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Nathaniel Rothman - 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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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.
Kenneth P Cantor - 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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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.
Lucia Santos - One of the best experts on this subject based on the ideXlab platform.
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uncertainty associated to the analysis of organochlorine pesticides in water by solid phase microextraction gas chromatography electron capture detection evaluation using two different approaches
Analytica Chimica Acta, 2006Co-Authors: Nuno Ratola, Lucia Santos, Paulo Herbert, Arminda AlvesAbstract:Abstract As the performances of analytical instrumentation are being gradually enhanced, the limits of detection become increasingly lower, allowing more environmental contaminants to be determined in different matrices. Problems emerge when dealing with data from different origins, once the uncertainty of the results is difficult to be compared, especially if its calculation procedure is rather different, as very often happens. Samples of two organochlorine pesticides of somewhat opposite characteristics (lindane and Heptachlor, classified as persistent organic pollutants—POPs) were analyzed in aqueous media using headspace solid-phase microextraction (SPME) prior to gas chromatography–electron capture detection (GC–ECD) and this methodology was in-house validated. Detection limits of 0.097 and 0.050 μg l −1 , average intermediate precision of 11.6% and 27.5%, and average recovery of 95.6% and 103.0%, for lindane and Heptachlor, respectively, were found. In the absence of available interlaboratory studies to assess the reliability of the results, the expanded uncertainty was calculated following two different approaches ( bottom-up /Eurachem and modified top-down ) and the results were compared. Globally it was clearly shown that, for both pesticides, the lower the concentration range, the higher the uncertainty associated to the results. Expanded uncertainties estimated by bottom-up /Eurachem approach varied from 51% to 14% for a lindane concentration range of 0.1–1 μg l −1 , and from 48% to 24% for a Heptachlor range of 0.1–2 μg l −1 . Modified top-down approach pointed to 44% (lindane and Heptachlor) in the same ranges, meaning that a uniform procedure for uncertainty estimation should be adopted.
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development and validation of a novel method for the analysis of chlorinated pesticides in soils using microwave assisted extraction headspace solid phase microextraction and gas chromatography tandem mass spectrometry
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Paulo Herbert, Arminda Alves, Simone Morais, Paula Paiga, Lucia SantosAbstract:A new procedure for determining eleven organochlorine pesticides in soils using microwave-assisted extraction (MAE) and headspace solid phase microextraction (HS-SPME) is described. The studied pesticides consisted of mirex, alpha- and gamma-chlordane, p,p'-DDT, Heptachlor, Heptachlor epoxide isomer A, gamma-hexachlorocyclohexane, dieldrin, endrin, aldrine and hexachlorobenzene. The HS-SPME was optimized for the most important parameters such as extraction time, sample volume and temperature. The present analytical procedure requires a reduced volume of organic solvents and avoids the need for extract clean-up steps. For optimized conditions the limits of detection for the method ranged from 0.02 to 3.6 ng/g, intermediate precision ranged from 14 to 36% (as CV%), and the recovery from 8 up to 51%. The proposed methodology can be used in the rapid screening of soil for the presence of the selected pesticides, and was applied to landfill soil samples.
Gan Zhang - One of the best experts on this subject based on the ideXlab platform.
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human health risk assessment congener specific analysis and spatial distribution pattern of organochlorine pesticides ocps through rice crop from selected districts of punjab province pakistan
Science of The Total Environment, 2015Co-Authors: Mehvish Mumtaz, Riffat Naseem Malik, Abdul Qadir, Adeel Mahmood, Andleeb Mehmood, Zubaida Yousaf, Nadia Jamil, Irfan Ahmed Shaikh, Habib Ali, Gan ZhangAbstract:Abstract To evaluate the screening level risk assessment of OCPs in rice ( Oryza sativa L.) straw (n = 20) and rice grains (n = 20), samples were collected from different districts of Punjab Province, Pakistan. ∑ OCPs' levels (ng g − 1 ) in rice straw and grains ranged from 3.63 to 39.40, 2.72 to 49.89, respectively. DDTs were found predominant over the other detected OCP isomers followed by HCH and Heptachlor. Results of one way ANOVA reflected no significant difference for OCPs' levels among sampling sites, except Heptachlor for rice grains. ∑ OCPs' concentration in rice straw samples was exceeding the minimal residual levels (MRLs) (Australian and Japanese). Results of dietary intake and risk assessment suggested that rice straw is not safe for animals to consume as fodder. Human health was suggested to have some carcinogenic risks by consumption of rice grains, however, no considerable hazardous risk (non-carcinogenic) to human health was found.
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assessing spatial distribution sources and human health risk of organochlorine pesticide residues in the soils of arid and semiarid areas of northwest china
Environmental Science and Pollution Research, 2014Co-Authors: Tao Huang, Hui Tian, Zhongyuan Ding, Gan Zhang, Jun LiAbstract:Thirty-two topsoil samples were collected to analyze the residue levels of organochlorine pesticides (OCPs) in topsoil of arid and semiarid areas of northwest China in 2011. Results showed that DDTs were the dominant contaminants with a mean concentration of 12.52 ng/g. The spatial distribution characteristics indicated that α-hexachlorocyclohexanes (HCHs) were mainly used in rural sites, whereas hexachlorobenzene (HCB) and endosulfan were detected mostly in urban areas. DDTs, Heptachlor, and chlordane were found almost equally in both urban and rural areas. Source identification revealed that the current levels of HCHs in soils were attributable to the residues from their historical use and fresh usage of lindane (γ-HCH). DDTs were mainly from historical use and fresh usage of dicofol, and HCB was emitted from the chemical industry. It was also found that the current soil levels of Heptachlor were mainly from its historical usage, endosulfan from fresh input, and chlordane from long-range atmospheric transport, respectively. The noncarcinogenic health risk assessment with a model was also conducted using USEPA standards for adults and children. Results indicated that health risk under nondietary exposure to OCPs decreased in the sequence of ΣDDT > ΣHCH > HCB > ΣHeptachlor > Σendosulfan > Σchlordane. According to the reference dose from the USEPA, the health risk under nondietary exposure to OCPs in the soil samples was at a relatively safe level.
