chromatography (HPLC) using refractive index (RI) and chiroptical detection. Chiroptical detection allowed the assignment of the (+)- and (-)-enantiomers of all compounds although some were almost unresolved and showed no apparent enantiomer resolution by other detection means (RI)
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Enantioselective determination of chlordane components, metabolites, and photoconversion products in environmental samples using chiral high-resolution gas chromatography and mass spectrometry
Environmental Science & Technology, 1993Co-Authors: Hans Rudolf Buser, Markus D. MuellerAbstract:Enantiomer separation of various chlordane compounds, including heptachlor, the oxygenated metabolites heptachlor epoxide (HEP) and Oxychlordane (OXY), and photoconversion products was investigated using chiral high-resolution gas chromatography and detection by electron ionization (EI) and electron-capture, negative ionization (ECNI) mass spectrometry (MS). In technical chlordane and in ambient air from Scandinavia, heptachlor and the chiral octa- and nonachlordanes were present in enantiomeric ratios of 1:1. The results indicate input of these compounds via aerial transport into the northern environment as racemic mixtures. Laboratory experiments using solid-phase photolysis by natural sunlight yielded caged and half-caged products from heptachlor and cis-chlordane, respectively.
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Enantiomer separation of chlordane components and metabolites using chiral high-resolution gas chromatography and detection by mass spectrometric techniques
Analytical Chemistry, 1992Co-Authors: Hans Rudolf Buser, Markus D. MuellerAbstract:Octa- and nonachlordanes, Oxychlordane, and heptachlor exo- and endo-epoxide were analyzed using achiral and chiral high-resolution gas chromatography (HRGC) and detection by electron ionization (EI) and electron-capture, negative ionization mass spectrometry (ECNI MS). Two β-cyclodextrin (β-CD) derivatives were used as chiral selectors and dissolved in a polysiloxane stationary phase (PS086)