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assessing spatial distribution sources and human health risk of organochlorine pesticide residues in the soils of arid and semiarid areas of northwest china
Environmental Science and Pollution Research, 2014Co-Authors: Tao Huang, Hui Tian, Zhongyuan Ding, Gan Zhang, Qiang Guo, Xiaoxuan Mao, Hong GaoAbstract:Thirty-two topsoil samples were collected to analyze the residue levels of organochlorine pesticides (OCPs) in topsoil of arid and semiarid areas of northwest China in 2011. Results showed that DDTs were the dominant contaminants with a mean concentration of 12.52 ng/g. The spatial distribution characteristics indicated that α-hexachlorocyclohexanes (HCHs) were mainly used in rural sites, whereas hexachlorobenzene (HCB) and endosulfan were detected mostly in urban areas. DDTs, Heptachlor, and chlordane were found almost equally in both urban and rural areas. Source identification revealed that the current levels of HCHs in soils were attributable to the residues from their historical use and fresh usage of lindane (γ-HCH). DDTs were mainly from historical use and fresh usage of dicofol, and HCB was emitted from the chemical industry. It was also found that the current soil levels of Heptachlor were mainly from its historical usage, endosulfan from fresh input, and chlordane from long-range atmospheric transport, respectively. The noncarcinogenic health risk assessment with a model was also conducted using USEPA standards for adults and children. Results indicated that health risk under nondietary exposure to OCPs decreased in the sequence of ΣDDT > ΣHCH > HCB > ΣHeptachlor > Σendosulfan > Σchlordane. According to the reference dose from the USEPA, the health risk under nondietary exposure to OCPs in the soil samples was at a relatively safe level.
Arminda Alves - One of the best experts on this subject based on the ideXlab platform.
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uncertainty associated to the analysis of organochlorine pesticides in water by solid phase microextraction gas chromatography electron capture detection evaluation using two different approaches
Analytica Chimica Acta, 2006Co-Authors: Nuno Ratola, Lucia Santos, Paulo Herbert, Arminda AlvesAbstract:Abstract As the performances of analytical instrumentation are being gradually enhanced, the limits of detection become increasingly lower, allowing more environmental contaminants to be determined in different matrices. Problems emerge when dealing with data from different origins, once the uncertainty of the results is difficult to be compared, especially if its calculation procedure is rather different, as very often happens. Samples of two organochlorine pesticides of somewhat opposite characteristics (lindane and Heptachlor, classified as persistent organic pollutants—POPs) were analyzed in aqueous media using headspace solid-phase microextraction (SPME) prior to gas chromatography–electron capture detection (GC–ECD) and this methodology was in-house validated. Detection limits of 0.097 and 0.050 μg l −1 , average intermediate precision of 11.6% and 27.5%, and average recovery of 95.6% and 103.0%, for lindane and Heptachlor, respectively, were found. In the absence of available interlaboratory studies to assess the reliability of the results, the expanded uncertainty was calculated following two different approaches ( bottom-up /Eurachem and modified top-down ) and the results were compared. Globally it was clearly shown that, for both pesticides, the lower the concentration range, the higher the uncertainty associated to the results. Expanded uncertainties estimated by bottom-up /Eurachem approach varied from 51% to 14% for a lindane concentration range of 0.1–1 μg l −1 , and from 48% to 24% for a Heptachlor range of 0.1–2 μg l −1 . Modified top-down approach pointed to 44% (lindane and Heptachlor) in the same ranges, meaning that a uniform procedure for uncertainty estimation should be adopted.
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development and validation of a novel method for the analysis of chlorinated pesticides in soils using microwave assisted extraction headspace solid phase microextraction and gas chromatography tandem mass spectrometry
Analytical and Bioanalytical Chemistry, 2006Co-Authors: Paulo Herbert, Arminda Alves, Simone Morais, Paula Paiga, Lucia SantosAbstract:A new procedure for determining eleven organochlorine pesticides in soils using microwave-assisted extraction (MAE) and headspace solid phase microextraction (HS-SPME) is described. The studied pesticides consisted of mirex, alpha- and gamma-chlordane, p,p'-DDT, Heptachlor, Heptachlor epoxide isomer A, gamma-hexachlorocyclohexane, dieldrin, endrin, aldrine and hexachlorobenzene. The HS-SPME was optimized for the most important parameters such as extraction time, sample volume and temperature. The present analytical procedure requires a reduced volume of organic solvents and avoids the need for extract clean-up steps. For optimized conditions the limits of detection for the method ranged from 0.02 to 3.6 ng/g, intermediate precision ranged from 14 to 36% (as CV%), and the recovery from 8 up to 51%. The proposed methodology can be used in the rapid screening of soil for the presence of the selected pesticides, and was applied to landfill soil samples.